Patent Publication Number: US-7909872-B2

Title: Minimally invasive apparatus to manipulate and revitalize spinal column disc

Description:
This is a continuation-in-part of U.S. patent application Ser. No. 11/638,652, filed Dec. 12, 2006, now U.S. Pat. No. 7,883,542, which is a continuation-in-part of U.S. patent application Ser. No. 11/472,060, filed Jun. 21, 2006, now U.S. Pat. No. 7,879,099, which is a continuation-in-part of U.S. patent application Ser. No. 11/404,938 filed Apr. 14, 2006, now U.S. Pat. No. 7,727,279, which is a continuation-in-part of U.S. patent application Ser. No. 11/351,665, filed Feb. 10, 2006, now abandoned, which is a continuation-in-part both of U.S. patent application Ser. No. 11/299,395, filed Dec. 12, 2005, now abandoned, and of U.S. patent application Ser. No. 11/241,143 filed Sep. 30, 2005, now abandoned, which application Ser. No. 11/241,143 filed Sep. 30, 2005 is a continuation-in-part of U.S. patent application Ser. No. 11/145,372, filed Jun. 3, 2005, now abandoned. 
    
    
     This invention pertains to spinal column discs. 
     More particularly, this invention pertains to an apparatus and method for manipulating and revitalizing a disc in a spinal column. 
     In a further respect, the invention pertains to a method to surgically revitalize a damaged disc in a spinal column without requiring that the vertebrae bounding the disc be spread apart or resected. 
     In another respect, the invention pertains to a method for revitalizing a disc by retaining substantially all of the existing disc structure and by manipulating the shape and dimension of the disc. 
     An intervertebral disc is a soft tissue compartment connecting the vertebra bones in a spinal column. Each healthy disc consists of two parts, an outer annulus fibrosis (hereinafter “the annulus”) and an inner nucleus pulposes (hereinafter “the nucleus”). The annulus completely circumscribes and encloses the nucleus. The annulus is connected to its adjacent associated pair of vertebrae by collagen fibers. 
     The intervertebral disc is an example of a soft tissue compartment adjoining first and second bones (vertebra) having an initial height and an initial width. Other joints consisting of a soft tissue compartment adjoining at least first and second bones having an initial height and an initial width include the joints of the hand, wrist, elbow, shoulder, foot, ankle, knee, hip, etc. 
     Typically, when a disc is damaged, the annulus ruptures and the nucleus herniates. Discectomy surgery removes the extruded nucleus, leaving behind the ruptured annulus. The ruptured annulus is, by itself, ineffective in controlling motion and supporting the loads applied by the adjacent pair of vertebrae. With time, the disc flattens, widens, and bulges, compressing nerves and producing pain. Uncontrolled loads are transmitted to each vertebra. Each vertebra tends to grow wider in an attempt to distribute and compensate for higher loads. When a vertebra grows, bone spurs form. The bone spurs further compress nerves, producing pain. 
     A variety of expandable intervertebral devices are disclosed in the art to replace the intervertebral disc. Such devices are implanted intermediate an adjacent pair of vertebra, and function to assist the vertebra. These devices do not assist the intervertebral disc. In fact, in many cases the disc is removed. 
     Prior art intervertebral devices are either static or dynamic. 
     A static intervertebral device eliminates motion. Static devices are generally square, rectangular, trapezoidal, or box shapes that are immobile. Static devices replace the disc to facilitate bone fusion. The insertion of a static device requires near total removal of the disc. An adjacent pair of vertebrae ordinarily are contoured to the static device and a bone graft. A static device temporarily maintains the vertebrae immobilized until the bone graft heals. Static devices may, on insertion, initially expand, but their final state is immobile. Core elements with the threads on one portion reversed or oppositely wound from threads on another portion have been frequently utilized to expand immobilization (fusion) devices. 
     Following are examples of static immobilization devices. 
     European Patent Application 0260044 provides “A spinal implant comprising an elongate body divided longitudinally into two portions and being insertable in the joint space between two adjacent vertebra, engageable contact surfaces between the body portions, and expansion means movable between the contact surfaces of the body portions for spacing body portions apart and adjusting the joint spacing between adjacent vertebrae.” The purpose of the spinal implant is “to provide a permanent implant to substitute a full bone graft in establishing distraction inter body fusion.” The intervertebral disc is eliminated and replaced by the implant. Motion is limited to one axis. “Preferably the cam means comprises two sleeves each locatable within its own enlarged cavity within the body and being screw-threadedly mounted on the rod. Rotation of the rod in one direction moves the cam means outwardly towards the ends of the body, whilst rotation in the opposite direction moves the cam means towards each other until the cam means meet centrally of the body. In the latter case the body will rock at its extreme ends thus ensuring subtleness between injured or diseased vertebrae.” The implant is cylindrical with at least one flat end limiting the insertion angle or direction. The device lacks an element or method to prevent disassembly upon traction or extension. “The exterior surface (of the implant) is of a porous material, smooth and coated with a bioactive material to chemically bond the bone and cartilage tissue of the vertebra to the implant.” 
     U.S. Pat. No. 5,658,335 to Allen provides “ . . . a spinal fixator with a convex housing which fits within the contours of the concave vertebral bodies, and is cupped by the bony edges of the bodies, enabling secure placement without the necessity for additional screws or plates.” The intervertebral disc is removed to insert the spinal fixator. When the fixator is being inserted, “ . . . teeth enter the vertebral body at an angle away from midline to prevent displacement of the fixator during spinal/flexure and/or extension.” In order to function properly, the fixator is highly dependent upon divergent teeth. One potential problem with the Allen fixator is that it can disengage from vertebrae when the spine is subjected to traction or tension. The Allen fixator can include external threads on the core member that are separated into two, oppositely wound portions, and can include a core member that defines an aperture for insertion of a tool to rotate the core member. 
     U.S. Patent Application 2004/017234A1 describes apparatus that engages apophyseal rings of an opposing pair of vertebrae when lateral members in the apparatus are in an extended configuration. The apparatus includes an expansion mechanism having a shaft. The shaft has threaded portions on opposite edges that threadly engage the lateral members. The threaded portions are oppositely threaded and have equal thread pitch. 
     U.S. Pat. No. 6,176,882 to Biederman et al. discloses a fusion device that is immobile after it is expanded. The shape of each of the side walls of the device is substantially trapezoidal to provide a truncated wedge-shaped body. The device includes a threaded spindle having two ends and two portions with opposite thread pitch. The adjusting element of the device comprises two wedge members. The teeth on the device are inwardly and outwardly adjustable so they can be individually adjusted to the prevailing anatomic shape of the end plates of each vertebra. Each portion of the spindle has a different thread pitch. 
     U.S. Pat. No. 5,514,180 to Heggeness, et al. discloses prosthetic devices that conform to the vertebral bone after removing the intervertebral disc or resecting the vertebra to conform to the device. The device is not expandable. 
     U.S. Patent Application No. 2005/0065610 discloses apparatus that engages and contacts each adjacent vertebra to stabilize the vertebra without the disc. The apparatus has sharp hard edges and is inserted into the disc space. 
     Dynamic devices move. Inserting a dynamic device like a total disc prosthesis requires a near total removal of disc tissue. A dynamic device ordinarily is inserted to contour to the vertebral bones without a bone graft. Usually the vertebral bones are contoured to the dynamic device. Round, curved, or circular shaped devices inserted after removing disc tissue or vertebral bone tend to migrate in the intervertebral disc space or subside within the vertebral bone. Dynamic devices are permanent devices that replace a disc, connect vertebral bones together, and allow movement. Dynamic devices initially may expand. Their final state is mobile. 
     Other dynamic devices require a partial removal of disc tissue. The devices are inserted within the interior (nucleus) of an intervertebral disc and contour to the vertebral bones. Nucleus devices are generally smaller than devices used as a total disc prosthesis. Nucleus devices often are single parts lacking mechanisms. Fixation generally is not used and the device typically migrates within the disc space or subsides in vertebral bones. Other dynamic devices do not have solid bearing surface but comprise liquid or gas. 
     An example of a dynamic disc devices is described in U.S. Pat. No. 6,419,704 to Ferree. The Ferree patent discloses an expandable disc replacement composed of a fiber reinforced sealed body. 
     Other devices and methods function to patch or seal a disc without substantially supporting the vertebra. Inserting these devices requires the removal of disc tissue. These devices are added to the annulus. This widening of the annulus and the device increases the risk of contacting the nerves of the spinal column when the disc is compressed. Still other devices must form a physical barrier with the annulus in order to function. A barrier positioned within the annulus prevents the annulus from healing. Still other devices change the material property of the disc. 
     U.S. Pat. No. 6,805,695 to Keith et al, provides, “ . . . positioning the implant around annular tissue.” The device must directly contact the annulus for it to function. The device is not expandable and requires the use of thermal energy to heat and denature the annulus changing the material properties of the disc. 
     The existing intervertebral support devices focus on substantially replacing a damaged intervertebral disc. 
     The existing intervertebral devices widen the disc increasing the likelihood of contacting the nerves of the spinal column when compressed. 
     Inserting the existing intervertebral support devices require enlarging the pre-existing spaced apart configuration of the pair of vertebra damaging the disc. 
     None of the existing intervertebral support devices focus on manipulating to preserve a damaged intervertebral disc. 
     Accordingly, it would be highly desirable to provide an improved method and apparatus to revitalize a damaged intervertebral disc. 
     Therefore, it is a principal object of the invention to provide an improved method and apparatus to facilitate the recovery and proper functioning of a damaged intervertebral disc. 
     A further object of the invention is to provide an improved method for inserting an intervertebral device in a disc without requiring surgical separation of adjacent vertebra and with minimal damage to the disc and vertebra. 
     Another object of the invention is to align properly the spine and to facilitate proper functioning of the discs in the spine. 
     Still a further object of the invention is to provide an improved method and apparatus for penetrating hard and soft tissue while minimizing the risk of injury to the tissue. 
    
    
     
       These and other, further and more specific objects and advantages of the invention will be apparent from the following detailed description of the invention, taken in conjunction with the drawings, in which: 
         FIG. 1  is a perspective view illustrating an intervertebral device constructed in accordance with the principles of the invention; 
         FIG. 1A  is a perspective view of a tool that can be utilized in the practice of the invention; 
         FIG. 2  is a perspective-partial section view of the device of  FIG. 1  illustrating additional construction details thereof; 
         FIG. 3  is an exploded view of certain components of the device of  FIG. 1 : 
         FIG. 4  is a perspective view further illustrating the device of  FIG. 1 ; 
         FIG. 5  is a perspective view of the device of  FIG. 1  illustrating certain components in ghost outline; 
         FIG. 6  is a top view illustrating the insertion of the device of  FIG. 1  in an intervertebral disc adjacent the spinal column; 
         FIG. 7  is a side elevation view further illustrating the insertion of the device of  FIG. 1  in the spinal column; 
         FIG. 8  is a top view illustrating a damaged intervertebral disc with a portion thereof bulging and pressing against the spinal column; 
         FIG. 9  is a top view illustrating the disc of  FIG. 8  manipulated with a device constructed in accordance with the invention to alter the shape and dimension of the disc to revitalize the disc and take pressure off the spinal column; 
         FIG. 10  is a top view illustrating the disc of  FIG. 8  manipulated with an alternate device constructed in accordance with the invention to alter the shape and dimension of the disc to revitalize the disc and take pressure off the spinal column; 
         FIG. 11  is a top view illustrating the disc of  FIG. 8  manipulated in accordance with the invention to alter the shape of the disc from a normal “C-shape” to an oval shape; 
         FIG. 12  is a side elevation view illustrating a bulging disc intermediate a pair of vertebrae; 
         FIG. 13  is a side elevation view illustrating the disc and vertebrae of  FIG. 12  after internal traction; 
         FIG. 14  is a side elevation view illustrating a rubber band or string that has a bulge similar to the bulge formed in a intervertebral disc; 
         FIG. 15  is a side elevation view illustrating the rubber band of  FIG. 14  after it has been tensioned to remove the bulge; 
         FIG. 16  is a perspective view illustrating spring apparatus in accordance with an alternate embodiment of the invention; 
         FIG. 17  is a front elevation view illustrating the embodiment of the invention of  FIG. 16 ; 
         FIG. 18  is a perspective view illustrating an insertion member utilized to implant the spring apparatus of  FIG. 16  in a spinal disc; 
         FIG. 19  is a top view illustrating the insertion member of  FIG. 18  after the spring apparatus is implant in a spinal disc; 
         FIG. 20  is a top view of a portion of a spinal column illustrating the spring of  FIG. 16  inserted in a disc; 
         FIG. 21  is a perspective view illustrating a spring apparatus constructed in accordance with a further embodiment of the invention; 
         FIG. 22  is a perspective view illustrating a spring apparatus constructed in accordance with another embodiment of the invention; 
         FIG. 23  is a side section view illustrating the mode of operation of the spring apparatus of  FIG. 21  when interposed between an opposing pair of vertebra in a spinal column; 
         FIG. 24  is a side view further illustrating the mode of operation of the spring apparatus of  FIG. 21  when compressed between an opposing pair of vertebra in a spinal column; 
         FIG. 25  is a perspective view illustrating still another spring apparatus constructed in accordance with the invention; 
         FIG. 26  is a side section view of a portion of the spring apparatus of  FIG. 25  illustrating the mode of operation thereof; 
         FIG. 27  is a side section view of a portion of the spring apparatus of  FIG. 25  further illustrating the mode of operation thereof; 
         FIG. 28  is a perspective view illustrating a constant force coil leaf spring used in still a further embodiment of the invention; 
         FIG. 29  is a side view illustrating the mode of operation of a constant force spring inserted between an opposing pair of vertebra; 
         FIG. 30  is a side section view illustrating still another embodiment of the spring apparatus of the invention; 
         FIG. 30A  is a front perspective view of the spring apparatus of  FIG. 30 ; 
         FIG. 31  is a side section view illustrating the mode of operation of the spring apparatus of  FIG. 30 ; 
         FIG. 31A  is a front perspective view of the spring apparatus of  FIG. 31 ; 
         FIG. 32  is a perspective view illustrating the manufacture of the spring apparatus of  FIG. 16 ; and, 
         FIG. 33  is a perspective view illustrating a spring apparatus producing in accordance with the manufacturing process illustrating in  FIG. 32 . 
         FIG. 34  is a perspective view illustrating the general relationship of the spine and anatomical planes of the body; 
         FIG. 35  is a perspective view illustrating the use of apparatus to pivot in one rotational direction one member with respect to another adjacent member; 
         FIG. 36  is a perspective view illustrating the use of the apparatus of  FIG. 35  to pivot in one rotational direction one vertebra with respect to an adjacent vertebra; 
         FIG. 37  is a perspective view illustrating the use of apparatus to pivot in at least two rotational directions one member with respect to another adjacent; 
         FIG. 38  is a perspective view illustrating the use of the apparatus of  FIG. 37  to pivot in at least two rotational directions one vertebra with respect to an adjacent vertebra; 
         FIG. 39  is a perspective view illustrating the use of apparatus to pivot in at least two rotational directions and to rotate one member with respect to another adjacent member; 
         FIG. 40  is a perspective view illustrating the use of the apparatus of  FIG. 39  to pivot in at least two rotational directions and to rotate one vertebra with respect to an adjacent vertebra; 
         FIG. 41  is a side elevation view of a portion of a spine illustrating principal nerves that exit the spine; 
         FIG. 42  is a side view illustrating an instrument constructed in accordance with the principles of the invention to minimize the risk of injury to soft tissue and hard tissue while producing an opening in the hard tissue; 
         FIG. 43  is a front view of a portion of a spine illustrating the insertion along a wire of an instrument constructed in accordance with the invention; 
         FIG. 44  is a top view illustrating the mode of operation of the instrument of  FIG. 42 ; 
         FIG. 45  is a front view further illustrating the mode of operation of the instrument of  FIG. 42 ; 
         FIG. 46  is a top view illustrating an instrument construction that is to be avoided in the practice of the invention; 
         FIG. 46A  is a section view illustrating the instrument of  FIG. 46  and taken along section line  46 A- 46 A; 
         FIG. 47  is a top view illustrating an instrument construction that can be utilized in the practice of the invention; 
         FIG. 47A  is a section view illustrating the instrument of  FIG. 47  and taken along section line  47 A- 47 A; 
         FIG. 47B  is a top view illustrating another instrument constructed in accordance with the invention; 
         FIG. 47C  is a side view illustrating the instrument of  FIG. 47B ; 
         FIG. 47D  is a top view illustrating a further instrument constructed in accordance with the invention; 
         FIG. 47E  is a perspective view illustrating the mode of operation of the instrument of  FIG. 47D ; 
         FIG. 48  is a top view illustrating another instrument construction that can be utilized in accordance with the invention; 
         FIG. 48A  is a section view illustrating the instrument of  FIG. 48  and taken along section line  48 A- 48 A; 
         FIG. 49  is a top view illustrating a further instrument construction that can be utilized in the invention; 
         FIG. 49A  is a section view illustrating the instrument of  FIG. 49  and taken along section line  49 A- 49 A; 
         FIG. 50  is a top view further illustrating the insertion of the instrument of  FIG. 43  in an intervertebral disc along a wire; 
         FIG. 51  is a side view further illustrating the instrument of  FIG. 43 ; 
         FIG. 52  is a side view of an instrument that functions both to produce an opening in hard tissue and to insert an implant once the opening has been produced; 
         FIG. 53  is a side view illustrating the apex of a misaligned spine; 
         FIG. 54  is a side view illustrating the apex of another misaligned spine; 
         FIG. 55  is an end view illustrating an intervertebral implant; 
         FIG. 56  is a side view illustrating the implant of  FIG. 55 ; 
         FIG. 57  is a top view illustrating an intervertebral implant; 
         FIG. 58  is a front view illustrating the implant of  FIG. 57 ; 
         FIG. 59  is a bottom view illustrating the implant of  FIG. 57 ; 
         FIG. 60  is a side view illustrating the implant of  FIG. 57 ; 
         FIG. 61  is a back view of the implant of  FIG. 57 ; 
         FIG. 62  is a top view illustrating an intervertebral implant; 
         FIG. 63  is a side view illustrating the implant of  FIG. 62 ; 
         FIG. 64  is a bottom view illustrating the implant of  FIG. 62 ; 
         FIG. 65  is a back view illustrating the implant of  FIG. 62 ; 
         FIG. 66  is a section view illustrating the implant of  FIG. 63  and taken along section line a-a in  FIG. 63 ; 
         FIG. 67  is a top perspective view illustrating the implant of  FIG. 62 ; 
         FIG. 68  is a bottom perspective view illustrating the implant of  FIG. 62 ; 
         FIG. 69  is a bottom view illustrating an intervertebral implant; 
         FIG. 70  is a left hand side view illustrating the implant of  FIG. 69 ; 
         FIG. 71  is a right hand side view illustrating the implant of  FIG. 69 ; 
         FIG. 72  is a top view illustrating the implant of  FIG. 69 ; 
         FIG. 73  is a perspective view illustrating an intervertebral implant having an aperture formed therethrough to receive slidably a guide wire; 
         FIG. 74  is a top view illustrating the implant of  FIG. 73 ; 
         FIG. 75  is a side view illustrating the implant of  FIG. 73 ; 
         FIG. 76  is an end view illustrating the implant of  FIG. 73 ; 
         FIG. 77  is a perspective view illustrating an intervertebral implant; 
         FIG. 78  is a side view illustrating the implant of  FIG. 77 ; 
         FIG. 79  is a top view illustrating the implant of  FIG. 77 ; 
         FIG. 80  is an end view illustrating the implant of  FIG. 77 ; 
         FIG. 81  is a side view illustrating an intervertebral implant; 
         FIG. 82  is an end view illustrating the implant of  FIG. 81 ; 
         FIG. 83  is a top view illustrating the implant of  FIG. 81 ; 
         FIG. 84  is a perspective view illustrating the implant of  FIG. 81 ; 
         FIG. 85  is a back view illustrating the implant of  FIG. 81 ; 
         FIG. 86  is a perspective view illustrating an intervertebral implant; 
         FIG. 87  is a side view of the implant of  FIG. 86 ; 
         FIG. 88  is a perspective view illustrating an intervertebral implant; 
         FIG. 89  is a side view of the implant of  FIG. 88 ; 
         FIG. 90  is an exploded perspective view illustrating an intervertebral implant; 
         FIG. 91  is a side view illustrating a unitary intervertebral implant; 
         FIG. 92  is an end view illustrating the implant of  FIG. 91 ; 
         FIG. 93  is a side view illustrating a unitary intervertebral implant; 
         FIG. 94  is a left hand end view illustrating the implant of  FIG. 93 ; 
         FIG. 95  is a perspective view illustrating a portion of an articulating intervertebral implant; 
         FIG. 96  is a back view illustrating the implant portion of  FIG. 95 ; 
         FIG. 97  is a top view illustrating the implant portion of  FIG. 95 ; 
         FIG. 98  is an end view illustrating the implant portion of  FIG. 95 ; 
         FIG. 99  is a side view illustrating the implant portion of  FIG. 95 ; 
         FIG. 100  is a perspective view illustrating a unitary intervertebral implant; 
         FIG. 101  is an end view illustrating the implant of  FIG. 100 ; 
         FIG. 102  is a side view illustrating the implant of  FIG. 100 ; 
         FIG. 103  is a side view illustrating an intervertebral implant; 
         FIG. 104  is an end view illustrating the implant of  FIG. 103 ; 
         FIG. 105  is a perspective view illustrating an intervertebral implant; 
         FIG. 106  is a side view illustrating the implant of  FIG. 105 ; 
         FIG. 107  is a top view illustrating the implant of  FIG. 105 ; 
         FIG. 108  is an end view illustrating the implant of  FIG. 105 ; 
         FIG. 109  is a front view illustrating the implant of  FIG. 105 ; 
         FIG. 110  is a top view illustrating an articulating intervertebral implant; 
         FIG. 111  is a side view illustrating the implant of  FIG. 110  in alignment to slide down a guide wire; 
         FIG. 112  is a top section view of the implant of  FIG. 110  illustrating internal construction details thereof; 
         FIG. 113  is perspective view illustrating a unitary intervertebral implant; 
         FIG. 114  is a side view illustrating the implant of  FIG. 113 ; 
         FIG. 115  is a top view illustrating the implant of  FIG. 113 ; 
         FIG. 116  is an end view illustrating the implant of  FIG. 113 ; 
         FIG. 117  is a perspective view illustrating a unitary intervertebral implant; 
         FIG. 118  is a side view illustrating the implant of  FIG. 117 ; 
         FIG. 119  is a top view illustrating the implant of  FIG. 117 ; 
         FIG. 120  is an end view illustrating the implant of  FIG. 117 ; 
         FIG. 121  is a perspective view illustrating an unitary intervertebral implant; 
         FIG. 122  is a top view illustrating the implant of  FIG. 121 ; 
         FIG. 123  is a side view of the implant of  FIG. 122 ; 
         FIG. 124  is an end view illustrating the implant of  FIG. 123 ; 
         FIG. 125  is a perspective view illustrating an intervertebral implant; 
         FIG. 126  is a top view illustrating the implant of  FIG. 125 ; 
         FIG. 127  is a side view illustrating the implant of  FIG. 125 ; 
         FIG. 128  is a left hand side view illustrating the implant of  FIG. 127 ; 
         FIG. 129  is a right hand side view illustrating the implant of  FIG. 127 ; 
         FIG. 130  is an exploded ghost view further illustrating the implant of  FIGS. 57 to 61 ; 
         FIG. 131  is a perspective view illustrating a component of the implant of  FIG. 130 ; 
         FIG. 132  is a top view illustrating the component of  FIG. 131 ; 
         FIG. 133  is a section view further illustrating the component of  FIG. 132  and taken along section line A-A thereof; 
         FIG. 134  is a front view illustrating the component of  FIG. 132 ; 
         FIG. 135  is a side view illustrating the component of  FIG. 134 ; 
         FIG. 136  is a bottom view of the component of  FIG. 134 ; 
         FIG. 137  is a perspective view illustrating a component of the implant of  FIG. 130 ; 
         FIG. 138  is a side view illustrating the component of  FIG. 137 ; 
         FIG. 139  is a front view illustrating the component of  FIG. 138 ; 
         FIG. 140  is a bottom view illustrating the component of  FIG. 138 ; 
         FIG. 141  is a bottom perspective view illustrating a component of the implant of  FIG. 130 ; 
         FIG. 142  front view illustrating the component of  FIG. 141  inverted; 
         FIG. 143  is a side view illustrating the component of  FIG. 142 ; 
         FIG. 144  is a section view illustrating the component of  FIG. 143  and taken along section line A-A thereof; 
         FIG. 145  is a bottom view illustrating the component of  FIG. 142 ; 
         FIG. 146  is a front view illustrating a component of the implant of  FIG. 130 ; 
         FIG. 147  is a top view illustrating the component of  FIG. 146 ; 
         FIG. 148  is a side view illustrating the component of  FIG. 146 ; 
         FIG. 149  is a perspective view illustrating the implant of  FIG. 130  assembled and illustrating the mode of operation thereof; 
         FIG. 150  is a side view illustrating another implant constructed in accordance with the invention; 
         FIG. 151  is a top view illustrating the implant of  FIG. 150 ; 
         FIG. 152  is an end view illustrating the implant of  FIG. 151 ; 
         FIG. 153  is a perspective view illustrating the rocker component of the implant of  FIG. 150 ; 
         FIG. 154  is a side view illustrating the rocker component of  FIG. 153 ; 
         FIG. 155  is a bottom view illustrating the rocker component of  FIG. 154 ; 
         FIG. 156  is a front view illustrating the rocker component of  FIG. 154 ; 
         FIG. 157  is a perspective view illustrating the base component of the implant of  FIG. 150 ; 
         FIG. 158  is a top view illustrating the base component of  FIG. 150 ; 
         FIG. 159  is an end view illustrating the base component of  FIG. 158 ; 
         FIG. 160  is a side view illustrating the base component of  FIG. 158 ; 
         FIG. 161  is a top view illustrating a further implant, which implant is similar to the implant of  FIG. 150 ; 
         FIG. 162  is a side view of the implant of  FIG. 161 ; 
         FIG. 163  is a side view rotated ninety degrees clockwise of the implant of  FIG. 161 ; 
         FIG. 164  is a perspective view illustrating still another intervertebral implant; 
         FIG. 165  is a perspective view illustrating still a further intervertebral implant constructed in accordance with the invention to displace transversely one spinal vertebra with respect to an adjacent spinal vertebra; 
         FIG. 166  is a top view illustrating the implant of  FIG. 165 ; 
         FIG. 167  is an end view rotated ninety degrees clockwise illustrating the implant of  FIG. 166 ; 
         FIG. 168  is a side view illustrating the implant of  FIG. 167 ; 
         FIG. 169  is a bottom view illustrating the implant of  FIG. 167 ; 
         FIG. 170  is an exploded ghost view illustrating further construction details of the implant of  FIG. 165 ; 
         FIG. 171  is a perspective ghost view illustrating the implant of  FIG. 165  and the mode of operation thereof; 
         FIG. 172  is a perspective view illustrating yet another implant; 
         FIG. 173  is bottom view illustrating the implant of  FIG. 172 ; 
         FIG. 174  is a back or rear view rotated ninety degrees clockwise illustrating the implant of  FIG. 173 ; 
         FIG. 175  is a front end view rotated ninety degrees counterclockwise illustrating the implant of  FIG. 173 ; 
         FIG. 176  is a side view illustrating the implant of  FIG. 173 ; 
         FIG. 177  is a perspective view illustrating the mode of operation of the implant of  FIG. 173 ; 
         FIG. 178  is a perspective view illustrating an instrument constructed in accordance with the invention; 
         FIG. 179  is a perspective view illustrating the mode of operation of the instrument; 
         FIG. 180  is a perspective view illustrating a floating implant constructed in accordance with the invention; 
         FIG. 181  is an end view further illustrating the implant of  FIG. 180 ; 
         FIG. 182  is a top view further illustrating the implant of  FIG. 180 ; 
         FIG. 183  is a side view of the implant of  FIG. 180  illustrating additional construction details thereof; 
         FIG. 184  is a perspective exploded view illustrating an orthogonal implant system constructed in accordance with the invention; 
         FIG. 185  is a perspective view illustrating an implant insertion instrument; 
         FIG. 186  is a perspective view illustrating an implant utilized to separate a pair of opposing vertebrae; 
         FIG. 187  is a top view illustrating the mode of operation of an instrument constructed in accordance with another embodiment of the invention; 
         FIG. 188  is a perspective view further illustrating the use of the instrument of  FIG. 187 ; 
         FIG. 189  is a side view of a portion of a spine illustrating the use of implants to pivotally adjust vertebrae; 
         FIG. 190  is a front view illustrating an implant inserted between a pair of opposing spinous processes; 
         FIG. 191  is a front view illustrating another implant inserted between a pair of opposing spinous processes; 
         FIG. 192  is a front view illustrating a further implant inserted between a pair of opposing spinous processes; 
         FIG. 193  is a perspective view illustrating an implant inserted between a pair of opposed, adjacent spinous processes; 
         FIG. 194  is a top view of the spinous processes/implant of  FIG. 193  illustrating further details thereof; 
         FIG. 195  is a front view of the spinous processes/implant of  FIG. 193  illustrating additional construction details thereof; 
         FIG. 196  is a side view of the spinous processes/implant of  FIG. 193  illustrating additional construction details thereof; 
         FIG. 197  is a perspective view illustrating an implant including a deployable wing component; 
         FIG. 198  is a perspective view illustrating an alternate embodiment of an implant with a deployable wing component; 
         FIG. 199  is an exploded perspective view illustrating an alternate embodiment of an implant constructed in accordance with the invention; 
         FIG. 200  is a bottom view further illustrating the implant of  FIG. 199 ; 
         FIG. 201  is a side section view taken along section line A-A and further illustrating the implant of  FIG. 200 ; 
         FIG. 202  is an end view further illustrating the implant of  FIG. 200 ; 
         FIG. 203  is a side view further illustrating the implant of  FIG. 200 ; 
         FIG. 204  is a front view illustrating an implant with deployed wings that have an arcuate configuration; 
         FIG. 205  is a front view illustrating an implant having a T-shaped deployed wing; 
         FIG. 206  is a perspective view illustrating a resilient spring implant; 
         FIG. 207  is a perspective view illustrating another resilient spring implant; 
         FIG. 208  is a perspective view illustrating a resilient implant interposed between a pair of adjacent vertebra; 
         FIG. 209  is a perspective view illustrating an ovate resilient implant; 
         FIG. 210  is a perspective view illustrating a resilient implant with a concave upper surface; 
         FIG. 211  is a perspective view illustrating a resilient implant with an expanding groove formed therein; 
         FIG. 212  is a perspective view illustrating a resilient implant with a tooth extending outwardly from the upper surface thereof; 
         FIG. 212A  is a perspective view illustrating a resilient implant with a toothed opening than initially narrows and then widens; 
         FIG. 213  is a perspective view illustrating an instrument including a distal end having a cam surface usable to separate, penetrate, or cut tissue; 
         FIG. 214  is a perspective exploded view illustrating an implant comprised of a pair of interlocking members; 
         FIG. 215  is a side view illustrating an instrument utilized to cut tissue; 
         FIG. 216  is a front view further illustrating the instrument of  FIG. 215 ; 
         FIG. 217  is a top view illustrating the instrument of  FIG. 215 ; 
         FIG. 217A  is a back view illustrating the instrument of  FIG. 215 ; 
         FIG. 218  is a front view illustrating an instrument utilized to cut tissue; 
         FIG. 219  is a side view illustrating the instrument of  FIG. 218 ; 
         FIG. 220  is a back end view illustrating the instrument of  FIG. 218 ; 
         FIG. 221  is a top view illustrating the instrument of  FIG. 218 ; 
         FIG. 222  is a top view illustrating an instrument utilized to cut tissue; 
         FIG. 223  is a side view illustrating the instrument of  FIG. 222 ; 
         FIG. 224  is a front view illustrating the instrument of  FIG. 222 ; 
         FIG. 225  is a section view further illustrating construction details of the instrument of  FIG. 223  and taken along section line V-V thereof; 
         FIG. 226  is a perspective view illustrating the instrument of  FIG. 222 ; 
         FIG. 227  is a back view illustrating the instrument of  FIG. 226 ; 
         FIG. 227A  is a top view illustrating an instrument that can be slid along a wire to separate, pass through, cut, or resect tissue; 
         FIG. 227B  is a left hand end view further illustrating the instrument of  FIG. 227A ; 
         FIG. 228  is a section view illustrating the distal implant delivery end of the instrument illustrated in  FIGS. 230 and 231 ; 
         FIG. 229  is a front view illustrating the instrument delivery end of  FIG. 228 ; 
         FIG. 230  is a side view illustrating an instrument utilized to insert implants in accordance with the invention; 
         FIG. 231  is a back view illustrating the instrument of  FIG. 230 ; 
         FIG. 231A  is a side view of an instrument that can be utilized alone or in conjunction with the instrument illustrated in  FIG. 230 ; 
         FIG. 231B  is a left hand end view of the instrument of  FIG. 231A ; 
         FIG. 231C  is an exploded view illustrating the instrument of  FIG. 231A  utilized in conjunction with the instrument of  FIG. 230 ; 
         FIG. 231D  is a top view illustrating the instrument of  FIG. 231A  assembly with the instrument of  FIG. 230 ; 
         FIG. 231E  is a right hand side view illustrating the assembled instruments of  FIG. 231D ; 
         FIG. 232  is a perspective view illustrating an instrument utilized to separate tissue, cut tissue, or penetrate tissue; 
         FIG. 233  is a side section view illustrating the instrument of  FIG. 232  and taken along section line A-A of  FIG. 235 ; 
         FIG. 234  is a back view illustrating the instrument of  FIG. 232 ; 
         FIG. 235  is a front view illustrating the instrument of  FIG. 233 ; 
         FIG. 235A  is a perspective view illustrating an instrument utilized to separate tissue, cut tissue, or penetrate tissue; 
         FIG. 235B  is an inverted left hand end view illustrating the instrument of  FIG. 235A ; 
         FIG. 235C  is a section view illustrating the instrument of  FIG. 235B  and taken along section line A-A thereof; 
         FIG. 235D  is a right hand end view illustrating the instrument of  FIG. 235C ; 
         FIG. 235E  is a perspective partial section view illustrating a hollow instrument including a plunger mounted slidably therein to eject an implant or to create suction to draw an implant or tissue into the instrument; 
         FIG. 235F  is a top view illustrating the positioning of an instrument relative to a nerve prior to using the instrument to laterally displace the nerve in cam-like fashion to safely advance the instrument past the nerve toward a spinal disc; 
         FIG. 235G  is a side view illustrating the instrument, nerve, and disc of  FIG. 235F ; 
         FIG. 235H  is a side view illustrating the instrument, nerve, and disc of  FIG. 235H  after the instrument has been rotated to laterally displace the nerve and has been advanced to a position where the tip of the instrument is adjacent and generally conforms to the periphery of the disc; 
         FIG. 235I  is a perspective view illustrating the positioning of an instrument adjacent a nerve prior to rotating the instrument to displace the nerve in cam-like fashion; 
         FIG. 236  is a top view illustrating an implant constructed in accordance with the invention to slide along a guide wire and/or along a hollow guide unit; 
         FIG. 237  is a side view illustrating the implant of  FIG. 236 ; 
         FIG. 238  is a front view illustrating the implant of  FIG. 236 ; 
         FIG. 239  is a back end view illustrating the implant of  FIG. 237 ; 
         FIG. 240  is a perspective view illustrating the implant of  FIG. 236 ; 
         FIG. 241  is a perspective view illustrating the implant of  FIG. 236 ; 
         FIG. 242  is a top view illustrating an implant constructed to slide along a guide wire and/or along a hollow guide unit; 
         FIG. 243  is a front end view illustrating the implant of  FIG. 242 ; 
         FIG. 244  is a left-hand side view illustrating the implant of  FIG. 242 ; 
         FIG. 245  is a back end view illustrating the implant of  FIG. 242 ; 
         FIG. 246  is a right-hand side view illustrating the implant of  FIG. 242 ; 
         FIG. 247  is a perspective view illustrating the implant of  FIG. 242 ; 
         FIG. 248  is a perspective view illustrating the implant of  FIG. 242 ; 
         FIG. 249  is a perspective view illustrating an implant constructed to slide along a guide wire and/or along a hollow guide unit; 
         FIG. 250  is a front end view illustrating the implant of  FIG. 249 ; 
         FIG. 251  is a top view illustrating the implant of  FIG. 249 ; 
         FIG. 252  is a side view illustrating the implant of  FIG. 251 ; 
         FIG. 253  is a top view illustrating an implant constructed to slide along a guide wire and/or along a hollow guide unit; 
         FIG. 254  is a left-hand side view illustrating the implant of  FIG. 253 ; 
         FIG. 255  is a front end view illustrating the implant of  FIG. 253 ; 
         FIG. 256  is a back end view illustrating the implant of  FIG. 253 ; 
         FIG. 257  is a right-hand side view illustrating the implant of  FIG. 253 ; 
         FIG. 258  is a perspective view illustrating the implant of  FIG. 253 ; 
         FIG. 259  is a perspective view illustrating the implant of  FIG. 253 ; 
         FIG. 260  is a top view illustrating an implant constructed to slide along a guide wire and/or along a hollow guide unit; 
         FIG. 261  is a left-hand side view illustrating the implant of  FIG. 260 ; 
         FIG. 262  is a right-hand side view illustrating the implant of  FIG. 260 ; 
         FIG. 263  is a back end view illustrating the implant of  FIG. 260 ; 
         FIG. 264  is a front end view illustrating the implant of  FIG. 260 ; 
         FIG. 265  is a bottom view illustrating the implant of  FIG. 260 ; 
         FIG. 266  is a perspective view illustrating the implant of  FIG. 260 ; 
         FIG. 267  is a perspective view illustrating the implant of  FIG. 260 ; 
         FIG. 268  is a top view illustrating an articulating implant constructed to slide along a guide wire and/or along a hollow guide unit; 
         FIG. 269  is a back end view illustrating the implant of  FIG. 268 ; 
         FIG. 270  is a side view illustrating the implant of  FIG. 268 ; 
         FIG. 271  is a perspective view illustrating the implant of  FIG. 268 ; 
         FIG. 272  is a perspective view illustrating the implant of  FIG. 268 ; 
         FIG. 273  is a top view illustrating an articulating implant constructed in accordance with the invention; 
         FIG. 274  is a side view illustrating the implant of  FIG. 273 ; 
         FIG. 275  is a section view illustrating the implant of  FIG. 274  illustrating constructions details thereof and taken along section line A-A; 
         FIG. 276  is a top view illustrating another articulating implant constructed in accordance with the invention and in a linear configuration; 
         FIG. 277  is a side view illustrating the implant of  FIG. 276 ; 
         FIG. 278  is a perspective view illustrating the implant of  FIG. 276 ; 
         FIG. 279  is a top view illustrating the implant of  FIG. 276  in an articulated orientation; 
         FIG. 280  is a side view illustrating the articulated implant of  FIG. 279 ; 
         FIG. 281  is a perspective view illustrated in the articulated implant of  FIG. 279 ; 
         FIG. 282  is a top view illustrating an implant constructed in accordance with an alternate embodiment of the invention; 
         FIG. 283  is a top view of the implant of  FIG. 282  illustrating the mode of operation thereof; 
         FIG. 284  is a top view illustrating an implant constructed in accordance with another embodiment of the invention; 
         FIG. 285  is a top view of the implant of  FIG. 284  illustrating the mode of operation thereof; 
         FIG. 286  is a top view illustrating an implant constructed in accordance with a further embodiment of the invention; and, 
         FIG. 287  is a top view of the implant of  FIG. 286  illustrating the mode of operation thereof. 
     
    
    
     Briefly, in accordance with the invention, provided is an improved method to manipulate a damaged intervertebral disc to improve the functioning of the disc. The disc includes an annulus. The method comprises the steps of providing a device to alter, when inserted in the disc, the shape and dimension of the disc; and, inserting the device in the disc to alter said shape and dimension of the disc. The disc is intermediate a first and a second vertebra. The first vertebra has a bottom adjacent the disc and the second vertebra has a top adjacent the disc. The device alters the shape and dimension of the disc by internal traction to increase the height (H) of the disc along an axis (G) generally normal to the bottom of the first vertebra and the top of the second vertebra. The device can also alter the shape and dimension of the disc by internal traction to decrease the width (W) of the disc. The device can further alter the shape and dimension of the disc by internal traction changing the pressure in the disc. 
     In another embodiment of the invention, provided is an improved method for inserting a device to improve in an individual&#39;s body the functioning of a damaged intervertebral disc, including an annulus, between a pair of vertebra, the body having a front, a first side, a second side, and a back. The disc includes a front portion facing the front of the body, side portions each facing a side of the body, and a back portion facing the back of the body. The vertebrae are in a pre-existing spaced apart configuration with respect to each other. The improved method comprises the steps of forming an opening in the disc between the pair of vertebrae, and in one of a group consisting of the side portions of the disc, the front portion of the disc, and the back portion of the disc; providing a support device shaped and dimensioned to fit through the opening in the disc; and, inserting the support device through the opening in the disc without enlarging the pre-existing spaced apart configuration of the pair of vertebrae. 
     In a further embodiment of the invention, provided is an improved method inserting a device to improve in an individual&#39;s body the functioning of a damaged intervertebral disc, including an annulus, between a pair of vertebrae. The individual&#39;s body has a front, a first side, a second side, and a back. The disc includes a front portion facing the front of the body, side portions each facing a side of the body, a back portion facing the back of the body, and a pre-existing rupture. The vertebrae are in a pre-existing spaced apart configuration with respect to each other. The method comprises the steps of providing a support device shaped and dimensioned to fit through the pre-existing rupture in the disc; and, inserting the support device through the pre-existing rupture in the disc without enlarging the pre-existing spaced apart configuration of the pair of vertebrae. 
     In a still further embodiment of the invention, provided is an improved method to manipulate a damaged intervertebral disc to improve the functioning of the disc. The disc includes an annulus. The improved method comprises the step of inserting a device in the disc, the device operable to apply a force to the disc. The method also comprises the step of operating the device to apply a force to the disc. 
     In still another embodiment of the invention, provided is an improved method to improve the functioning of a damaged intervertebral disc positioned between, contacting, and separating a pair of vertebrae. The disc includes an annulus. The method comprises the steps of providing a device shaped and dimensioned when inserted in the disc to contact each of the vertebrae, and operable in response to movement of the vertebrae to permit simultaneous polyaxial movement of the vertebrae and said device; and, inserting the device in the disc to contact each of the vertebrae. 
     In a further embodiment of the invention, provided is an improved apparatus for disposition between first and second opposing vertebrae. The first vertebra is canted with respect to the second vertebra. The apparatus is shaped and dimensioned to generate a force to change the cant of the first vertebra with respect to the second vertebra. 
     In another embodiment of the invention, provided is improved apparatus for disposition between first and second opposing vertebrae. The first vertebra is rotated about a vertical axis from a first desired position to a second misaligned position. The apparatus is shaped and dimensioned to generate a force to rotate said first vertebra from the second misaligned position toward the first desired position. 
     In another embodiment of the invention, provided is an apparatus to manipulate an intervertebral disc to improve the functioning of the disc, the disc including an annulus, between a pair of vertebra, comprising a device configured when inserted in the disc to contact the vertebra, and operable in response to movement of the vertebra to change the shape of the disc. 
     In another embodiment of the invention, provided is an apparatus to manipulate an intervertebral disc to improve the functioning of the disc, said apparatus shaped and dimensioned such that when said apparatus is inserted in the disc and compressed between a pair of vertebra, said apparatus gathers at least a portion of the disc to offset at least in part expansive forces acting on the disc. The apparatus can be unitary; can roll over at least one of the vertebra when compressed between the vertebra; can slide over at least a portion of one of the vertebra when compressed between the vertebra; can lengthen inwardly when compressed between the vertebra; can coil inwardly when compressed between the vertebra; and, can fixedly engage at least one of the vertebra when compressed. 
     In another embodiment of the invention, provide is an apparatus to manipulate an intervertebral disc to improve the functioning of the disc, said apparatus shaped and dimensioned such that when said apparatus is inserted in the disc and compressed between a pair of vertebra, at least a portion of said apparatus moves away from the periphery of the disc. 
     In another embodiment of the invention, provided is an improved method to manipulate an intervertebral disc to improve the functioning of the disc, the disc including an annulus, between a pair of vertebra. The method comprises the steps of providing a device shaped and dimensioned when inserted in the disc to contact the vertebra, and operable in response to movement of the vertebra to change the shape of the disc; and, inserting said device in the disc to change the shape of the disc. 
     In another embodiment of the invention, provided is an improved method to manipulate an intervertebral disc to improve the functioning of the disc. The method comprises the steps of providing an apparatus shaped and dimensioned when inserted in the disc and compressed between a pair of vertebra to gather at least a portion of the disc to offset at least in part expansive forces acting on the disc; and, inserting the apparatus in the disc to gather said portion of the disc when the apparatus is compressed between a pair of the vertebra. The apparatus can be unitary; can roll over at least one of the vertebra when compressed between the vertebra; can slide over at least a portion of one of the vertebra when compressed between the vertebra; can lengthen inwardly when compressed between the vertebra; can coil inwardly when compressed between the vertebra; and, can fixedly engage at least one of the vertebra when compressed. 
     In a further embodiment of the invention, provided is an improved method to manipulate an intervertebral disc to improve the functioning of the disc. The disc includes a periphery. The method comprises the steps of providing an apparatus shaped and dimensioned when inserted in the disc and compressed between a pair of vertebra to move at least a portion of the apparatus away from the periphery of the disc; and, inserting the apparatus in the disc to move said portion of said apparatus when the apparatus is compressed between a pair of said vertebra. 
     In another embodiment of the invention, provided is an improved method for inserting a device to improve in an individual&#39;s body the functioning of an intervertebral disc, including an annulus, between a pair of vertebra, the body having a front, a first side, a second side, and a back. The disc includes a front portion facing the front of the body, side portions each facing a side of the body, and a back portion facing the back of the body. The improved method comprises the steps of forming an opening in the disc between the pair of vertebrae, and in one of a group consisting of the side portions of the disc, the front portion of the disc, and the back portion of the disc; providing a device shaped and dimensioned to fit through the opening in the disc; and, inserting the device through the opening in the disc and retaining substantially all of the disc. 
     In a further embodiment of the invention, provided is an improved method for inserting a device to improve in an individual&#39;s body the functioning of an intervertebral disc, including an annulus, between a pair of vertebrae. The individual&#39;s body has a front, a first side, a second side, and a back. The disc includes a front portion facing the front of the body, side portions each facing a side of the body, a back portion facing the back of the body, and a pre-existing rupture. The method comprises the steps of providing a device shaped and dimensioned to fit through the pre-existing rupture in the disc; and, inserting the device through the pre-existing rupture in the disc and retaining substantially all of the disc. 
     Provided in another embodiment of the invention is an improved method to separate tissue. The improved method comprises the steps of providing an instrument shaped and dimensioned to oscillate within tissue around nerves and vasculature; and, oscillating the instrument within tissue around nerves and vasculature. 
     In another embodiment of the invention, provided is an improved method to form an opening in an intervertebral disc. The method comprises the steps of providing an instrument shaped and dimensioned to oscillate within the intervertebral disc; and, oscillating the instrument within an intervertebral disc. 
     In a further embodiment of the invention, provided is an improved method to widen an opening in an intervertebral disc. The method comprises the steps of providing an instrument shaped and dimensioned to oscillate within the intervertebral disc; and, oscillating the instrument within the intervertebral disc. 
     In still another embodiment of the invention, provided is an improved method for forming an opening in hard tissue while minimizing the risk of injury to principal vasculature and nerves. The method comprises the steps of providing an instrument with a distal end shaped and dimensioned to penetrate, when oscillated in and out, soft tissue; and, shaped and dimensioned, when contacting a principal vasculature or nerve, to prevent said distal end from cutting or piercing the principal vasculature or nerve, and to enable the distal end to move past the principal vasculature or nerve. The distal end moves past the principal vasculature or nerve by being oscillated in directions toward and away from the vessel, and by being laterally displaced. When the distal end contacts and is impeded by the principal vasculature or nerve, a resistance to movement of the distal end is generated that, along with the location of the distal end, indicates that the distal end has contacted the principal vasculature or nerve. The method also comprises the steps of oscillating the distal end to pass through the soft tissue; of, when contacting the principal vasculature or nerve, laterally displacing and oscillating the distal end to move the distal end past the principal vasculature or nerve; and, of contacting the hard tissue and oscillating the distal end against the hard tissue to form an opening therein. 
     In still a further embodiment of the invention, provided is an improved method for forming an opening in hard tissue. The method comprises the steps of providing an instrument with a distal end shaped and dimensioned to penetrate, when oscillated in and out, soft tissue and hard tissue; of oscillating the distal end to pass through the soft tissue to contact the hard tissue; and, of oscillating the distal end against the hard tissue to form an opening therein. 
     In yet another embodiment of the invention, provided is an improved method for detecting principal vasculature and nerves. The improved method comprises the steps of providing an instrument with a distal end. The distal end is shaped and dimensioned to penetrate, when oscillated in and out, soft tissue; and, when contacting a principal circulatory/neural vessel, to prevent the distal end from cutting or piercing the principle circulatory/neural vessel. When the distal end contacts and is impeded by a principal vasculature or nerve, a resistance is generated that indicates that the distal end has contacted a principal circulatory/neural vessel. The method also comprises the step of oscillating the distal end to pass through the soft tissue until the resistance indicates that the distal end is contacting a principle circulatory/neural vessel. 
     In yet a further embodiment of the invention, provided is an improved apparatus for forming an opening in hard tissue. The apparatus comprises an instrument with a tissue contacting rounded distal end shaped and dimensioned to penetrate, when oscillated, hard tissue. The distal end can be shaped and dimensioned, when contacting a principal vasculature or nerve, to prevent the distal end from cutting or piercing the principal vasculature or nerve, and to enable the distal end to move past the principal vasculature or nerve. 
     In yet still another embodiment of the invention, provided is an improved method of passing an implant through tissue to an intervertebral disc location. The method comprises the steps of providing an elongate guide unit; providing an implant structure shaped and dimensioned to pass through tissue and move along the guide unit; and, moving the implant structure through tissue along the guide unit to the intervertebral disc location. 
     In another embodiment of the invention, provided is an improved method to treat a misaligned spine. The method comprises the steps of providing an implant shaped and dimensioned to slide down a guide wire to a selected position intermediate a pair of vertebra to contact and alter the alignment of said vertebra; and, sliding the implant down a guide wire to the selected position. 
     In a further embodiment of the invention, provided is an improved method to treat a misaligned spine. The method comprises the steps of providing a guide member; providing an articulated implant shaped and dimensioned to slide down and off the guide member in a first orientation to a first selected position intermediate a pair of vertebra, to articulate to a second orientation and be pushed along a path of travel to a second selected position intermediate the pair of vertebra; sliding the implant down the guide member to the first selected position; and, pushing the implant in the second orientation along the path of travel to the second selected position. 
     In still another embodiment of the invention, provided is an improved method to insert an implant intermediate a pair of vertebra. The method comprises the steps of providing an articulated implant shaped and dimensioned to be pushed along an arcuate path of travel to a selected position intermediate the pair of vertebra; inserting the implant intermediate the pair of vertebra; and, pushing the implant along the arcuate path of travel to the second selected position. 
     In still a further embodiment of the invention, provided is an improved method to insert an implant intermediate a pair of vertebra. The method comprises the steps of providing a guide wire having a distal end; providing a spinal implant shaped and dimensioned to slide along said guide wire to a selected position intermediate the pair of vertebra; inserting the guide wire to position the distal end adjacent the pair of vertebra; sliding the spinal implant along the guide wire to the selected position; and, removing the guide wire. 
     In yet still another embodiment of the invention, provided is an improved method to treat a misaligned spine. The method comprises the steps of determining the apex of the misaligned spine; selecting an adjacent pair of vertebra, at least one of the pair of vertebra being located at the apex; determining at least one direction in which to move at least one of the pair of vertebra to correct at least partially the misalignment of the spine; determining a spinal implant shape and dimension to achieve movement of the at least one of the pair of vertebra to correct at least partially misalignment of the spine; providing a selected spinal implant having the shape and dimension; determining a location intermediate the adjacent pair of vertebra at which to position the selected spinal implant to achieve the movement of the at least one of the pair of vertebra; and, inserting the selected spinal implant at the location. 
     In yet still a further embodiment of the invention, provided is an improved method to alter the alignment of a vertebra. The improved method comprises the steps of identifying a disc space location adjacent the vertebra; identifying a spinal implant shape and dimension to generate a force acting from the disc space to alter alignment of the vertebra; providing a selected spinal implant having the shape and dimension; and, inserting the selected spinal implant in the disc space. 
     In another embodiment of the invention, provided is an improved method for inserting an implant. The method comprises the steps of providing an implant; providing a guide member shaped and dimensioned to permit the implant to move along the guide member without rotating on the guide member; and, moving the implant along the guide member to a selected location in a patient&#39;s body. 
     In a further embodiment of the invention, provided is an improved method for fixing an implant adjacent tissue in the body of a patient. The method comprises the steps of forming an implant with an outer surface having at least one opening that expands in size as the distance from the outer surface into the opening increases; and, inserting the implant adjacent viscoelastic tissue in the body to permit the tissue to move into the opening and expand inside the opening. 
     In still another embodiment of the invention, provided is an improved method to align vertebrae. The method includes the steps of providing an implant that aligns a pair of adjacent vertebra and permits movement of the pair of adjacent vertebra while, to protect the facets of said vertebrae, minimizing rotation of one of the vertebra with respect to the other of the vertebra; and, inserting the implant between the pair of vertebra to engage each of the pair of vertebra, alter the alignment of the vertebrae, permit movement of the vertebrae, and minimize rotation of one of the vertebrae with respect to the other of the vertebrae. The rotation of one of the vertebra about the longitudinal axis of the spine with respect to the other of the vertebra is limited by the implant to fifteen degrees or less, preferably ten degrees or less, and most preferably five degrees or less. If desired, the implant can restrict rotation of one of the vertebra about the longitudinal axis of the spine with respect to the other of the vertebra to three degrees or less. 
     In still a further embodiment of the invention, provided is an improved method to insert an implant having at least one moving component. The method comprises the steps of providing a guide member to engage and insert the implant while immobilizing the moving component, and once the implant is inserted, to disengage from the implant and permit the moving component to move; engaging the implant with the guide member to immobilize the moving component; inserting the implant with the guide member; and, disengaging the guide member from the implant to permit movement of the moving component. 
     In yet still another embodiment of the invention, provided is an improved method to alter the alignment of the spine. The method comprises the steps of providing an implant shaped and dimensioned to engage each one of an adjacent pair of vertebra and including at least one displaceable member to translate laterally at least one of the pair with respect to the other of the pair; inserting the implant intermediate the pair of vertebra to engage each of the pair; and, displacing the member to translate laterally at least one of the pair. 
     In yet still a further embodiment of the invention, provided is a method to position a pair of opposing tissue surfaces. The method comprises the steps of providing an implant comprised of at least an upper and a lower arcuate concave surface, the surfaces each contacting a different one of said tissue surfaces to space apart the surfaces; and, inserting the implant intermediate the opposing tissue surfaces. 
     In another embodiment of the invention, provided is a method to form an opening within the body. The method comprises the steps of providing an instrument with a distal end shaped and dimensioned to be manipulated to pass through tissue to a selected location within the body, and, housing a deployable instrument to make an opening; manipulating the distal end to pass through tissue to the selected location; deploying the instrument; and making an opening. 
     In a further embodiment of the invention, provided is a method to fix an implant to at least one tissue surface. The method comprises the steps of providing an implant having a surface and at least one opening formed in the surface and increasing in width as the distance from the surface increases; packing the opening with a composition; and, inserting the implant adjacent the tissue surface such that the composition contacts the tissue surface. 
     In still another embodiment of the invention, provided is an improved method to fix an implant to at least one tissue surface. The method comprises the steps of providing an implant having a surface and an arm extending outwardly from the surface and shaped and dimensioned to penetrate and interlock with the tissue surface; and, inserting the implant adjacent the tissue surface such that the arm penetrates and interlocks with the tissue surface. 
     In still a further embodiment of the invention, provided is an improved method of passing an implant through tissue to a location intermediate a pair of opposing joint members. The method comprises the steps of providing an elongate guide unit; providing an implant structure shaped and dimensioned to pass through tissue and move along the guide unit; and, moving the implant structure through tissue along the guide unit to the location intermediate the joint members. The guide unit and implant can be shaped and dimensioned such that the guide unit can prevents rotation of the implant about the longitudinal axis of the guide unit. 
     In yet still another embodiment of the invention, provided is a method to position a pair of opposing tissue surfaces. The method includes the steps of providing a pivot and a guide unit; and, inserting the pivot along the guide unit intermediate the opposing tissue surfaces. 
     In yet still a further embodiment of the invention, provided is an improved method to form a passageway within the body. The method comprises the steps of providing a guide wire; providing an instrument adapted to move along the guide wire and including a distal end shaped and dimensioned to pass through tissue to a selected location between two vertebrae; moving the instrument along the guide wire and manipulating the instrument to pass through tissue to the selected location; and, oscillating the instrument to form a passageway. 
     In another embodiment of the invention, provided is an improved method to alter the orientation of a vertebra. The method comprises the steps of providing a guide wire; providing an instrument adapted to move along the guide wire and including a distal end shaped and dimensioned to pass through tissue to a selected location between two vertebrae; moving the instrument along the guide wire and manipulating the instrument to pass through tissue to the selected location; and, manipulating the instrument to alter the orientation of one of the vertebrae with respect to the other of the vertebrae. 
     In a further embodiment of the invention, provided is an improved method of fixing an implant intermediate an adjacent pair of vertebra. The method comprises the steps of inserting a first implant within an intervertebral disc between the pair of vertebra; inserting a second implant exterior of the intervertebral disc and between the pair of vertebra such that at least one of the vertebra pivots about at least one of the first and second implants to apply a force to the one of the implants between the vertebra. 
     In still another embodiment of the invention, provided is an improved method of fixing an implant intermediate an adjacent pair of vertebra. The method comprises the steps of inserting a first implant within an intervertebral disc between the pair of vertebra; and, inserting a second implant within an intervertebral disc between the pair of vertebra such that at least one of the vertebra pivots about at least one of the first and second implants to apply a force to the one of said implants between the vertebra. 
     In still a further embodiment of the invention, provided is a method of passing an implant through tissue to a location intermediate a pair of joint members. The method comprises the steps of providing an elongate guide unit having a longitudinal axis; providing an implant shaped and dimensioned to move along the guide unit; moving the implant structure along the guide unit to the location intermediate one of a pair comprising an opposing pair of spinous processes, and an opposing pair of facet joints. 
     In yet still another embodiment of the invention, provided is an improved method of passing an implant through tissue to a location intermediate a pair of opposing vertebra. The method comprises the steps of providing an elongate guide unit having a longitudinal axis; providing an implant shaped and dimensioned to move along the guide unit; and, moving the implant structure along the guide unit to the location intermediate the opposing vertebra. The implant and the guide unit are shaped and dimensioned such that the guide unit prevents rotation of the implant about the longitudinal axis of the guide unit. 
     In yet still a further embodiment of the invention, provided is an improved method to position a pair of opposing tissue surfaces. The method comprises the steps of providing a guide wire; providing an implant shaped and dimensioned to move along the guide wire and comprised of at least one tapered end to separate tissue, an upper surface and a lower surface, and an outwardly projecting lip intermediate said upper and lower surfaces; moving the implant along the guide wire to insert the implant intermediate the opposing tissue surfaces such that the upper surface and the lower surface each contact a different one of the tissue surfaces to space apart the tissue surfaces. 
     In another embodiment of the invention, provided is an improved method to position an implant between a pair of opposing tissue surfaces. The method comprises the steps of providing an elongate guide unit having a dispensing end; providing an implant comprised of at least one articulating joint, and shaped and dimensioned to move along the elongate guide unit, to exit the elongate guide unit from the dispensing end and articulate to travel along an arcuate path intermediate the pair of opposing tissue surfaces; moving the implant along the elongate guide unit; exiting the implant from the dispensing end of the guide unit intermediate the opposing tissue surfaces; and, articulating the implant to travel intermediate the pair of opposing tissue surfaces on exiting said elongate guide unit. 
     In a further embodiment of the invention, provided is an improved method to separate a pair of joint members. The method comprises the steps of inserting a first member intermediate the pair of joint members to fixedly engage one of the pair of joint members; and moving a second member between the first member and the other of the pair of joint members to separate the joint members. 
     In still another embodiment of the invention, provided is an improved method for securing an implant between a pair of joint members. The method comprises the steps of providing a contoured implant with outer surfaces shaped and dimensioned to permit each of the joint members to seat on the implant; and, inserting the contoured implant intermediate the pair of joint members such that each of the joint members seats on the implant. 
     In still a further embodiment of the invention, provided is an improved method to restrict motion of one process with respect to another process of the spine about the longitudinal axis of the spine. The method comprises the steps of providing, for one of a pair consisting of two opposing spinous processes and two opposing transverse processes, a contoured implant with outer surfaces shaped and dimensioned to permit each one of the processes in the one of the pair to seat on the implant to restrict rotation or translation of one of the processes with respect to the other of the processes. The method also includes the step of inserting the contoured implant intermediate the opposing processes such that each of the processes seats on the implant to restrict at least one of a pair consisting of rotation and translation of one of the processes with respect to the other of the processes. 
     In yet another embodiment of the invention, provided is a method for securing an implant between an opposing pair of spinous processes of a spine. The method comprises the steps of inserting the implant intermediate the spinous processes; and securing the implant with at least one leg having a first end pivotally attached to the implant, and a second end attached to the spine. 
     In yet a further embodiment of the invention, provided is a method for securing an implant between an opposing pair of joint members. The method comprises the steps of providing a winged implant with at least one wing movable between a stowed position and a deployed position; providing the winged implant with the wing is the stowed position; inserting the winged implant between the opposing pair of joint members; and, moving the wing from the stowed position to the deployed position. 
     In yet still another embodiment of the invention, provided is an improved method to position a device at a selected location in a body to function as an implant. The method comprises the steps of providing a structure constructed to be utilized as an instrument and as an implant; utilizing the structure as an instrument to position the structure at the selected location in the body; and, leaving the structure at the selected location to function as an implant. 
     In one embodiment of the invention, provided is an improved method of altering the tilt of one joint member with respect to another opposing joint member. The method comprises the steps of providing a resilient implant; providing a guide unit; inserting and manipulating the guide unit to tilt one of the opposing joint members; and, sliding the resilient implant along the guide unit intermediate the joint members. 
     In another embodiment of the invention, provided is an improved method of altering the tilt of one joint member with respect to another opposing joint member. The method comprises the steps of providing a spring; providing a guide unit; and, sliding the spring along the guide unit to a selected position intermediate the opposing joint members. 
     In still another embodiment of the invention, provided is an improved method of dampening the load in a joint. The method comprises the steps of providing a resilient implant and an elongate guide unit; sliding the resilient implant along the guide unit; manipulating the guide unit adjacent the joint; and, dispensing the implant into the joint. 
     In yet another embodiment of the invention, provided is an improved method of dampening the load in a joint comprising the step of inserting an ovate coil spring in the joint. 
     In yet still another embodiment of the invention, provided is an improved method of dampening the load in a joint including a pair of opposing joint members. The method comprises the steps of providing a spring and an elongate guide unit; and, sliding the spring along the guide unit intermediate the joint members. 
     In a further embodiment of the invention, provided is an improved method of fixing an implant in a joint. The method comprises the steps of inserting an implant having an outer surface, and at least one opening having a portion in which the width diverges as the distance into the opening from the outer surface of the implant increases. 
     In still a further embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue with an initial color. The method comprises the steps of detecting a change in color; and, inserting the implant in the joint. 
     In yet a further embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue with an initial contrast. The method comprises the steps of detecting a change in contrast; and, inserting the implant in the joint. 
     In yet still a further embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue with an initial hardness. The method comprises the steps of detecting a change in hardness; and, inserting the implant in the joint. 
     In another embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue with an initial elasticity. The method comprises the steps of detecting a change in elasticity; and, inserting the implant in the joint. 
     In still another embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue with an initial texture. The method comprises the steps of detecting a change in texture; and, inserting the implant in the joint. 
     In yet another embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue with an initial color. The method comprises the steps of staining the tissue to change the color of the tissue from the initial color; detecting the change in color; and, inserting the implant. 
     In yet still another embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue having an initial color. The method comprises the steps of removing tissue to change the color of the tissue from the initial color; detecting the change in color; and, inserting the implant. 
     In an additional embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue having an initial texture. The method comprises the steps of changing the texture of the tissue; detecting the change in texture; and, inserting the implant. 
     In still an additional embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue having an initial contrast. The method comprises the steps of changing the contrast of the tissue; detecting the change in contrast; and, inserting the implant. 
     In yet an additional embodiment of the invention, provided is an improved method of passing with an instrument by tissue comprising principal vasculature and nerves. The instrument has a portion with an offset axis of rotation such that a first section of the instrument to one side of the axis of rotation is wider than a second section of the instrument to the other side of the axis of rotation. The method comprising the steps of positioning the instrument with the second section of the instrument adjacent the tissue; and, rotating the instrument about the axis of rotation to contact and displace the tissue with the first section of the instrument. 
     In yet still an additional embodiment of the invention, provided is an improved method of passing an instrument by tissue comprising principal vasculature and nerves. The instrument has a tapered portion with a width diverging from a smaller first section to a larger second section, the tapered portion having and circumscribing an elongate axis of displacement. The method comprises the steps of positioning the instrument with the smaller first section of the instrument adjacent the tissue; and, displacing the instrument in a direction parallel to the axis of displacement to contact and displace the tissue with the larger second section of the instrument. 
     In another embodiment of the invention, provided is an improved method of dissecting tissue with an instrument. The instrument has a cutting portion with an offset axis of rotation such that a first section of the cutting portion to one side of the axis of rotation is wider than a second section of the cutting portion to the other side of the axis of rotation. The method comprises the steps of positioning the instrument with the second section of the instrument adjacent tissue; and, rotating the instrument about the axis of rotation to contact and cut the tissue with the first section of the instrument. 
     In still another embodiment of the invention, provided is an improved method of cutting tissue with an instrument. The instrument has an axis of rotation. The method comprises the steps of sliding the instrument along an elongate guide unit to a position adjacent the tissue; and, rotating the instrument about the axis of rotation and circumscribing an elongate axis of displacement to contact and cut the tissue. 
     In yet still another embodiment of the invention, provided is an improved method of cutting tissue with an instrument. The instrument has a tapered portion with a width diverging from a smaller first section to a larger second cutting section, the tapered portion having and circumscribing an elongate axis of displacement. The method comprises the steps of positioning the instrument with the smaller first section of the tapered portion adjacent tissue; and, displacing the instrument in a direction parallel to the axis of displacement to contact and cut the tissue with the larger second cutting section of the tapered portion. 
     In a further embodiment of the invention, provided is an improved method of delivering an implant to a selected location in the body. The method comprises the steps of providing an implant assembly consisting of a first component, and a second component removably interfit with the first component; providing a guide member slidably extending through the first and second components to maintain the components as a unitary implant in a selected registration; and, sliding the implant assembly along the guide member to the selected location in the body. 
     In still a further embodiment of the invention, provided is an improved method to deliver an implant to a selected location in the body. The method comprises the steps of providing an implant assembly consisting of a first component, and a second component housed within the first component; providing a guide member slidably extending through the first and second components to maintain the components as a unitary implant in a selected registration; and, sliding the implant assembly along the guide member to the selected location in the body. 
     In yet a further embodiment of the invention, provided is an improved method of altering the orientation of at least one of a pair of vertebra. The method comprises the steps of providing a lever having a distal end and a proximate end; inserting the lever intermediate and contacting the pair of vertebra; and, displacing the lever to displace at least one of the pair of vertebra. 
     In yet still a further embodiment of the invention, provided is an improved method of separating tissue. The method comprises the steps of providing an instrument having a portion with an offset axis of rotation such that a first section of the instrument to one side of the axis of rotation is wider than a second section of the instrument to the other side of the axis of rotation; positioning the instrument with the second section of the instrument in the tissue; and, rotating the instrument about the axis of rotation to separate the tissue. 
     In an additional embodiment of the invention, provided is an improved method of inserting a device intermediate two adjacent vertebra. The method comprises the steps of providing an elongate guide unit; manipulating the guide unit to displace tissue; sliding a device along the guide unit to a position intermediate the vertebra and changing the shape of a disc intermediate the vertebra. 
     In still an additional embodiment of the invention, provided is an improved method of inserting a device intermediate two adjacent vertebra. The method comprises the steps of providing an elongate guide unit; manipulating the guide unit to displace tissue; and, sliding a device along the guide unit to a position intermediate and contacting the vertebra and changing the alignment of the vertebra. 
     In yet an additional embodiment of the invention, provided is an improved method of inserting a device intermediate two adjacent vertebra. The method comprises the steps of providing an articulating implant; inserting the implant intermediate the vertebra; articulating the implant; and, separating the implant into at least two portions. 
     In yet still an additional embodiment of the invention, provided is an improved method to insert a device intermediate two adjacent vertebra. The method comprises the steps of providing an implant having at least two sides and an opening extending through the implant from one of the sides to the other of the sides; and, inserting the implant between the vertebra such that a different one of the sides contacts each of the vertebra independent of the device orientation. 
     In another embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue with an initial shape. The method comprises the steps of detecting a change in the shape of the joint; and, inserting the implant in the joint. 
     In still another embodiment of the invention, provided is an improved method of inserting an implant in a joint having tissue having an initial shape. The method comprises the steps of changing the shape of the joint; detecting the change in shape; and, inserting the implant. 
     In yet another embodiment of the invention, provided is an improved method of inserting an implant in a joint. The method comprises the steps of providing an articulating implant unit having a hinge interconnecting at least a pair of body members; providing a guide unit; inserting the guide unit into the joint; sliding the implant unit along the guide unit and dispensing the implant unit from the guide unit to contact the joint, articulate, and position within the joint; and, detecting the location of one of a group of the body members and the hinge to determine the location of the implant unit in the joint. 
     In yet still another embodiment of the invention, provided is an improved method of conforming an implant to the shape of a joint. The method comprises the steps of providing an articulating implant unit having a hinge interconnecting at least a pair of body members; providing a guide unit; inserting the guide unit into the joint; and, sliding the implant unit along the guide unit and dispensing the implant unit from the guide unit to contact the joint, articulate, and conform to the shape of the joint. 
     In a further embodiment of the invention, provided is an improved method of inserting an implant in a joint. The method comprises the steps of providing an elongate guide unit and implant configured to pass by an existing device adjacent a joint; inserting the guide unit and manipulating the guide unit by the existing device; and, inserting the implant into the joint. 
     In another embodiment of the invention, provided is an improved method of inserting an implant into a disc intermediate two vertebra. The method comprises the steps of providing a guide unit and an implant configured to conform to the shape of said disc; inserting the guide unit adjacent the disc; manipulating the guide unit to conform to the shape of the disc; sliding said implant unit along the guide unit: and, inserting the implant into the disc. 
     In still a further embodiment of the invention, provided is an improved method reforming an implant in a joint. The method includes the steps of providing an implant with at least two articulations; and, sequentially articulating the implant by inserting the implant in the joint. The implant can be implant is inserted in the joint along a guide unit comprising at least one of a group consisting of a wire, a cable, a lever, a driver, and a sleeve. The implant can dampen, fuse, or seal the joint; can conform to the shape of the joint; or, can include a concave side and an axis of rotation at the concave side. 
     In still another embodiment of the invention, provided is a method of inserting a hinge in a joint. The method comprising the steps of providing a hinge with at least one tooth; and, inserting the hinge in the joint such that the tooth fixes the hinge in the joint. 
     In yet still a further embodiment of the invention, provided is an improved method to insert a structure in a joint. The method comprises the step of providing an implant. The implant includes at least a first portion, a second portion, a guide unit, and a vertical hinge joining the first and second portions and contacting the joint. The method also includes the step of dispensing the implant from the guide unit such that the first portion is displaced with respect to the second portion, and the hinge contacts and fixes the implant in the joint. The implant can include a concavity and the hinge can be located at the concavity. The implant can include a convexity and a spring can be located at the convexity. 
     In an alternate embodiment of the invention, provided is a method of reforming an implant in a joint. The method comprises the steps of providing an implant including at least a first portion, a second portion, a spring contacting the first and second portions; and, reforming the implant by inserting the implant at least partially in the joint and reducing the tension in the spring. The implant can be inserted in the joint along a guide unit comprising at least one of a group consisting of a wire, a cable, a lever, a driver, and a sleeve. The implant can dampen the joint, fuse the joint, seal the joint, or conform to the shape of the joint. 
     In another alternate embodiment of the invention, provided is an improved method to insert a structure in a joint. The method comprises the step of providing a guide unit and an implant. The implant includes at least a first portion, a second portion, and a displacement spring contacting the first and second portions. The portions and spring are shaped and dimensioned such that when the implant is dispensed from the guide unit the first portion is displaced with respect to the second portion. The method also comprises the step of displacing the first portion with respect to the second portion by dispensing the implant from the guide unit. The implant can be inserted in the joint along a guide unit comprising at least one of a group consisting of a wire, a cable, a lever, a driver, and a sleeve. The implant can dampen the joint, fuse the joint, seal the joint, conform to the shape of the joint, include a convexity such that the spring is located at the convexity, or include a concavity and a hinge located at the concavity. 
     In a further alternate embodiment of the invention, provided is an improved method to insert an implant in a joint. The method comprises the steps of providing an implant in a first configuration; inserting the implant at least partially in the joint; articulating the implant to a second configuration; fixing the implant in the joint; and, articulating the implant to at least a third configuration. The implant can be inserted in the joint along a guide unit comprising at least one of a group consisting of a wire, a cable, a lever, a driver, and a sleeve. The implant can dampen the joint, fuse the joint, seal the joint, conform to the shape of the joint, include a convexity and a spring located at the convexity, and include a concavity and a hinge located at the concavity. 
     In still another alternate embodiment of the invention, provided is an improved method of inserting a device into a joint. The method comprises the steps of providing an articulating implant compressed into a first linear configuration; inserting the implant at least partially into a joint; and, articulating the implant into at least a second arcuate configuration within the joint. The implant can be inserted in the joint along a guide unit comprising at least one of a group consisting of a wire, a cable, a lever, a driver, and a sleeve. The implant can dampen the joint, fuse the joint, seal the joint, conform to the shape of the joint, include a convexity and a spring is located at the convexity, or include a concavity and a hinge located at the concavity. 
     In still a further alternate embodiment of the invention, provided is an improved method of inserting a device into a joint. The method comprises the steps of providing an articulating implant having a first configuration; inserting the implant at least partially into a joint; and, articulating said implant into a second configuration extending over a surface area larger than the first configuration. The implant can be inserted in the joint along a guide unit comprising at least one of a group consisting of a wire, a cable, a lever, a driver, and a sleeve; can articulate from a first linear configuration to a second arcuate configuration; can dampen, fuse, seal or conform to the shape of the joint; can includes a convexity and a spring located at the convexity; or, can include a concavity and a hinge located at the concavity. 
     In yet still another alternate embodiment of the invention, provided is an improved method to position a structure in a joint. The method comprises the steps of providing an articulating implant in a first closed configuration; inserting the articulating implant at least partially in the joint; and, articulating the implant from the first configuration to a second open configuration. The implant can be inserted in the joint along a guide unit comprising at least one of a group consisting of a wire, a cable, a lever, a driver, and a sleeve; can articulates from a linear configuration to a second arcuate configuration; can dampen, fuse, or seal the joint; can conform to the shape of the joint; can include a convexity and a spring located at the convexity; and, can include a concavity and a hinge located at the concavity. 
     Turning now to the drawings, which depict the presently preferred embodiments of the invention for the purpose of illustrating the practice thereof and not by way of limitation of the scope of the invention, and in which like reference characters refer to corresponding elements throughout the several views,  FIGS. 1 to 5  illustrate a disc revitalization device constructed in accordance with the principles of the invention and generally indicated by reference character  100 . 
     Disc revitalization device  100  includes a housing having an upper generally semi-oval member  42  and a lower generally semi-oval member  41 . Shaft  59  is mounted on and inside the housing. The head  30  of shaft  59  includes an hex opening or indent  31 A shaped to contour to and receive slidably the hexagonally shaped end of an elongate tool used to turn the head  30  of shaft  59 . Unitary master cam  10  is fixedly secured to the center of shaft  59 , along with externally threaded member  57  and externally threaded member  58 . Member  57  is received by an internally threaded aperture in member  42 A. Member  58  is received by an internally threaded aperture in member  43 A. Conical members  42 A and  43 A each have a truncated conical exterior shape and have inner cylindrical openings that can slide along shaft  59  in the directions indicated by arrows B and C, respectively, when members  57 ,  58  rotate and displace members  42 A,  43 A along shaft  59 . Members  57  and  58  are oppositely threaded such that when shaft  59  is turned in the direction of arrow A, member  57  turns inside conical member  42 A and slidably displaces member  42 A along shaft  59  in the direction of arrow B, and, member  58  turns inside conical member  43 A and slidably displaces members  43 A along shaft  59  in the direction of arrow C. 
     When members  42 A and  43 A are slidably displaced along shaft  59  in the direction of arrows B and C, respectively, the outer conical surfaces of members  42 A and  43 A slide over the arcuate inner surface  11 B and  11 C of arcuate shells  11  and  11 A, respectively, and displace shell  11  upwardly away from shaft  59  in the direction of arrows D and E and shell  11 A downwardly away from shaft  59  in directions X and Y opposite the directions indicated by arrows D and E. 
     Teeth or pins  12  depend outwardly from base  12 A ( FIG. 2 ) and are shown in the retracted position in  FIGS. 2 and 4 . Base  12 A is mounted inside shell  11  beneath and within the head  56  of shell  11 . Wave spring  13  contacts an undersurface of head  56  and downwardly displaces base  12 A away from the head  56 . Spring  13  therefore functions to maintain teeth  12  housed and retracted in openings  12 B. Openings  12 B extend through head  56 . When teeth  12  are in the retracted position illustrated in  FIG. 2 , edge  88  of master cam  10  is in the position illustrated in  FIG. 2  such that rib  53  engages slot  80  on the bottom of base  12 A and prevents base  12 A (and shell  11 ) from moving laterally in the directions indicated by arrows J and K in  FIG. 2 . When, however, a hex tool is used to rotate head  30  and shaft  59  in the direction of arrow A, master cam  10  rotates simultaneously with shaft  59  in the direction of arrow M ( FIG. 1 ) until rib  53  turns completely out of slot  80  and smooth cam surface  54  engages and slidably contours to the arcuate bottom  12 C of base  12 A. When surface  54  engages bottom  12 C, surface  54  is flush with adjacent portions of the conical outer surfaces of members  42 A and  43 A such that bottom  12 C of base  12 A and bottom  11 B of shell  11  are free to slide laterally in the directions of arrows B and C over surface  54  and the outer conical surfaces of members  42 A and  43 A, and such that bottom  12 C of base  12 A and bottom  11 B of shell  11  are free to rotate or slide in the direction of arrow M ( FIG. 1 ) and in a direction opposite that of arrow M over surface  54  and the outer conical surfaces of members  42 A and  43 A. This ability of shell  11  and base  12 A to move bidirectionally or multidirectionally (i.e., to move polyaxially) by sliding laterally (in the direction of arrows J and K), by sliding forwardly or rotationally (in the direction of arrow M), and by sliding in direction intermediate said lateral and forward directions facilitates the ability of device  100  to adapt to movement of a vertebra. In addition, as rib  53  is turned out of and exits slot  80 , cam surfaces  81  and  82  contact and slidably displace base  12 A upwardly in the direction of arrow O ( FIG. 2 ) to compress and flatten wave spring  13  and to displace teeth  12  outwardly through openings  12 B such that teeth  12  are in the deployed position illustrated in  FIG. 1 . 
     As can be seen in  FIG. 3 , the construction of shell  11 A and the base, head  56 A, and teeth in shell  11 A is equivalent to that of shell  11 , base  12 A, and teeth  12 . 
     In  FIG. 3 , the end of shaft  59  is slidably received by aperture  52 A formed in member  42 A and interlocks with another portion of shaft  59  (not visible) inside member  42 A. Members  57  and  58  are not, for sake of clarity, illustrated on shaft  59  in  FIG. 3 . 
       FIG. 6  illustrates the insertion of device  100  in a disc  50 . An opening  51  is formed through the annulus  50 A and device  100  is inserted inside the annulus. In  FIG. 6 , the size of the opening  51  is greater than normal and is exaggerated for purposes of illustration. When device  100  is inserted in disc  50 , teeth  12  are retracted ( FIG. 4 ). After device  100  is inserted, the hex end of a tool ( FIG. 1A ) is inserted in and engages opening or indent  31 A and the tool is used to turn shaft in the direction of arrow A to outwardly displace shells  11  and  11 A and to deploy teeth  12  ( FIG. 1 ). 
     Another particular advantage of the invention is that in many cases it is not necessary to make an opening in disc  50  in order to insert device  100 . Device  100  preferably has a shape and dimension that permit insertion through a pre-existing rupture in the annulus of a disc  50 . The device can be inserted through the rupture “as is” (i.e., as the rupture exists), or the rupture can, if necessary, be widened sufficiently to permit insertion of device  100  through the rupture and annulus into the nucleus area circumscribed by the annulus. When a device  100  is inserted through a pre-existing rupture—either by inserting device  100  through the rupture as is or by widening and increasing the size of the rupture—it is not necessary to form another opening in the disc annulus. 
       FIG. 7  illustrates a surgical instrument  61  being utilized to insert disc revitalization device  100  in an intervertebral disc  50  that is adjacent and intermediate an upper vertebra  77 B and a lower vertebra  78 B in the spinal column of an individual  60 . As would be appreciated by those of skill in the art, individual  60  is normally in a prone position when a device  100  is inserted in a disc  50 . 
     One particular advantage of the invention is that in many cases it is not necessary to force apart the vertebra  77 B and  78 B bounding a disc  50  in order to insert device  100 . Device  100  preferably has a shape and dimension that permits an incision to be made in disc  50  (preferably without cutting out a portion of disc  50 ) and the incision to be widened sufficiently to insert device  100  inside the disc  50 . Any desired method can be utilized to insert device  100  in disc  50 . 
     One method for inserting device  100  in the interior of disc  50  is utilized to insert device  100  in the front, back, or one of the side of a disc  50  without separating the pair of vertebra between which disc  50  is sandwiched. This method may include the step of using a needle to palpate and penetrate the annulus to the center of the disc. The stylette is removed from the needle and a guide wire is inserted until the tip of the wire is in the disc. The needle is removed from the guide wire. A dilator is placed on the guide wire and is used to enlarge the opening in the annulus. The wire is removed. A tube is inserted over the dilator. The dilator is removed. The device  100  is inserted through the tube into disc  50 . The tube is removed. Before the tube is removed, an appropriately shaped and dimensioned tool  101  ( FIG. 1A ) can be inserted through the tube to engage and turn head  30  to outwardly displace shells  11  and  11 A and deploy teeth  12 . 
       FIG. 8  illustrates a damaged disk  70  that has developed a convex bulge in portion  74  of the annulus  72 . The bulge generates pressure against the inner portion  75  of the spinal column  71 . The pressure compresses nerves in the spinal column  71 , causing pain. Similar pressure against nerve roots  77  and  78  can be generated when the annulus bulges and/or ruptures and material from the nucleus  73  herniates through the rupture and produces pressure against spinal column  71  or nerve roots  77  and  78 . 
       FIG. 9  illustrates one procedure to relieve the pressure caused by bulge  74 . A disc revitalization device  76  is inserted inside the annulus  72  and generates pressure against the annulus  72  in the direction of arrows S and T that causes the annulus to lengthen in those directions. When the annulus lengthens, the middle portions of the annulus tend to be drawn in the direction of arrows R and Z, narrowing the annulus and displacing the convex bulge away from the portion  75  of the spinal column  71 . The shape and dimension of device  76  can be varied as desired to alter the shape of annulus  72 , nucleus  73 , and disc  70  in any desired manner when device  76  is inserted in disc  70 . While portions of the nucleus  73  and annulus  72  can be removed to insert device  76 , it is preferred that little, if any, of the nucleus  73  and annulus  72  be removed during installation of device  76 . The principal object of the invention is, as much as possible, to revitalize a disc  70  so that the functioning of disc  70  resembles as closely as possible the functioning of a normal healthy disc, or resembles as closely as possible the functioning of disc  70  before it was compressed, widened, bulged, herniated, ruptured, or otherwise damaged. To achieve this object, it normally is desirable to leave in place as much as possible of the original disc material. 
     In  FIG. 9 , portion  74  has taken on a concave orientation. The disc  70  in  FIG. 9  has a so-called “C-shape” generally associated with a normal healthy disc. The C-shape of disc  70  is produced in part because of the concave orientation of portion  74 , which represents the center portion of the C-shape. One drawback of the C-shape of disc  70  is that portions  72 A and  72 B of disc  70  are, as can be seen in  FIG. 9 , adjacent nerve roots  78  and  77 , respectively, which makes it more likely that portions  72 A and  72 B can, by bulging, by herniation of the nucleus through a rupture, by adding materials to the annulus, by inserting devices that widen when compressed, or otherwise, exert undesirable pressure on nerve roots  78  and  77 . The embodiment of the invention illustrated in  FIG. 11  minimizes the likelihood of such an occurrence. 
     In  FIG. 11 , the disk revitalization device  76  is shaped and dimensioned such that when device  76  is inserted in disc  70 , the inner wall  73 A of annulus  72  contacts and conforms to device  76  such that disc  70  no longer has a C-shape, but has an oval shape. The outer arcuate wall  73 D of disc  70  becomes convex along its entire length. The oval shape of disc  70  spaces portions  72 A and  72 B further away from nerve roots  78  and  77  and reduces the likelihood that a bulge or hernia will contact and produce undue pressure on roots  78  and  77 . In the practice of the various embodiments of the invention described herein, it is not required that disc  70  be manipulated by a device  76  or other means to take on an oval shape, and it is not required that the normal C-shape of a disc  70  be dispensed with. It is, however, preferred that disc revitalization device  76  manipulate a disc  70  such that the shape of disc  70  tends to change from the normal C-shape and become more oval, or that at least the section of disc  70  that is adjacent spinal column  71  and nerve roots  78  and  77  and that is comprised of portions  72 A,  74 , and  72 B tend to become more convex and adopt a curvature more comparable to a portion of an oval. 
     It is not believed necessary for a disc revitalization device to contact the inner wall  73 A of the annulus  72  of a disc  70  in order for the device to cause the shape of a disc to change. For example,  FIG. 10  illustrates a disc revitalization device  77 A that is inserted in the nucleus  73  of a disc  70  and that does not contact the inner wall  73 A of the annulus  72 . Device  77 A is shaped such that it tends to force material comprising the nucleus  73  to gather and be compressed in areas  73 F and  73 G. Such a compression of nuclear material can generate forces that act in the direction of arrows U and V and that tend to cause disc  70  to elongate in the directions of arrows U and V. Regardless of whether a device  76 ,  77 A,  100  contacts the inner wall  73 A of the annulus  72  of a disc  70 , it is preferred that all, or substantially all, of the outer surface of the portion of the housing  41 ,  42  that will contact the nucleus  73  or the annulus  72  have a smooth, preferably arcuate, shape about at least one axis. By way of example, and not limitation, the surface of a cylindrical is arcuate about one axis. The surfaces of a sphere or egg are each arcuate about more than one axis. 
     Use of a disc revitalization device  100  is further described with reference to  FIGS. 12 and 13 . In  FIG. 12 , damaged disc  95  has been compressed between vertebra  90  and  91  and is bulging outwardly through and from the bottom  92  of disc  90  and the top  93  of disc  91 . The disc  95  has ruptured at two locations and herniated material  96 ,  97  from the nucleus extends outwardly through the ruptures. In  FIG. 12 , the bulging of disc  95  outside of vertebra  90  and  91  is, for sake of simplicity, pictured as being uniform around the perimeter of the vertebrae. This is not normally the case. The amount that the disc  95  bulges typically varies with the location on the periphery of the bottom  92  of vertebra  90  and top  93  of vertebra  91 . Similarly, the herniation of nucleus material  96 ,  97  is, for sake of simplicity, pictured in a generally uniform spherical shape. This is not normally the case. The shape of a herniation of nucleus material need not be uniform or have the shape and dimension of any recognizable symmetric geometric figure. 
     After device  100  is inserted internally into the nucleus of disc  95 , a tool with a hex end is inserted in opening  31 A and the tool is utilized to turn head  30  in the direction of arrow A ( FIG. 1 ) to displace and expand shell  11  outwardly in the direction of arrows D and E, to displace and expand shell  11 A of  FIG. 2  outwardly in the direction of arrows X and Y and away from shell  11  ( FIG. 1 ), to deploy teeth  12  to engage a portion of the bottom  92  of vertebra  90  ( FIG. 12 ), to deploy teeth associated with shell  11 A to engage a portion of the top  93  of vertebra  91 , and to subject disc  95  to internal traction by displacing vertebra  90  and/or  91  vertically along axis G in a direction generally normal to the bottom  92  of vertebra  90  and to the top  93  of vertebra  91  to increase the separation distance between vertebra  90  and  91 , to increase the height H of disc  95 , and to decrease the width W of disc  95 . Since a spine is generally curved along its length, vertebra in the spine are not stacked one directly on top of the other along a straight vertical axis. One vertebra usually is slightly canted with respect to its adjacent vertebra. Nonetheless, the axis G can be said to be generally normal (with plus or minus 45 degrees) to the bottom  92  of one vertebra and to the top  93  of an adjacent vertebra. 
     When disc  95  is subjected to internal traction, the disc  95  often tends to undergo a transformation from the short, squat, bulged configuration of  FIG. 12  to the tall, retracted configuration illustrated in  FIG. 13 . The bulged part of the disc  95  retracts inwardly to a position between vertebrae  90  and  91  in the same general manner that the bulge  105  in rubber band or string  102  ( FIG. 14 ) retracts inwardly when the ends of the string  102  are pulled in the directions indicated by arrows  103 ,  104  to produce the “taller” (i.e., longer) string  102  illustrated in  FIG. 15 . When bulge  105  retracts inwardly, the width W of the disc  95  is reduced. 
     Further, when disc  95  takes on the tall retracted configuration of  FIG. 13 , the volume of the space inside and circumscribed by the inner edge  73 A ( FIG. 10 ) of the annulus (i.e., the space in which material comprising the nucleus  73  is found) increases because the increase in the height of the space concomitant with the increase in the height of disk  95  usually offsets and is greater than the decrease in the diameter or width of the space concomitant with the retraction of the disk  95 . The increase in the volume of the space in which the nucleus is found generates negative pressure or generates forces that tend to pull or permit the herniated nucleus material  96 ,  97 —that prior to internal traction extended outwardly through ruptures in the annulus  94  in the manner illustrated in FIG.  12 —to move through the associated disc ruptures and back into the inner annular space in which nucleus material is ordinarily found. Increasing the height of and retracting disc  95  also tends to close or partially close ruptures  98  formed in the annulus  94  ( FIG. 13 ) so that the ruptures often will heal completely closed of their own accord. Similarly, if an opening has been made through the annulus  94  to facilitate insertion of a disc revitalization device  100 , the internal traction of disc  95  tends to close the opening to facilitate healing of the opening. Such an incision normally, but not necessarily, would be vertically oriented in the same manner that annulus rupture  98  is vertically oriented in  FIG. 13 . 
     The device  100  can be oversized and shaped such that during internal traction the device  100  prevents the internal opening (which opening would be bounded by the internal wall  73 A of the annulus) in the annulus of disc  95  from completely retracting or reducing in size to a particular width when a disc moves from the bulging configuration of  FIG. 12  to the retracted, taller configuration of  FIG. 13 . When device  100  prevents the internal opening in the annulus from fully inwardly retracting or constricting along axes that lie in a horizontally oriented plane that is generally normal to axis G in  FIG. 13 , the annulus and/or nucleus generate and maintain for at least a while compressive forces against the device  100 . This “tensioning” of the annulus and/or nucleus tends to anchor the device  100  in position in disc  95 , to prevent migration of device  100 , and therefore to produce a unitary, stronger structure comprised of the disc  95  and the “captured” or a “squeezed” device  100 . 
     The shape and dimension and constructions of the disc revitalization device  100  can vary as desired provided that device  100 , when inserted in a disc  95 , can be utilized to separate a pair of adjacent vertebrae  90 ,  91  the distance necessary during internal traction to obtain the desired retraction and height increase of a disc  95  intermediate the pair of vertebrae. It is desirable that device  100  functions to contact the nucleus and/or annulus of the disc  95  to produce the desired shape of disc  95 , and/or that the device  100  functions to contact the nucleus and/or annulus of the disc  95  to produce tension in the annulus and/or nucleus because the device  100  prevents disc  95  from fully retracting and causes the nucleus and/or annulus to squeeze or compress device  100 . 
     In  FIG. 11 , one acceptable contour of the portion of a disc  70  that is closest to nerves  77 ,  78  and spinal column  71  is the oval convex shape indicated by dashed line  200 . A more preferred contour (than the contour indicated by dashed line  200 ) is the relatively flat contour depicted by the flat line representing portion  74  of disc  70 . The most preferred contour is the concave contour represented by dashed line  201 . The contour represented by dashed line  201  is most preferred because it is less likely that any bulge or herniation of disc  70  will press against nerves  77 ,  78  or against spinal column  71 . It is, of course, preferred that each of the contours  200 ,  74 ,  201  of disc  70  be spaced apart from nerves  77 ,  78  and spinal column  71  to minimize the likelihood that a portion of disc  70  will contact nerves  77 ,  78  and spinal column  71 . As used herein in connection with the invention and the claims, a disc includes at least fifty percent (50%) of its original annulus and may or may not include all or a portion of its original nucleus. 
       FIGS. 16 and 17  illustrate a unitary ribbon spring apparatus constructed in accordance with the invention and generally indicated by reference character  110 . Apparatus  110  includes ends  117  and  118 , raised portions or peaks  113  to  115 , and teeth  111 ,  112 ,  116 . 
     In use, apparatus  110  is placed in an intervertebral disc between an opposing pair of vertebrae. Apparatus  110  can circumscribe material in the nucleus of the disc, can circumscribe material in the annulus of the disc, can circumscribe material in the annulus and the nucleus of the disc, or, when the nucleus or a portion of the nucleus has been removed, can circumscribe only a small amount of disc material or circumscribe no disc material at all. When the vertebrae are in their normal relatively uncompressed state (as when an individual is walking slowly, is in a relaxed standing position, or is reclining) apparatus  110  may contact each of the vertebrae pair, may contact only one vertebra, or may “float” in the disc without contacting either of the adjacent vertebrae. When the vertebrae are compressed, the top vertebra presses against and flattens elastic peaks  113  to  115 , on the first surface of apparatus  110 , in a direction toward the bottom vertebra. Flattening peaks  113  to  115  causes apparatus  110  to lengthen inwardly in the manner indicated by arrows  120  and  121 . Apparatus  110  may also roll and slide inwardly over the adjacent vertebrae. If, however, peaks  113  to  115  are sufficiently compressed, teeth  111 ,  112 ,  116 , on the second surface of apparatus  110  fixedly engage the bottom vertebra (or the top vertebra if teeth are provided along the first surface of apparatus  110 ) and prevent further movement of apparatus  110  until the opposing vertebrae separate and the compressive force acting on peaks  113  to  115  is released. When the compressive force is released, apparatus  110  elastically partially or completely returns to the configuration of  FIG. 16 . Teeth  11 ,  112  can completely disengage from the lower (or upper) vertebra. If teeth  111 ,  112 ,  116  remain engaged or partially engaged with the lower (or upper) vertebra, then apparatus  110  may only partially return to its configuration of  FIG. 16 . 
     As noted, flattening peaks  113  to  115  causes ends  117  and  118  to move inwardly in the direction of arrows  120  and  121 , respectively. A section of the disc nucleus or other disc material typically is circumscribed by apparatus  110 . When ends  117  and  118  move inwardly (away from the outer peripheral edge  72 A ( FIG. 21 ) of annulus  72 ) in the direction of arrows  120  and  121  ( FIG. 16 ), ends  117  and  118  tend to gather disc material (nucleus and/or annular material) by compressing a portion of the section of the disc nucleus that is circumscribed by apparatus  110 . In addition, when ends  117  and  118  move inwardly, they tend to gather disc material by drawing inwardly portions of the disc that are not circumscribed by apparatus  110  but that are contacting or near ends  117  and  118 . Gathering disc material and displacing inwardly portions of the disc reduces the horizontal expansion forces  150  to  153  ( FIG. 21 ) acting on the disc. Compressing apparatus  110  acts to horizontally narrow, inwardly contract, or un-bulge the disc in the direction of arrows  140 - 142  to counteract horizontal expansion forces  150  to  153 . When portions of the disc are drawn inwardly, vertical “anti-compression” forces each acting against a vertebra in the direction of arrows  122  and  123  ( FIG. 17 ) are also generated which tend to offset a portion of the compressive forces generated against the disc by the adjacent vertebrae. Vertical anti-compression forces  122  and  123  are generated by apparatus  110  when the disc is compressed between and by its neighboring pair of vertebrae. Vertical anti-compression forces  122 ,  123  tend to increase the height of the disc and further horizontally narrow, inwardly contract or un-bulge, the disc. Vertical anti-compression forces  122 ,  123  are each generally normal to the bottom surface  92  of vertebrae  90  or top surface  93  of vertebra  91  in  FIG. 12 ,  13 . Horizontal inward forces  140 - 143  acting opposite horizontal outward forces  150 - 153  in  FIG. 21  are generally parallel to the bottom surface  92  of vertebra  90  or top surface  93  of vertebra  91  in  FIG. 12 ,  13 . 
       FIG. 18  illustrates insertion apparatus  124  that can be utilized to implant spring apparatus  110  in a disc. Insertion apparatus  124  includes hollow channel  125 . Apparatus  110  is housed in the end of channel  125 . After the distal end  129  of channel  125  is positioned adjacent or in an opening in the annulus  72  in  FIG. 19 , plunger  126  is displaced in the direction of arrow  130  to eject apparatus  110  out of distal end  129  and into the disc to the position illustrated in  FIG. 19 . When apparatus  110  is inserted in a disc  70 , apparatus  110  draws disc material away from the inner part  75  of the spinal column  71  to reduce the pressure generated on nerves in the spinal column  71 . When apparatus  110  is compressed between a pair of vertebrae, ends  117  and  118  in  FIG. 16  or other portions of apparatus  110  draw nuclear material or other disc material away from the inner part  75  of the spinal column  71  to reduce the pressure generated on nerves in the spinal column  71 . ( FIG. 19 ). 
       FIG. 20  illustrates apparatus  110  inserted inside a disc  70  and intermediate vertebrae  127 ,  128 . 
       FIG. 21  illustrates an alternate unitary spring apparatus  130  constructed in accordance with the invention. Apparatus  130 , like apparatus  110 , includes a first surface with peaks  131  to  133 . Peaks  131  to  133  are, as illustrated in  FIGS. 23 and 24 , higher toward the inside of apparatus  130  than toward the outside of apparatus  130 . As will be discussed below, this height or elevation differential causes each peak  131  to  133  to function like a cam when apparatus  130  is compressed between a pair of vertebra ( FIG. 24 ). Apparatus  130  also includes cylindrical, paddle shaped, spaced apart ends  137  and  138  and includes members  134  to  136 . Each member  134  to  136  includes a semi-cylindrical bottom second surface that rolls and slides over the vertebra contacted by the semi-cylindrical bottom surface. 
     When apparatus  130  is compressed by vertical forces  147  to  149  generated by a vertebra contacting peaks  131  to  133 , peaks  131  to  133  cant inwardly away from the outer circumference or peripheral edge of the annulus  72 A in the directions indicated by arrows  140  to  142 . This inward canting causes the semi-cylindrical bottom surfaces of members  134  to  136  to roll, and/or slide, inwardly in the manner indicated by arrows  145  and  146 . Ends  137  and  138  are also caused to roll, and/or slide, inwardly in the manner indicated by arrows  143  and  144 . When a vertebra contacts peaks  131  to  133 , the vertebra, in addition to causing the peaks to roll inwardly, also flattens the peaks  131  to  133  to cause a lengthening of apparatus  130  akin to the lengthening produced in apparatus  110  in  FIG. 16  when the peaks of apparatus  110  are flattened; and, to cause an inward displacement of ends  137 ,  138  ( FIG. 21 ) akin to the inward displacement of ends  117  and  118  in the direction of arrows  120  and  121  ( FIG. 17 ). When apparatus  110  is utilized, teeth  111 ,  112  on the apparatus dig into a vertebra each time the apparatus  110  is compressed. Consequently, the teeth may damage the vertebra. Apparatus  130  does not have such teeth. Apparatus  130  only slides or rolls over the surface of a vertebra. In this respect, apparatus  130  is sometimes preferred over apparatus  110 . The inward displacement of ends  137 ,  138  gathers up and compresses some of the disc material (i.e., nuclear and/or annular material) that is circumscribed and enclosed by apparatus  130  and/or that is adjacent ends  137 ,  138 . Such gathering of disc material produces two additional results. 
     First, vertical anti-compression forces  154  and  155  ( FIG. 21 ) are generated which offset to some extent the compression forces generated against the annulus  72  and nucleus of the disc. Forces  154  and  155  are generally perpendicular to the top  93  and bottom  92  of the vertebrae adjacent the disc. ( FIG. 12 ). 
     Second, the portion of disc material gathered up and compressed by apparatus  130  is elastic. The gathered up disc material produces its own outwardly acting return forces  156 ,  157  that act on ends  143  and  144  and other portions of apparatus  130  and assist in returning spring apparatus  130  to its original configuration when the vertebrae adjacent the disc separate toward their normal relatively uncompressed configuration and release the compressive forces acting on apparatus  130 . Similar return forces are generated by compressed elastic disc material and act on apparatus  110  when apparatus  110  is compressed and gathers in elastic disc material. (FIG.  16 , 17 ). 
     The spring apparatus  160  illustrated in  FIG. 22  is similar to apparatus  130  ( FIG. 21 ), except that semi-cylindrical members  134  to  136  of apparatus  130  comprise—in apparatus  160 —cylindrically shaped members  134 A to  136 A. Peaks  131 A to  133 A are equivalent to peaks  131  to  133  of apparatus  130 . Ends  137 A and  138 A of apparatus  160  are equivalent to ends  137  and  138  of apparatus  130 . Ends  137 A and  138 A can, if desired, be interconnected by a member  161 . The shape and dimension and construction of a spring apparatus utilized in the practice of the invention can vary as desired. 
     The functioning of spring apparatus  130  is further illustrated in  FIGS. 23 and 24 . In  FIGS. 23 and 24 , the disc that is normally between vertebrae  90 A and  91 A is omitted for sake of clarity. Apparatus  130  would ordinarily preferably be implanted inside the disc between vertebrae  90 A and  91 A.  FIG. 23  illustrates a portion of apparatus  130  prior to the vertebrae being compressed together. In  FIG. 24 , the vertebrae  90 A and  91 A have been compressed together and force  148  is acting on the various peaks of apparatus  130 , including the specific peak  131  shown in  FIG. 23 . Tip  131 B of peak  131  is higher than the remainder of the peak and functions as a cam. When bottom of vertebra  92 A presses downwardly in the direction of force  148  against tip  131 B ( FIG. 24 ), peak  131  is displaced and cants inwardly in the direction indicated by arrow  161 , causing the semi-cylindrical bottom surface of member  130  to tilt and/or slid on the top  93 A of vertebra  91 A in the direction of arrow  162 . The inward canting and rolling or sliding of portions of spring apparatus  130  functions to gather in and compress nuclear and/or annular disc material that is circumscribed by apparatus  130 . After the vertebra  90 A and  91 A separate and the compressive force  148  is released, apparatus  130  elastically returns to its normal orientation illustrated in  FIG. 23  and peak  131  and member  136  return to the orientation illustrated in  FIG. 23 . 
     Another spring apparatus  165  of the invention is illustrated in  FIGS. 25 to 27  and includes four mini-towers  166  to  169 . The towers  166  to  169  are interconnected by flexible strips  174  to  177 . The construction of each tower  166  to  169  is identical. Tower  166  is illustrated in  FIGS. 26 and 27 . Tower  166  include cylindrical plunger  180  slidably received by hollow cylindrical base  182 . Plunger  180  rests on spring  183  mounted in base  182 . When a compressive force  181  is applied to plunger  180 , spring  183  is downwardly deflected and flattened, pushing cupped member  170  away from base  182  and inwardly away from the outer peripheral edge  72 A ( FIG. 21 ) of the disc in which apparatus  165  ( FIG. 25 ) is implanted. Consequently, when the apparatus  165  is implanted in an intervertebral disc and bottom  92 A of a vertebrae ( FIG. 24 ) compresses plunger  180  ( FIG. 27 ), members  170  to  173  ( FIG. 25 ) are inwardly moved and function to gather up and compress disc material that is within and circumscribed by apparatus  165 . 
     A constant tension coil-ribbon spring  185  is illustrated in  FIG. 28  and includes end  186  and coil  187 . 
     The intervertebral disc is, for sake of clarity, omitted from  FIG. 29 . End  186  of spring  185  is fixedly secured in an opening  188  formed in vertebra  90 A. Coil  187  is positioned intermediate vertebrae  90 A and  91 A. When vertebrae  90 A and  91 A move toward one another a compressive force  189  is generated. Force  189  compresses the disc intermediate the vertebrae, and compress coil  187  that winds or coils more tightly in direction  190  and tends to draw inwardly into coil  187  adjacent disc material. When the compressive force  189  is released, coil  187  elastically unwinds to return to its normal uncompressed state. 
       FIGS. 30 ,  31 ,  30 A, and  31 A illustrate another embodiment of the invention in which a spring apparatus  191  ( FIG. 30A ) is provided that has the same general shape and dimension as apparatus  110  ( FIG. 16 ), except that the peak portions  113 ,  114 ,  115  are replaced by portions  192  that bow inwardly when the apparatus  191  ( FIG. 30A ) is compressed in the direction of  194  ( FIG. 30 ,  31 ).  FIGS. 30 and 30A  illustrate apparatus  191  in its normal “at rest” state.  FIGS. 31 and 31A  illustrate apparatus  191  when it is under compression and portions  192  have elastically bowed portion  193  inwardly to gather in and compress disc material circumscribed by apparatus  191 . 
     An apparatus  100  ( FIG. 1 ),  76  ( FIG. 9 ),  77 A ( FIG. 10 ),  110  ( FIG. 16 ),  130  ( FIG. 21 ),  160  ( FIG. 22 ),  165  ( FIG. 25 ),  185  ( FIG. 28 ), and  191  ( FIG. 30A ) can be inserted in a disc in one, two, or more separate pieces that are not interconnected and may independently function in the disc. The spring apparatus and other apparatus described herein may be utilized in other body in joints and locations other than within intervertebral discs and between vertebrae in the spine. The intervertebral disc is an example of a soft tissue compartment adjoining first and second bones (vertebra) having an initial height and an initial width. Other joints consisting of a soft tissue compartment adjoining at least first and second bones having an initial (vertical) height and an initial (horizontal) width may include the joints of the hand, wrist, elbow, shoulder, foot, ankle, knee, and hip. 
     The materials utilized to construct a apparatus  100  ( FIG. 1 ),  76  ( FIG. 9 ),  77 A ( FIG. 10 ),  110  ( FIG. 16 ),  130  ( FIG. 21 ),  160  ( FIG. 22 ),  165  ( FIG. 25 ),  185  ( FIG. 28 ), and  191  ( FIG. 30A ) can vary as desired. Metals and metal alloys are presently preferred. 
     One method for constructing a spring apparatus  110  is illustrated in  FIGS. 32 and 33 . The first step of the process is to feed a metal ribbon through stepper collet jaws to articulate twists incrementally at a 90 degree orientation with respect to each other to produce the articulated ribbon  200 . In the second step, the articulated ribbon  200  is formed in matching dies to produce vertical bends or peaks in horizontal flat portions of the ribbon. This result is the articulated “peaked” ribbon  201  shown in  FIG. 32 . The third step of the process is to grind or otherwise form teeth in the vertically oriented sections of the ribbon to produce the articulated “peaked” toothed ribbon  202  shown in  FIG. 32 . The fourth and final step of the process is to roll the ribbon  202  to produce the annular ring shape of apparatus  110  ( FIG. 33 ). 
     Anatomical planes are drawn through an upright body. These planes include the coronal plane, the sagittal plane, and the axial plane.  FIG. 34  illustrates the general relationship of anatomical planes with vertebrae  90 B,  91 B and disc  70 A in the spinal column. The coronal, or frontal, plane  210  is a vertically oriented plane that is generally parallel to the front of an individual&#39;s body. The sagittal plane  211  is a vertically oriented plane that is normal to the coronal plane and that is parallel to the sides of an individual&#39;s body. The transverse, or axial, plane  212  is a horizontally oriented plane that passes through the waist of an individual&#39;s body and that is normal to the coronal and sagittal planes. 
     The spine has normal curvatures which are either kyphotic or lordotic. 
     Scoliosis is a deformity of the spinal column in which the spinal column is curved from its normal upright orientation laterally in the coronal plane in the direction of arrow  218  or of arrow  217 . 
     Lordosis is a deformity of the spinal column in which the spinal column is curved from its normal upright orientation rearwardly in the sagittal plane in the direction of arrow  216 . In contrast to the normal curvatures of the spine, lordosis produces an excessive inward curvature of the spine. 
     Kyphosis is a deformity of the spinal column in which the spinal column is curved from its normal upright orientation forwardly in the sagittal plane in the direction of arrow  215 . 
     Scoliosis, lordosis, and kyphosis can be accompanied by a rotation  214  of the spine about a vertically oriented axis  213 , and can also be accompanied by undesirable movement of the ribs and or pelvis. 
     For example, scoliosis often is characterized by both lateral curvature and vertebral rotation. As scoliosis advances, vertebrae spinous processes in the region of the major curve rotate toward the concavity of the curve. The ribs move close together towards the pelvis on the concave side of the curve. The ribs are widely spaced apart on the convex side of the curve. Continued rotation of the vertebral bodies is accompanied by increases deviation of the spinous processes to the concave side. The ribs follow the rotation of the vertebrae. On the convex side, the ribs move posteriorly and produce a rib hump commonly associated with thoracic scoliosis. On the concave side, the ribs are pushed anteriorly and deform the chest. 
     Lordosis can occur simultaneously with scoliosis, as can kyphosis. 
     Any of the apparatus previously described herein can, when appropriate and desirable, be utilized in the processes described below in conjunction with  FIGS. 35 to 40  to treat deformities of the spinal column. 
     In  FIG. 35 , cylindrical apparatus  230  is inserted between a pair  228 ,  229  of canted, spaced apart panel members. When a downward displacement force  231 A is applied to panel  228 , panel member  228  pivots about apparatus  230  in the same manner that a door rotates about its hinge. Panel member  228  moves about apparatus  230  in a single rotational direction indicated by arrow  232  such that the outer edge  246  of panel member  228  moves toward panel member  229 . Likewise, a displacement force  231 B acting against panel member  229  can cause panel member  229  to pivot about apparatus  230  in a single rotational direction indicate by arrow  233 . Arrows  232  and  233  each lie in a common plane. 
     As is illustrated in  FIG. 36 , cylindrical apparatus  230  can be utilized to treat adjacent vertebrae that are misaligned or misrotated due to scoliosis, lordosis, kyphosis, or other causes. In  FIG. 36  vertebra  90 B is canted from its normal orientation with respect to vertebra  91 B. In its normal orientation, the bottom  90 C of vertebra  90 B would be generally parallel to the top  90 D of vertebra  91 B. Elongate cylindrical apparatus  230  is positioned intermediate vertebrae  90 B,  91 B adjacent opposing edge portions  220 ,  221  of vertebrae  90 B,  91 B, respectively, on the “concave” side of the misalignment. Edge portions  222 ,  223  of vertebrae  90 B,  91 B, respectively, are on the “convex” side of the misalignment of the vertebrae. Apparatus  230  may be (1) constructed in any desired manner, and (2) positioned between vertebrae  90 B,  91 B in any desired manner and at any desired location therebetween as long as apparatus  230  functions to improve the alignment of vertebrae  90 B,  91 B such that bottom  90 C is more nearly parallel to top  90 D and/or such that at least one of vertebrae  90 B,  91 B is rotated about a vertical axis  213  in  FIG. 34 , to more closely approach its natural position or to more closely approach another desired position and orientation. By way of example, and not limitation, when apparatus  230  is inserted it may (1) only contact top  90 D and may or may not be secured to top  90 D, (2) be secured to and only contact bottom  90 C, (3) be positioned further away from edge portions  220 ,  221  and nearer the center of bottom  90 C and top  90 D, (4) comprise a spring that is “loaded” and generates a force  224  that (like force  231  in  FIG. 35 ) acts upwardly against bottom  90 C until edge portions  220  and  221  are a selected distance apart, or (5) comprise, in contrast to the spring just mentioned, a solid non-elastic member that functions only as a pivot point like the hinge of a door. 
     In  FIG. 37 , conical apparatus  234  is inserted between a pair  228 ,  229  of canted, spaced apart panel members. When a downward displacement force  231 A is applied to panel member  228 , panel member  228  pivots about apparatus  234  in the same manner that a door rotates about its hinge. Since, however, there is a space between panel member  228  and the tapered end  239  of apparatus  234 , panel member  228  also pivots about the larger end of member  234  such that end  228 A moves downwardly toward end  239  in the manner indicated by arrow  237 . Consequently, when apparatus  234  is inserted and force  231 A is applied to panel member  228 , panel member  228  moves about apparatus  234  in at least a pair of rotational directions indicated by arrows  232  and  237 . Likewise, a displacement force  231 B acting against panel member  229  can cause panel member  229  to pivot about apparatus  230  in at least a pair of rotational directions. 
     As is illustrated in  FIG. 38 , conical apparatus  234  can be utilized to treat adjacent vertebrae that are misaligned or misrotated due to scoliosis, lordosis, kyphosis, or other causes. In  FIG. 38  vertebra  90 B is canted from its normal orientation with respect to vertebra  91 B. In its normal orientation, the bottom  90 C of vertebra  90 B would be generally parallel to the top  90 D of vertebra  91 B. Elongate conical apparatus  234  is positioned intermediate vertebrae  90 B,  91 B adjacent opposing edge portions  220 ,  221  of vertebrae  90 B,  91 B, respectively, on the “concave” side of the misalignment. Edge portions  222 ,  223  of vertebrae  90 B,  91 B, respectively, are on the “convex” side of the misalignment of the vertebrae. Apparatus  234  may be (1) constructed in any desired manner, and (2) positioned between vertebrae  90 B,  91 B in any desired manner and at any desired location therebetween as long as apparatus  234  functions to improve the alignment of vertebrae  90 B,  91 B such that bottom  90 C is more nearly parallel to top  90 D and/or such that at least one of vertebrae  90 B,  91 B is rotated about a vertical axis  213  in  FIG. 34 , to more closely approach its natural position or to more closely approach another desired position and orientation. By way of example, and not limitation, when apparatus  234  is inserted it may (1) only contact top  90 D and may or may not be secured to top  90 D, (2) be secured to and only contact bottom  90 C, (3) be positioned further away from edge portions  220 ,  221  and nearer the center of bottom  90 C and top  90 D, (4) comprise a spring that is “loaded” and generates a force  224  that acts upwardly against bottom  90 C until edge portions  220  and  221  are a selected distance apart, or (5) comprise, in contrast to the spring just mentioned, a solid non-elastic member that functions only as a pivot point like the hinge of a door. 
     In  FIG. 39 , tapered arcuate apparatus  245  is inserted between a pair  228 ,  229  of canted, spaced apart panel members. When a downward displacement force  231 A is applied to panel member  228 , panel member  228  pivots about apparatus  245  in the same manner that a door rotates about its hinge. Since, however, there is a space between panel member  228  and the tapered end  240  of apparatus  245 , panel member  228  also pivots about the larger end of member  245  such that end  228 A moves downwardly toward panel member  229  in the manner indicated by arrow  237 . Further, arcuate apparatus  245  is shaped to cause panel member  228  to rotate in the direction indicated by arrow  244  about a vertical axis  243 . Consequently, when apparatus  245  is inserted and force  231 A is applied to panel member  228 , panel member  228  moves about apparatus  245  in at least a pair of rotational directions indicated by arrows  232  and  237 , as well as in a rotational direction indicated by arrow  244 . 
     As is illustrated in  FIG. 40 , tapered arcuate apparatus  245  can be utilized to treat adjacent vertebrae that are misaligned or misrotated due to scoliosis, lordosis, kyphosis, or other causes. In  FIG. 40  vertebra  90 B is canted from its normal orientation with respect to vertebra  91 B. In its normal orientation, the bottom  90 C of vertebra  90 B would be generally parallel to the top  90 D of vertebra  91 B. Tapered arcuate apparatus  245  is positioned intermediate vertebrae  90 B,  91 B adjacent opposing edge portions  220 ,  221  of vertebrae  90 B,  91 B, respectively, on the “concave” side of the misalignment. Edge portions  222 ,  223  of vertebrae  90 B,  91 B, respectively, are on the “convex” side of the misalignment of the vertebrae. Apparatus  245  may be (1) constructed in any desired manner, and (2) positioned between vertebrae  90 B,  91 B in any desired manner and at any desired location therebetween as long as apparatus  245  functions to improve the alignment of vertebrae  90 B,  91 B such that bottom  90 C is more nearly parallel to top  90 D and/or such that at least one of vertebrae  90 B,  91 B is rotated about a vertical axis  213  in  FIG. 34 , to more closely approach its natural position or to more closely approach another desired position and orientation. By way of example, and not limitation, when apparatus  245  is inserted it may (1) only contact top  90 D and may or may not be secured to top  90 D, (2) be secured to and only contact bottom  90 C, (3) be positioned further away from edge portions  220 ,  221  and nearer the center of bottom  90 C and top  90 D, (4) comprise a spring that is “loaded” and generates a force  224  that acts upwardly against bottom  90 C until edge portions  220  and  221  are a selected distance apart, or (5) comprise, in contrast to the spring just mentioned, a solid non-elastic member that functions only as a pivot point like the hinge of a door. 
     An apparatus  230 ,  234 ,  245  typically generates a force  224  acting on a vertebra  90 B in at least one of two ways. If the apparatus  230 ,  234 ,  245  is elastic or non-elastic and is forced between portions  220  and  221 , the apparatus  230 ,  234 ,  245  at the time it is inserted produces an upwardly directed force  224  that acts to move portion  220  upwardly and therefore tends to cause portion  222  to pivot in the direction of arrow  226 . Or, if the apparatus  230 ,  234 ,  245  is elastic or non-elastic and is not forced between portions  220  and  221 , then when an individual&#39;s spine is compressed, either artificially or during normal movement of the individual, and a downward compressive force  235  is generated on vertebra  90 B to press vertebra  90 B against apparatus  230 ,  234 ,  245 , then when portion  220  is pressed against apparatus  230 ,  234 ,  245 , apparatus  230 ,  234 ,  245  produces a counteracting upwardly acting force  224  that, along with force  235 , functions to cause vertebra  90 B to pivot and/or rotate about apparatus  230 ,  234 ,  245  such that portion  222  pivots in the direction of arrow  226 , or such that vertebra  90 B rotates in a direction  241  about a vertical axis  242  ( FIG. 40 ). 
     In  FIGS. 36 ,  38 ,  40 , the intervertebral disc has been omitted for sake of clarity. Although apparatus  230 ,  234 ,  245  can be utilized when the intervertebral disc is not present, it is presently preferred in the spirit of the invention that most or all of intervertebral disc be present and that apparatus  230 ,  234 ,  245  be inserted within the annulus of the disc and between vertebrae  90 B,  91 B. Consequently, while apparatus  230 ,  234 ,  245  functions to correct deformities in the spine, apparatus  230 ,  234 ,  235  also functions to improve the functioning and shape of discs intermediate spinal vertebrae. 
     As noted, an intervertebral disc interconnects vertebra bones in a spinal column. The disc includes an annulus and a nucleus. As used herein, the annulus is a hard tissue compartment that houses soft tissue comprising the nucleus. Other hard tissue found in the body includes bone, cartilage, and the capsules located at the end of bones at the joints of the hand, wrist, elbow, shoulder, foot, ankle, knee, and hip. Soft tissue in the body includes epithelium, fascia, muscle, fat, vasculature, and nerves. 
     Vasculature and nerves of differing width, or diameter, exist throughout the body. The larger vasculature and nerves are deemed principal vasculature and nerves. The lesser vasculature and nerves are deemed minor vasculature and nerves. As used herein, principal vasculature and nerves have a width of at least one millimeter (mm). 
     An object of many surgical procedures is to produce an opening in an intervertebral disc or other hard tissue including cartilage, bone, and the capsules around joints. During these surgical procedures, the distal end of an instrument often is passed through soft tissue in order to reach the hard tissue in which the opening is to be formed. Since the distal end of the instrument often has a sharp tip or cutting edge that is used to form an opening in the hard tissue, there is a significant risk that the distal end will cut or pierce principal vasculature or nerves and produce a serious injury, possibly a life threatening injury. 
       FIG. 41  illustrates a portion  310  of a spinal column, including vertebrae  314 ,  315 ,  315 A, and intervertebral discs  311 ,  312 ,  313 . Principal nerves  316 ,  317 ,  318  emerge from the spinal column. Arrow  319  illustrates a preferred path for an instrument to travel in order to avoid nerves  316  and  317  and to impinge on the annulus  313 A of disc  313 . Path  319  may not, however, avoid impingement on a nerve  316 ,  317  in the event a nerve  316  happens to be in an unusual position, in the event disc  313  is squeezed into an bulging configuration that causes vertebrae  315  and  315 A and nerves  316  and  317  to move closer together, etc. 
       FIGS. 42 ,  44 ,  45  illustrate apparatus  321  constructed in accordance with the invention and including a distal end  322  and handle  323 . During insertion in the body of a patient, apparatus  321  is manually or mechanically oscillated back and forth in the direction of arrows  3 A, oscillated up and down in the direction of arrows  3 B and  3 C, oscillated laterally in the direction of arrows  3 E and  3 D ( FIG. 43 ), oscillated in a manner that combines movement in two or more of said directions  3 A to  3 E, i.e., the distal end  322  can be moved along an elliptical or circular path, oscillated radially in and out in the manner of fingers  365 ,  366 ,  368 , and  369  in  FIG. 47D , and/or oscillated rotationally about the longitudinal axis of the apparatus in the manner indicated by arrows  3 P in  FIG. 47C . Since the purpose of moving end  322  is to produce an opening in and through tissue, the in-and-out oscillating movement indicated by arrows  3 A ( FIG. 42 ) is preferred and typically is required even if oscillating movement of end  322  in the direction of arrows  3 B and  3 C, in the direction of arrows  3 E and  3 D ( FIG. 43 ), along a circular path, radially, or rotationally is also employed. The frequency and amplitude of oscillation can vary as desired, as can the force or pressure applied to handle  323  to press end  322  into tissue  332 ,  333  toward selected hard tissue  330  ( FIG. 44 ). When passing end  322  through soft tissue, particularly soft tissue where there is no principal vasculature or nerves. A longer amplitude and smaller frequency is typically employed. When passing end  322  through hard tissue, a higher frequency and smaller amplitude typically is preferred. By way of example, and not limitation, the frequency of radial, linear, or rotational oscillation through soft tissue or hard tissue is greater than or equal to 0.1 cycles per minute. The amplitude of oscillation can vary as desired, but the amplitude of oscillation typically is greater in soft tissue than it is in hard tissue. 
     Apart from forward movement of a distal end  322 ,  322 B to  322 E ( FIGS. 47 ,  48 ,  49 ,  47 B,  47 C) caused by oscillation, forward movement of a distal end  322  through soft tissue in a direction L ( FIG. 47 ) can vary as desired, but typically is greater in soft tissue than it is in hard tissue. 
     The pressure required for a rounded distal end  322 ,  322 B to  322 E to tear or pierce or otherwise injure a principal nerve or vasculature varies depending on the shape of the tip of the end  322 ,  322 B to  322 E and on the size and makeup of the nerve or vasculature, but is readily determined by experimentation so that a surgeon can avoid applying pressure in the direction of travel L ( FIG. 47 ), having a magnitude sufficient to injure a principal nerve or vasculature. 
       FIG. 44  illustrates the location of instrument  321  and distal end  322  after end  322  has been oscillated to pass through epithelium  332 , through other soft tissue including fat, facia, muscle, minor vasculature and nerves, and principal vasculature and nerves, and through the annulus  330  of disc  313  into the nucleus  331 . Since the epithelium  332  can be difficult to penetrate initially, a small incision can be made in epithelium  332  to facilitate the passage of end  322  therethrough. 
     The shape of end  322  is important. Various shapes of end  322  are illustrated in  FIGS. 46 to 49 , and in  FIGS. 47B ,  47 C,  47 D and  47 E. 
     The distal end  322 A in  FIG. 46  has a sharp tip, or point,  332 . Distal end  322 A is not utilized in the practice of the invention because tip  332  can readily puncture or cut a principal nerve  33  or vasculature. Similarly, a distal end that includes a cutting edge is not preferred in the practice of the invention. 
     The distal end  322 B illustrated in  FIG. 47  has a rounded tip  334  and is a preferred construct in the practice of the invention. If tip  334  contacts a principal nerve  333  while moving and/or oscillating in the direction of arrow  3 L, it is likely that nerve  333  will slide off to one of the sides indicated by arrows  3 F and  3 G. If, on the other hand, tip  334  contacts nerve  333  “dead on” and nerve  333  impedes the progress of tip  334  in the direction of arrow  3 L, the surgeon that is manually oscillating instrument  321  will feel the resistance (or a sensor on a machine that is oscillating instrument  321  will detect the resistance) and can laterally displace tip  334  in the direction of arrow N or M to facilitate the movement of nerve  333  in the direction of arrow  3 G or F over end  334  so that tip  334  can continue moving in the direction of arrow  3 L. The surgeon increases the certainty that tip  334  has contacted principal nerve  333  or principal vasculature by determining the location of tip  34  with a fluoroscope, with an endoscope, by direct visualization, by patient feed back, by an electrical recording of a nerve, by an alteration of blood pressure or pulse rate caused by contacting a blood vessel, or any other desired means. 
     The distal end  322 C illustrated in  FIG. 48  has a rounded tip  335  and is also a preferred construct in the practice of the invention. If tip  335  contacts a principal nerve  333  or vasculature while moving and/or oscillating in a direction toward nerve  33 , it is likely that nerve  333  will slide off to one of the sides of end  322 C indicated by arrows H and I. If, on the other hand, tip  335  contacts nerve  333  “dead on” and nerve  333  impedes the progress of tip  35 , the surgeon that is manually oscillating instrument  321  (or a sensor on a machine that is oscillating instrument  321 ) will detect the resistance and can manipulate the handle  323  of instrument  321  ( FIG. 44 ) to laterally displace tip  335  to facilitate the movement of nerve  333  in the direction of arrow  3 H or  3 I over end  335  so that tip  335  can continue moving past nerve  333 . The surgeon increases the certainty that tip  335  has contacted principal nerve  333  or principal vasculature by determining the location in the patient&#39;s body of tip  335  with a fluoroscope, with an endoscope, by direct visualization, by patient feed back, by an electrical recording of a nerve, by an alteration of blood pressure or pulse rate caused by contacting a blood vessel, or any other desired means. Once the surgeon determines the location of tip  335 , the surgeon&#39;s knowledge of the normal anatomy of an individual and/or knowledge of the patient&#39;s particular anatomy assists the surgeon in determining if a principal nerve or vasculature has been contacted by tip  335 . 
     The distal end  322 D illustrated in  FIG. 49  has a rounded tips  336 ,  338  and detent  337  and is also a preferred construct in the practice of the invention. If tip  336  or  338  contacts a principal nerve  333  while moving and/or oscillating in a direction toward nerve  333 , it is likely that nerve  333  will slide off to one of the sides of end  322 D in a direction indicated by arrow  3 K or  3 J. If, on the other hand, detent  337  contacts nerve  333  “dead on” and nerve  333  seats in detent  337  and impedes the progress of end  322 D, the surgeon that is manually oscillating instrument  321  will feel the resistance (or a sensor on a machine that is oscillating instrument  321  will detect the resistance) and can manipulate the handle  323  of instrument  321  ( FIG. 44 ) to laterally displace distal end  322 D to facilitate the movement of nerve  333  in the direction of arrow  3 J or  3 K over end  322 D so that end  322 D can continue moving past nerve  333 . The surgeon increases the certainty that end  322 D has contacted principal nerve  333  or principal vasculature by determining the location in the patient&#39;s body of tips  336 ,  338  with a fluoroscope, with an endoscope, by direct visualization, by patient feed back, by an electrical recording of a nerve, by an alteration of blood pressure or pulse rate caused by contacting a blood vessel, or any other desired means. Once the surgeon determines the location of tips  336 ,  338 , the surgeon&#39;s knowledge of the normal anatomy of a the body of a human being or animal and/or knowledge of the patient&#39;s particular anatomy, assists the surgeon in determining if a principal nerve or vasculature has been contacted by end  322 D. 
     The spoon-shaped distal end  322 E illustrated in  FIG. 47B  has a curved paddle surface  356  and a rounded edge  357  and is also a preferred construct in the practice of the invention. If rounded edge  357  contacts a principal nerve  333  while moving and/or oscillating in a direction toward nerve  333 , it is likely that nerve  333  will slide off to one of the sides of end  322 E. It is preferred that edge  357  contact nerve  333  (or principal vasculature) in the manner illustrated in  FIG. 47B  with surface  356  generally parallel to the longitudinal axis  333 A of the nerve. If, on the other hand, edge  357  contacts nerve  333  in an orientation in which the spoon surface  356  of  FIG. 47B  is rotated ninety degrees such that surface  536  is generally normal to axis  333 A, there is a greater risk of injury to nerve  333 . If edge  357  contacts nerve  333  “dead on” such that nerve  333  impedes the progress of end  322 E in the direction of arrow  3 X, the surgeon that is manually oscillating instrument  321  ( FIG. 44 ) will feel the resistance (or a sensor on a machine that is oscillating instrument  321  will detect the resistance) and can manipulate the handle  323  of instrument  321  ( FIG. 44 ) to laterally displace distal end  322 E ( FIG. 47B ) to facilitate the movement of nerve  333  laterally from edge  357  so that end  322 E can continue moving past nerve  333 . The surgeon increases his certainty that edge  357  has contacted principal nerve  333  or principal vasculature by determining the location in the patient&#39;s body of edge  357  with a fluoroscope, with an endoscope, by direct visualization, by patient feed back, by an electrical recording of a nerve, by an alteration of blood pressure or pulse rate caused by contacting a blood vessel, or any other desired means. Once the surgeon determines the location of edge  357 , the surgeon&#39;s knowledge of the normal anatomy of a the body of a human being or animal and/or knowledge of the patient&#39;s particular anatomy assists the surgeon in determining if a principal nerve or vasculature has been contacted by end  22 E. 
     The distal end  322 F illustrated in  FIG. 47D  includes a plurality of curved fingers  365 ,  366 ,  368 , and  369  depicted in their deployed, open position. The fingers are shown in  FIG. 47E  in their normal stowed position adjacent and in opening  367  formed in distal end  322 F of instrument  360 . In the stowed position, a substantial portion of fingers  365 ,  366 ,  368 , and  369  is drawn through opening  367  to a position inside hollow cylindrical body  364 . In the stowed position, however, the curved distal ends of fingers  365 ,  366 ,  368 , and  369  extend outwardly from opening  367  in the manner illustrated in  FIG. 47D  and generally collectively form an arcuate surface similar to the surface on the end of an egg. Moving end  361  in the direction of arrow  3 V ( FIG. 47E ) causes neck  362  to slide into hollow cylindrical body  364  to displace fingers  365 ,  366 ,  368 , and  369  outwardly in the direction of arrow  3 W. When fingers  365 ,  366 ,  368 , and  369  are outwardly displaced in the direction of arrow  3 W, they open radially in the directions indicated by arrows  3 S,  3 Q,  3 R, and  3 T, respectively, to the expanded deployed position illustrated in  FIG. 47D  When end  361  is released, it moves in a direction opposite that of arrow  3 V and returns to the position illustrated in  FIG. 47E , and, similarly, fingers  365 ,  366 ,  368 , and  369  move back to the stowed position illustrated in  FIG. 47E . Consequently, repeatedly manually (or mechanically) pressing end  361  in the direction of arrow  3 V and then releasing end  361  causes fingers  365 ,  366 ,  368 , and  369  to oscillate radially in and out in the directions indicated by arrows  3 Q to  3 T, and causes fingers  365 ,  366 ,  368 , and  369  to oscillate back and forth in the direction of arrow  3 W and in a direction opposite that of arrow  3 W. Rotating distal end  322 E in  FIG. 47C  back and forth in the directions indicated by arrows  3 P causes end  322 E to oscillate back and forth. Continuously rotating end  322 E also, practically speaking, causes end  322 E to oscillate because of the flat spoon shape of end  322 E. 
       FIG. 50  further illustrates the insertion of instrument  340  along wire  324  through epithelium  332  and other soft tissue  333  toward the annulus  326  of disc  325 . 
       FIG. 51  also illustrates instrument  340  slidably mounted on wire  324 . 
       FIG. 52  illustrates an instrument  350  that is utilized to insert an implant  352  in the nucleus  327  of an intervertebral disc  326  ( FIG. 43 ) or to insert the implant  352  in another location in a body. The rounded tip of the implant  352  functions in a manner equivalent to the rounded tips of distal ends  322 B ( FIG. 47 ),  322 C ( FIG. 48 ),  322 D ( FIG. 49 ),  322 E ( FIGS. 47B and 47C ), and  322 F ( FIG. 47D ) to facilitate the passage through tissue of the tip of implant  352 . An implant  380  ( FIG. 51 ) can have a rounded tip like implant  352 , can function in a manner equivalent to the rounded tips of distal ends  322 B,  322 C, etc., and can also have an opening formed therethrough that permits implant  380  to slide or otherwise move along a wire  324  or other elongate member. The shape and dimension of the opening formed through implant  380  can vary as desired, as can the shape and dimension of the elongate member. If an opening of sufficient size exists in tissue and if wire  324  is appropriately oriented, implant  380  may slide along wire  324  of its own accord under the force of gravity to a desired location in a patient&#39;s body. Or, a surgeon&#39;s hand or hands or an auxiliary instrument  350  ( FIG. 52 ) can be utilized to contact and move implant  380  along wire  324  ( FIG. 51 ) to a desired location. As utilized herein, a distal end  322 B,  322 C,  322 D, etc. can comprise an instrument that oscillates or otherwise moves through tissue, as can an implant  380 . The combination of an auxiliary instrument  350  ( FIG. 52 ) with a distal end  322 B,  322 C,  322 D, etc. or implant  380  can also comprise an instrument as long as the combination functions in accordance with at least one of the principles of the invention and separates tissue, forms an opening in tissue, passes through tissue, and/or delivers an implant to a selected location in a patient&#39;s body. Grasping handle  351  and depressing member  353  releases implant  352  from instrument  350 . 
     Forming an opening in tissue with a distal end  322  ( FIG. 44 ) shaped and dimensioned in accordance with the invention requires the end  322  to produce radial forces that work to form an opening in tissue. The tapered configuration of the tips of distal ends  322 ,  322 B to  322 F facilitate the generation of such outwardly acting radial forces. The outward movement of fingers  365 ,  366 ,  368 ,  369  when moving from their stowed to their deployed position generates such radial forces. Rotating or oscillating distal end  322 E ( FIG. 47C ) in the manner indicated by arrows  3 P also generates such “opening widening” radial forces. An opening is formed either by widening an existing opening or by forming a opening in tissue at a location at which no opening previously existed. 
     In one method utilized in the practice of the invention, an implant is utilized to alter the alignment of one or more vertebra, typically to adjust for misalignment of the spine. 
     The first step in this method is to determine how a patient&#39;s spine is misaligned. This is done by taking one or more X-ray pictures of the spine to determine if the spine or a portion of the spine is abnormally tilted or bent toward the front of the patient, is abnormally tilted or bent toward the back of the patient, is abnormally tilted or bent toward one side of the patient, is rotated from its normal position about the vertical axis of the spine, and/or is laterally (horizontally) displaced from its normal position. 
     When the spine is misaligned, the apex constitutes the vertebra(s) or disc that is rotated and/or laterally displaced, but that is least tilted from its normal position. In  FIG. 53 , vertebrae  401 ,  402  of spine  400  comprise the apex because both vertebrae generally are not tilted even though they have been laterally displaced in the direction of arrow  4 A. In  FIG. 54 , vertebra  403  of spine  404  comprises the apex because vertebra generally is not tilted even though it has been laterally displaced in the direction of arrow  4 B. 
     Lateral displacement of a disc  313  or vertebra  315 A is indicated by arrow  315 B in  FIGS. 41 ,  44  and  45 . Rotations of a disc  313  or vertebra about the longitudinal axis of a spine is indicated by arrow  315 C in  FIG. 44 . Tilting of a disc  313  or vertebra  315 A in one particular direction is indicated in  FIGS. 41 and 45  by arrow  315 D. A disc or vertebra can, of course, tilt in a variety of directions away from its normal desired orientation in the spine of a patient. In  FIG. 53 , vertebrae  405  and  406  are tilted away from their normal desired orientation, as is vertebra  407  and disc  408  in  FIG. 54 . 
     The vertebra at the apex or immediately adjacent an intervertebral disc comprising the apex is identified. While an implant can be inserted at any desired location along a patient&#39;s spine, in the embodiment of the invention currently under discussion, an implant is inserted in the spine in a location that is adjacent the end of the vertebra that is at or closest to the apex. It is preferred, although not require, that the implant be inserted within an intervertebral disc or portion of an intervertebral disc that is adjacent the end of the vertebra that is at or closest to the apex. 
     The shape of the implant and the particular location on the end of the vertebra is determined after the particular misalignment of the spine is determined. For example, if the vertebrae between which the implant is to be positioned are tilted with respect to one another such that the disc is compressed in one area and is taller in another area (i.e., the disc is compressed into a wedge shape), it often is desirable to position the implant between the adjacent pair of vertebra near the point of compression of the vertebrae such that the vertebrae will tend to rotate about the implant so that the distance between the vertebrae increases at the point of closest approach of the vertebrae and such that the distance between the vertebrae decreases at the point at which the vertebrae are spaced furthest apart. If the desired rotation of the vertebrae about the implant is similar to the movement of a door about its hinges, then the implant may have a substantially cylindrical shape. 
     If, on the other hand, the adjacent vertebrae are not tilted with respect to one another, but are rotated (about the longitudinal axis of the spine), then the implant may have a tapered or other shape that will produce rotation of one vertebrae with respect to another. 
     It is possible that an implant can be shaped and dimensioned to produce multiple movements of a pair of adjacent vertebrae; for example, to produce simultaneously both rotation of one or more vertebra (i.e., rotation about the longitudinal axis of the spine) and hinge-like pivoting (i.e., pivoting about a horizontally oriented axis that is normal to the longitudinal axis of the spine). 
     In some cases, it may be desirable to utilize first an implant that produces only lateral displacement (or rotation or hinge-like pivoting) and, after the necessary movement of a vertebra(s) has occurred, to remove the implant and insert another implant that will produce hinge-like pivoting (or lateral displacement or rotation). This permits spines that are misaligned in two or more ways to be correct one step at a time. 
     One preferred method of inserting an implant is, as earlier noted, to slide the implant along a guide wire to a desired location in an intervertebral disc and between a selected pair of vertebrae. The guide wire can be inserted utilizing a needle or any other desired apparatus or procedure such that the distal end of the wire is at the desired location in a patient&#39;s body. Typically, the distal end of the guide wire will be located inside an intervertebral disc at the location at which it is desired to deliver an implant. 
       FIGS. 55 and 56  illustrate an intervertebral implant  410  constructed in accordance with the invention and including vertebrae engaging teeth  411  and  412 . U-shaped member  413  includes legs  414  and  415 . As will be appreciated by those of skill in the art, the intervertebral implants illustrated herein may, if desired, be utilized at other locations in a patient&#39;s body. 
       FIGS. 57 to 61  illustrate an intervertebral implant  415  including upper portion  416  and lower portion  417 . Pin  422  of portion  416  pivots in portion  417  and permits portion  416  to rock back and forth in the manner indicated by arrows  4 C and  4 D in  FIG. 58 . Portion  416  includes tissue engaging teeth  418 . Portion  417  includes tissue engaging teeth  419 . 
       FIGS. 62 to 68  illustrate an intervertebral implant  425  including upper portion  426  and lower portion  427 . Portion  426  includes spaced—apart tissue engaging circular ridges  428 . Portion  427  includes tissue engaging teeth  429 . 
       FIGS. 69 to 72  illustrate a unitary implant  435  including inset channels  436 ,  437  formed to increase in width beneath outer surface  438  such that channels  436 ,  437  interlock bone or other material that is placed, packed or grows into channels  436 ,  437  and solidifies. The intervertebral implants illustrated herein can be formed from any desired material, but presently preferably comprise stainless steel, titanium alloys, polymers, composites, ceramics, bone, or another material. 
       FIGS. 73 to 76  illustrate a unitary cylindrically shaped implant  440  with an aperture  441  formed therethrough and with tissue engaging circular ridges  442 . When desired, implant  440  can be utilized as a fusion device by packing aperture  441  with bone or other material that will fixedly engage and fix in place an opposing pair of vertebrae. The cylindrical shape of implant  440  facilitates implant  440  being utilized as a hinge between a pair of opposing vertebrae to cause the vertebrae to pivot about implant  440  to an alignment in which the spacing between the vertebrae is more uniform at all points. Apertures  440 A and  440 B permit a guide wire to be slidably inserted longitudinally through implant  440 . 
       FIGS. 77 to 80  illustrate a unitary implant  450  with an aperture  451  formed therethrough and with tissue engaging circular ridges  452 . When desired, implant  450  can be utilized as a fusion device by packing aperture  451  with bone or other material that will fixedly engage and fix in place an opposing pair of vertebrae. Apertures  450 A and  450 B permit a guide wire to be slidably inserted longitudinally through implant  440 . Apertures  460 A and  460 B can be internally threaded to permit a tool to be removably turned into the apertures to facilitate insertion of implant  450 . 
     Implant  440  ( FIGS. 72 to 76 ) and implant  450  ( FIGS. 77 to 80 ) can have tissue engaging ridges along their entire length. 
       FIGS. 81 to 85  illustrate a unitary implant  460  with tissue engaging teeth  461  and  462 . 
       FIGS. 86 and 87  illustrate a unitary implant  470  similar to implant  460 , but with a reduced height. 
       FIGS. 88 and 89  illustrate a unitary implant  471  similar to implant  460 , but with a further reduced height. 
       FIG. 90  is an exploded view of an implant  480  similar to implant  410  ( FIGS. 55 ,  56 ) including members  481  and  482  that pivot about cylindrical pin  483  when member  482  is inserted intermediate upstanding arms  486  and  487 , when pin  483  is inserted through apertures  484 ,  489 , and  485 , and, when member  481  is fixedly attached to member  482 . Member  482 A is a bearing with a spherically shaped convex outer surface or edge  497 . Hollow cylindrical sleeve  496  includes an inner concave surface that glides over surface  497  such that sleeve  496  can tilt forwardly, rearwardly, and, as indicated by arrows  498 , laterally on bearing  482 A. Sleeve  496  can also rotate over surface  497  and around pin  483 . Member  481  is fixedly mounted to sleeve  496  and moves about bearing  482 A simultaneously with sleeve  496 . When implant  480  is being inserted between a pair of vertebrae with a tool  488 , the end  489  of tool  488  is preferably shaped to slide intermediate arms  486  and  487  in the direction of arrow  4 R such that lower edge  481 A bears against upper surface  489 A and prevents member  481 , and therefore sleeve  496  from moving. Edge  490  bearing against the lower outer surface  491  contributes to stabilizing implant  480 . After implant  480  is inserted between a pair of vertebra, tool  488  is removed in a direction opposite that of arrow  4 R. Tool  488  can take on any shape and dimension as long as tool  488  prevents, at least in part, implant  480  (or any desired component(s) of an implant) from moving while the implant is being inserted at a desired location in a patient&#39;s body. 
       FIGS. 91 and 92  illustrate a unitary implant  492 . 
       FIGS. 93 and 94  illustrate a unitary implant  500 . 
       FIGS. 95 to 99  illustrate a portion  501  of an articulated implant. 
       FIGS. 100 to 102  illustrate a unitary cylindrical, ridged, implant  510  which can have tissue engaging ridges along the entire length of implant  510  and can be rotated or screwed into position as can implants  440  and  450  ( FIGS. 73 to 80 ). 
       FIGS. 103 and 104  illustrate a unitary stepped implant  520 . 
       FIGS. 105 to 109  illustrate a unitary implant  530 . 
       FIGS. 110 to 112  illustrate an articulated implant  540  including portions  501  ( FIGS. 95-99 ) and  502  hinged together by pin  503 . Pin  503  is offset, or positioned, such when implant  540  is in the aligned orientation illustrated in  FIG. 111  and is pushed in the direction indicated by arrow  5 A in  FIG. 110 , portion  501  pivots about pin  503  in the direction indicated by arrow  5 B. This enables implant  540  to follow a curved path of travel. When implant  540  is inserted to a desired location intermediate a pair of vertebrae, it presently preferably travels along a guide wire to said desired location. Cylindrical apertures  503  and  504  formed through portions  502  and  501 , respectively, slidably receive and slide along the guide wire. Apertures  503  and  504  also function to maintain implant  540  in the general alignment illustrated in  FIG. 111  while implant  540  slides along the guide wire. Once, however, implant  540  exits the distal end of the guide wire, utilizing any method or instrument to push implant  540  in the direction indicated by arrow  5 A causes portion  501  to pivot in the direction of arrow  5 B such that implant  540  can move a curved path of travel. This often is desirable when it is desired to move implant  540  along a curved path of travel intermediate a pair of adjacent and opposing vertebrae. 
       FIGS. 113 to 116  illustrate a unitary implant  550 . 
       FIGS. 117 to 120  illustrate a unitary implant  560 . 
       FIGS. 121 to 124  illustrate a unitary implant  570 . 
       FIGS. 125 to 129  illustrate a unitary implant  580  with an aperture  581  formed therethrough to slidably receive a guide wire. 
       FIG. 130  is an exploded perspective view of the implant of  FIGS. 57 to 61 . 
       FIGS. 131 to 136  further illustrate a component  416  of the implant of  FIG. 130 , including a cylindrical aperture  416 A formed therethrough. The aperture can, as indicated by aperture  416 B in  FIG. 136 , be oval shaped (along with pin  422  in  FIG. 148 ) to prevent component  416  from rotating on pin  422 . 
       FIGS. 137 to 140  further illustrate a component  421  of the implant of  FIG. 130 , including apertures  420  and  421 A formed therein. Aperture  420  slidably receives the distal end  420 A of a tool  420 B ( FIG. 149 ). End  420 A bears against or otherwise engages pin  422  to stabilize the implant and prevent the components from tilting or otherwise moving while the implant is inserted. Once the implant is inserted, end  420 A is removed and the implant components and pin are free to cant, tilt, or move as designed. 
       FIGS. 142 to 145  further illustrate a component  417  of the implant of  FIG. 130  and of the implant  415  ( FIGS. 57 ,  60 ,  61 ), including aperture  417 A formed therethrough and including socket  417 C ( FIG. 141 ) shaped to receive foot  424  of pin  422  ( FIG. 130 ). 
       FIGS. 146 to 148  further illustrate the pin  422  and foot  424  utilized in the implant of  FIG. 130 . 
       FIG. 149  further illustrates the implant of  FIG. 130  assembled. Member  421  rocks back and forth in the manner indicated by arrows  4 E on the peaked surface  417 S of member  417 . Member  416  rocks back and forth in the manner indicated by arrows  4 C and  4 D on the peaked surface  421 S of member  421 . Member  416  rocks in directions transverse the directions in which member  421  rocks. Members  416  and  421  can also rock in directions intermediate arrows  4 C,  4 D, and  4 E. Pin  422  can be sized to be slightly smaller in diameter than the apertures  417 A,  421 A, and  416 A ( FIG. 130 ) so that there is slack or “play” and pin  422  can tilt short distances in apertures  417 A,  421 A, and  416 A in directions  4 F,  4 G,  4 H, and  41  ( FIG. 149 ), allowing member  421  to slide over peaked surface  417 S and allowing member  416  to slide over peaked surface  421 S. One advantage of the implant of  FIG. 149  is that it can be constructed to minimize or prevent rotation in the directions indicated by arrows  4 T and  4 U about pin  422  by utilizing peaked surfaces  417 S and  421 S. Another way this can be accomplished is by utilizing, as earlier noted, an oval pin  422  and aperture  416 B ( FIG. 136 ) that is shaped to receive the oval pin (or oval portion of the pin  422 ). Any other desired construction can be utilized to achieve such a limitation of rotation while still permitting members  416  and  421  and pin  422  to tilt or slide in any various desired directions  4 C,  4 D,  4 E,  4 F to  41 , etc. Limiting rotation of an implant helps minimize wear of and facilitates protection of the spine, especially the facet joints  310 Z ( FIG. 41 ). 
       FIGS. 150 to 160  illustrate an alternate implant  600  including a base  601  with apertures  605  to  608  ( FIGS. 157 ,  159 ), including a rocker member  602  with aperture  604  ( FIG. 153 ), and including a pin  603  that extends through apertures  605 ,  604 , and  606  to permit member  602  to pivot on pin  603  in the manner indicated by arrows  6 A ( FIG. 150 ). Pin  603  can be sized slightly smaller in diameter than aperture  604  so that there is slack or “play” and rocker member  602  can move in the direction of arrows  6 B,  6 C or in any desired direction ( FIG. 151 ). Pin  603  can also be attached to a bearing  482 A ( FIG. 90 ) fixed within rocker member  602  to allow motion in the direction of and intermediate to the directions indicated by arrows  6 A,  6 B, and  6 B. Opening  607  in base  601  ( FIG. 157 ) is constructed to minimize or prevent rotation of rocker member  602  in the directions indicated by arrows  6 C ( FIG. 151 ). Any other desired construction can be utilized to achieve such a limitation of rotation while still permitting member  602  and pin  603  to tilt or slide in any various desired direction. Limiting rotation of an implant helps minimize wear of and facilitates protection of the spine. 
       FIGS. 161 to 163  illustrate an implant  620  similar to implant  600 . Implant  620  includes a base  601 A and a rocker member  602 A pivotally mounted in based  601 A on a pin  621 . 
       FIG. 164  illustrates an implant  630  includes an upper shell that can tilt or cant in directions indicated by arrows  7 B,  7 C,  7 D, or in directions intermediate arrows  7 B,  7 C and  7 D. The “football” shape is desirable for insertion into an intervertebral disc because, among other things, it can help minimize invasive surgical procedures. 
     When an implant is inserted by sliding or moving the implant through a hollow guide member, the guide member can be shaped and dimensioned (for example, the guide member can be shaped to have a square inner opening and the outer surface of the implant can have an orthogonal shape) to engage the implant to prevent the implant from rotating in the guide member while the implant in inserted through the guide member. A guide member can detachably engage an implant by turning or threading into an opening formed in the implant, or by any other desired means or construct. 
     Forming openings on implants that expand in size as the opening moves away from the outer surface of the implant is preferred because such openings are believed to tend to draw viscoelastic cartilage, bone, disc nucleus, disc annulus tissue and other material into such openings and to permit the tissue or other material to expand, creep, or otherwise move into the openings such that the material tends to interlock with the openings. Tissue ordinarily moves into openings  655 A,  655  ( FIG. 168 ) because the tissue is continuously or intermittently compressed against an implant and is caused to creep or flow into the openings. Tissue can also be scraped into an opening  655 A,  655  when an implant moves transversely over tissue and a tooth edge or other portion of the implant moves transversely over tissue surface and causes tissue from the surface to move into the opening. Such “scraping” can sometimes occur simultaneously with the implant being compressed against the tissue, which facilitates the ability of a tooth edge or other portion of an implant to scrape tissue into an opening. 
       FIGS. 165 to 170  illustrate an intervertebral implant  650  utilized to translate laterally a vertebra, or possibly an intervertebral disc, with respect to an adjacent vertebra. The individual components of implant  650  are most readily apparent in  FIG. 170 , and include a base  652 , a translation member  651  shaped to slide over base  652 , and a rotatable screw member  653  for laterally displacing member  651  in the direction of arrow  6 R ( FIG. 171 ). Internally threaded nut  661  is mounted orthogonal opening  658  formed in base  652 . Hexagonal opening  654  is formed in the head of member  653 . Leg  662  extends through opening  660 , through opening  658 , through opening  657  in foot  656 , and into aperture  659 . Openings  659 ,  657 , and  660  are not internally threaded. A metal ring (not shown) extends around leg  662  inside opening  658  and adjacent opening  660  to secure leg  662  and maintain leg  662  inside opening  658  when member  653  is turned in the direction of arrow  6 N ( FIG. 170 ). A portion of leg  662  is externally threaded such that turning the head of member  653  in the direction of arrow  6 N with an Allen wrench inserted in opening  654  (or by any other desired means) causes internally threaded nut  661  to move along externally threaded member  662  in the direction of arrow  6 T such that nut  661  bears against foot  656  and displaces foot  656  and translation member  651  in the direction of arrow  6 R ( FIG. 171 ). The presently preferred “starting position” of member  651  is illustrated in  FIG. 171 , although, as would be appreciate by those of skill in the art, the “starting position” of member  651  can correspond to the position illustrated in  FIG. 165  and member  651  can be moved from the position of  FIG. 165  to the position shown in  FIG. 171 . When, however, member  651  is displaced from the beginning position illustrated in  FIG. 171  in the direction of arrow  6 R, member  651  functions to displace simultaneously in the direction of arrow  6 R a vertebra V 1  that is contacted and engaged by member  651 . While vertebra V 1  is transversely or laterally displaced in the direction of arrow  6 R, the adjacent vertebra V 2  contacted and engaged by base  652  can remain substantially fixed, or, vertebra V 2  can be transversely displaced in the direction of arrow  6 M while vertebra V 1  moves in the direction of arrow  6 R, or, vertebra V 1  can remain substantially stationary and not move in the direction of arrow  6 R while vertebra V 2  moves and is transversely displaced in the direction of arrow  6 M. 
     Implant  650 , as do various other implants illustrated in the drawings herein, includes teeth which function to engage vertebra surfaces contacted by the implant. These teeth are typically illustrated herein with interlocking openings  655 A ( FIG. 168 ) formed therebetween that have an arcuate cross-section profile. The width of these interlocking openings increases in at least one direction or dimension as the distance from the outer surface(s) of the implant  650  increases. The shape and dimension of such interlocking openings can vary as desired and can, for example, have a trapezoidal  655  cross-sectional profile instead of an arcuate profile. The width of openings  655 A,  655  need not increase in one or more dimensions as the distance traveled into the openings increases. The width can actually instead remain constant or can actually decrease. It is, as noted, preferred that the width increase so that the openings tend to interlock with tissue that enters and expands into the openings. 
       FIGS. 172 to 177  illustrate an intervertebral implant  670  utilized to translate laterally a vertebra, or possibly an intervertebral disc, with respect to an adjacent vertebra. The individual components of implant  670  are most readily apparent in  FIG. 172 , and include a base  672 , a translation member  671  shaped to move pivotally and transversely with respect to base  672 , and a rotatable screw member  677  for actuating member  671  to move in the direction of arrow  6 U ( FIG. 177 ) when member  677  is turned in the direction of arrow  6 V ( FIG. 177 ) by an Allen wrench inserted in hexagonally shaped socket  678  ( FIG. 174 ). Member  671  includes platform  673  with a plurality of tissue engaging teeth formed thereon. The upper end of leg member  674  is pivotally connected to platform  673  by pin  675  ( FIGS. 172 ,  177 ). The lower end of leg member  674  is pivotally connected to base  672  by pin  679  ( FIGS. 172 ,  177 ). Member  677  includes an externally threaded leg similar to leg  662  of implant  650  ( FIG. 170 ). The externally threaded leg of member  677  extends into an opening formed in T-shaped member  676  such that turning member  677  in the direction of  6 V when implant  670  is in the starting orientation illustrated in  FIG. 177  displaces member  676  laterally in the direction of arrow  6 P ( FIG. 177 ). When member  676  moves laterally or transversely in the direction of arrow  6 P, member  676  bears against and displaces leg  674  in the direction of arrow  6 P such that leg  674  and platform  673  upwardly pivot in the direction of arrow  6 U ( FIG. 177 ). 
     When platform  673  is displaced from the beginning position illustrated in  FIG. 177  in the upward arcuate direction of travel indicated by arrow  6 U ( FIG. 177 ), platform  673  functions to displace upwardly and laterally in the direction of arrow  6 U a vertebra V 3  that is contacted and engaged by member platform  673 . While vertebra V 3  is upwardly and laterally displaced in the direction of arrow  6 U, the adjacent vertebra V 4  contacted and engaged by base  672  can remain substantially fixed, or, vertebra V 4  can be transversely displaced in the direction of arrow  6 W while vertebra V 3  moves in the direction of arrow  6 U, or, vertebra V 3  can remain substantially stationary and not move in the direction of arrow  6 U while vertebra V 4  moves and is transversely displaced in the direction of arrow  6 W. How implant  670  transversely moves vertebrae V 3  and V 4 —and how implant  650  transversely moves vertebrae V 1  and V 2 —depends on a number of factors including the configuration of the patient&#39;s spine, the position of the patient, the position of the implant intermediate the adjacent pair of vertebrae, etc. 
     When member  676  displaces arms  674  in the direction of arrow  6 P, arms  674  continue to pivot about pin  679  until arms  674  nest in and are stopped by U-shaped opening  680  formed in base  672  ( FIGS. 172 ,  173 ,  177 ). Platform  673  or vertebra V 3  can, if desired, pivot in the directions indicated by arrows  7 R ( FIG. 172 ) on pin  675  when platform  673  is in the fully displaced position illustrated in  FIG. 172 . 
       FIGS. 178 and 179  illustrate an instrument constructed in accordance with the invention and generally indicated by reference character  760 . The distal end  722 F includes a rounded tip  765  shaped to be oscillated in and out in directions parallel to the longitudinal axis of instrument  760  in order to facilitate the passage of tip  765  through tissue. Tip  765  includes slot  767  formed therein. Hollow tubular member  764  houses cylindrical member  762  such that member  762  can slide back and forth in member  764 . The distal end (not visible) of cylindrical member  762  is provided with a blade  768  ( FIG. 179 ). Blade  768  includes cutting edge  769 . In  FIG. 178 , blade  768  is in a stowed position inside the distal end  722 F of member  764  and is not visible. In  FIG. 179 , member  762  and blade  768  have been displaced in the direction of arrow  7 W and blade  768  has slid through opening  767  to a deployed position shown in  FIG. 179 . The shape and dimension of blade  768  and tip  765  can vary as desired. Blade  768  and member  762  are moved between the stowed position of  FIG. 178  and the deployed position of  FIG. 179  by displacing end  761  in the direction of arrow  7 V (to move blade  768  from the stowed to the deployed position) and in a direction opposite that of arrow  7 V (to move blade  768  from the deployed to the stowed position). In one mode of operation of instrument  760 , tip  765  is, with blade  768  stowed, oscillated back and forth in directions parallel to arrow  7 V in order to pass tip  765  through tissue to a desired location in an individual&#39;s body. Once tip  765  is at the desired location, end  761  is displaced to form an incision in tissue adjacent tip  765 . To form an incision, blade  768  can be displaced in the direction of arrow  7 W into tissue while member  764  is held in fixed position. Or, after blade  768  is deployed, member  764  and blade  768  can be moved simultaneously to form an incision in tissue. Instrument  760  can be used to make an incision in any tissue in the body such as skin, blood vessels, nerves, organs, joints, etc. One advantage of instrument  760  is that blade  768  can be safely passed among people when blade  768  is in the stowed position and also when not in use. 
     In the event hollow member  764  is intended to house an implant that slides through member  764  to a desired location in an individual&#39;s body, the inner channel in member  764  and opening  767  through which the implant slides can have an orthogonal or other shape or configuration (as can the implant) that engages the implant and prevents the implant from rotating inside member  764  about the longitudinal axis of member  764 . In this fashion, the physician utilizing member  764  can more readily determine the orientation of the implant once the implant exits the distal end of member  764  into a patient&#39;s body. If the member  764  is not rotated (about the longitudinal axis of member  764 ) while the implant is being inserted in a patient&#39;s body, then the orientation of the implant therein remains the same (i.e., the implant does not rotate inside member  764  about the longitudinal axis of member  764 ) while the implant slides therethrough. 
     Similarly, if an implant has an opening formed therethrough that permits the implant to slide down the outside of member  764 , of a wire, etc., the opening formed through the implant and/or the shape and dimension of the outside of member  764  or the wire prevent the implant from rotating about the longitudinal axis of member  764  or of the wire while the implant slides therealong. This enables a surgeon to more readily ascertain the orientation of the implant once the implant passes into a patient&#39;s body. If either member  764  or the wire is not rotated while the implant is being inserted into a patient&#39;s body, then the orientation of the implant thereon remains the same while the implant slides therealong. 
     The position of member  764  or of an implant may also be verified by direct visualization, arthroscope, endoscope, any illuminated light source, fluoroscope, x-ray, camera, video recording, patient feedback, electrical stimulation, ultrasound, or any other desired means. 
       FIGS. 69 to 72  illustrate an implant  435  provided with openings  436 ,  437  having a width that initially expands as the distance from the outer surface of the implant increases. As is illustrated in  FIG. 71 , these openings can be packed or filled with a composition that forms a tooth  700  that engages or penetrates tissue. The composition of tooth  700  can vary as desired. Tooth  700  need not be, but is preferably substantially rigid. Tooth  700  can be porous to facilitate the ingrowth of tissue from a patient&#39;s body and/or resorb over time. In one application, tooth  700  is formed from bone, in which case tooth  700  may fuse with similar tissue in a patient&#39;s body. 
     Another tooth  701  illustrated in  FIG. 71  and includes an outwardly extending tip that functions to penetrate and interlock with tissue in a patient&#39;s body. If tissue in a patient&#39;s body is pressed against the tip of tooth  701 , or vice-versa, the tissue may flow or move around and envelop the tip of tooth  701 . 
     Tooth  700 ,  701  can comprise an integral part of an implant and need not consist of a separate composition that is added to the implant. For example, implant  435  can be cut from a block of stainless steel or any other desired material and include the outwardly extending part of tooth  701 , in which case opening  437  would not exist. 
     The shape and dimension of teeth  700  and  701  can vary as desired. In one embodiment of the invention, an implant includes one or more teeth  700 ,  701  shaped like the keel of a boat. 
     To facilitate inserting implant  435 , openings  436 ,  437  can be filled with a composition that remains flush, extends outward from, or is partially recessed from the outer surface of implant  435 . At least partially filling openings  436 ,  437  may prevent implant  435  from “hooking” or catching on tissue when implant  435  is inserted. Openings  436 ,  437  can be filled with cement or other bonding materials that are press fit or injected from within or around implant  435 . 
     As would be appreciated by those of skill in the art, the various implants described herein can be inserted in any desired joint in a patient&#39;s body or at any other desired location in a patient&#39;s body, including but not limited to a patient&#39;s jaw in connection with the insertion of dental implants or other dental work. Other such joints, by way of example and not limitation, include facet joints, intervertebral discs, and interspinous process joints in the spine. 
     The floating implant  770  of  FIG. 180  includes a flat, football-shaped platform  771  that tends to float on tissue and to ameliorate subsidence of the implant in the tissue. Teeth  772  extend outwardly from platform  771 . Openings  773  are formed intermediate adjacent teeth  772 . The width of an opening  773  initially increases as the distance into the opening  773  increases and the distance away from outer surface(s)  774  increases. I.e., opening  773  initially expands as the distance into opening  773  and away from surface  774  increases. Platform  771  can have any shape or dimension and may be “bean” or “C” shaped to contour to vertebral bones. Platform  771  may be configured to resist subsidence in tissue after removal of a prior implant and/or tissue. Floating implant  770  can be used in revision surgery or to fill substantial defects within the spine. Teeth  772  can be configured as an arcuate concave surface above and below platform  771  to conform to adjacent vertebra. Teeth  772  can have any shape or dimension. 
       FIG. 184  illustrates an orthogonal implant system in which a wire  780  is first inserted in a direction indicated by arrow  7 P into a body to position end  780 A at a selected location in or at a joint or at another location in the body. After end  780 A is positioned at the selected location, dilator  781  is slid over wire  780  in the manner indicated by arrow  7 Q. Elongate, longitudinal, cylindrical channel  782  formed through dilator  781  slides over wire  780 . Tip  781 A of dilator  781  is used to form or expand the size of an opening in the body. Tip  780 A,  781 A can be orthogonal, round or any shape or dimension. Wire  780  or dilator  781  can be used to manipulate and position tissue such as a displaced intervertebral disc and/or misaligned vertebra. Cannula  783  is slid over dilator  781  in the manner indicated by arrow  7 R until edge  785  is at a desired location adjacent or in the opening formed by dilator  781 . Hollow, orthogonal channel  784  in cannula  783  is concentric to and slides over the orthogonal outer surface of dilator  781 . Driver  786  is slide over dilator  781  until end  788  contacts end  789  of cannula  783 . Hollow, orthogonal channel  787  in driver  786  is concentric to and slides over the orthogonal outer surface of dilator  781 . A hammer or other instrument is used to strike cap  790  in the direction of arrow  7 T to drive cannula  783  to a desired location. Driver  786  is removed from dilator  781 . Dilator  781  is removed. Wire  780  can also, if desired, be removed or can remain in cannula  783 . An implant is inserted in end  789  and slid through channel  784  and out the lower end of channel  784  into the body. If wire  780  is left in cannula  783 , the implant can, as previously shown, include an opening formed therethrough that permits the implant to slide down wire  780 . Alternatively, the cannula  783  is removed, and the implant is slide down wire  780 . When an implant is slid through channel  784 , the implant is preferably shaped and dimensioned such that is cannot rotate about the longitudinal axis of cannula  783  (or rotate about a wire  780 ) while sliding through channel  784 . In  FIG. 184 , the longitudinal axis of cannula  783  is parallel to and coincident with arrow  7 S. The combined lengths of driver  786  and cannula  783  exceed the length of wire  780  or dilator  781  so that striking cap  790  does not function to contact end  780 B or end of dialtor  781  and drive wire  780  into the body. 
     The orientation of an implant inserted into the body using the implant system in  FIG. 184  need not be restricted to prevent rotation. For example, a threaded cylindrical implant may be rotated within the implant system in  FIG. 184  to facilitate insertion within the body. The instruments and implant described herein—including but not limited to instrument  760  ( FIG. 178 ), the implant system in  FIG. 184 , implant  435  in  FIGS. 69-72 , and/or implant  770  in FIGS.  180  to  183 —can be transparent, semi-transparent, or opaque to control the amount of light, x-ray, ultrasound, current, etc. used to determine the position of the instrument and/or implant. 
     An alternate construction of dispensing end  322 F of instrument  360  ( FIG. 47E ) is illustrated in  FIG. 185  and includes fingers  369 A and  365 A. Each finger  365 A,  369 A includes a flat surface  369 B that engages a flat surface  352 B,  352 C on an implant  352 A to prevent the implant  352 A from rotating about the longitudinal axis of body  364  ( FIG. 47E ). The shape and dimension of body  364  can vary as desired and can, by way of example and not limitation, take on the orthogonal shape of drive  786  in  FIG. 184 . Fingers  369 A,  365 A ( FIG. 185 ) deploy and release implant  352 A in a manner similar to fingers  365 ,  366 ,  368 ,  369  in  FIG. 47D . 
     Implant  650 A illustrated in  FIG. 186  is an alternate configuration of the implant  650  illustrated in  FIGS. 165 to 170 . Implant  650 A is generally used to separate a pair of vertebra V 3 , V 4 . In contrast, implant  650  is intended to laterally translate a pair of adjacent vertebra. Implant  650 A is similar in construction and operation to implant  650  except that translation member  651 A can include a smooth, and not serrated, upper surface  651 B. Upper surface  651 B can also be shaped or formed to permit surface  651 B to slide smoothly inwardly over vertebra V 3  in the direction of arrow X 8 , and to cause surface  651 B to engage vertebra V 3  and resist movement of surface  651 B over vertebra V 3  if surface  651 B is, after being inserted intermediate vertebrae V 3  and V 4 , displaced in a direction opposite that of arrow X 8 . 
     In use, base  652  is placed atop vertebra V 4  in the manner illustrated in  FIG. 186  such that nose  651 C of member  651 A is positioned outside vertebra V 3 . Member  653  is turned with an Allen wrench to displace member  651 A in the direction of arrow X 8  to force nose  651 C intermediate vertebra V 3  and base  652  such that vertebra V 3  and V 4  are separated and the distance X 7  intermediate the vertebra V 3  and V 4  increases. The shape and dimension of the various components of implant  650 A, and any other implants described herein, can vary as desired as long as the function heretofore described is achieved. 
     Instrument  800  illustrated in  FIGS. 187 and 188  includes handle  801  and distal end  802 . End  802  is preferably, but not necessarily rounded. End  802  can be orthogonal as is end  781 A in  FIG. 184 . In use, any desired method can be utilized to position end  802  anywhere intermediate two vertebrae, adjacent or in a disc  70  or other joint, or between two spinous processes or transverse processes. One presently preferred method consists of oscillating handle  801  in the directions indicated by arrows E 8  to pass end  802  through tissue to a desired location at or in a joint. Once distal end  802  is positioned between a pair of adjacent vertebra in the manner indicated in  FIG. 188 , handle  801  can be laterally displaced in any direction—including the directions indicated by arrows C 8 , D 8 , A 8 , and B 8 —in order to manipulate end  802  like the end of a lever to separate, rotate, or laterally displace vertebra  127 ,  128 . Similarly, when end  802  is in a disc  70 , is intermediate a pair of vertebra  127  and  128 , or is between two spinous processes or transverse processes, then handle  801  can be displaced to separate, rotate, and/or laterally displace vertebra. An opening (not shown) can be formed generally parallel to the longitudinal axis of handle  801  and end  802  to permit instrument  800  to slide along a wire or other elongate guide unit to facilitate insertion of instrument  800  at a desired location in a patient&#39;s body. End  802  can also function as an implant reversibly threaded or otherwise attached to handle  801 . End  802  can be detached from handle  801  intermediate two vertebrae (inside a disc  70 , anywhere intermediate a pair of vertebra  127  and  128 , between two spinous processes, between two transverse processes, etc.) after vertebrae  127 ,  128  are manipulated. 
       FIG. 189  illustrates the use of two or more implants in a joint to pivotally displace a joint member. A number of possible scenarios are illustrated in  FIG. 189  and described below; to position, separate (space apart) opposing tissue surface; reshape an intervertebral disc, and/or to alter the orientation of the vertebra. 
     In a first scenario, only implants  803  and  805  are utilized, and implant  804  is not utilized. Implant  803  is inserted between vertebra  315  and vertebra  315 A at the location shown in  FIG. 189 , after which implant  805  is inserted between spinous processes  806  and  807  at the location shown in  FIG. 189 . Implant  805  is sized to increase the distance D 9  between spinous processes  806  and  807 , and to upwardly displace spinous process  806  in the direction of arrow C 9 . This causes vertebra  315  to pivot about implant  803  and to generate compressive forces acting on implant  803  in the direction of arrow A 9  that tend to maintain implant  803  intermediate vertebra  315  and  315 A. 
     In a second scenario, only implants  804  and  805  are utilized, and implant  803  is not utilized. Implant  804  is inserted between vertebra  315  and vertebra  315 A at the location shown in  FIG. 189 , after which implant  805  is inserted between spinous processes  806  and  807  at the location shown in  FIG. 189 . Implant  805  is sized to upwardly displace spinous process  806  in the direction of arrow C 9 . This causes vertebra  315  to pivot about implant  804  and to generate compressive forces on implant  804  that tend to maintain implant  804  intermediate vertebra  315  and  315 A. 
     In a third scenario, only implants  803  and  804  are utilized, and implant  805  is not utilized. Implant  803  is inserted between vertebra  315  and vertebra  315 A at the location shown in  FIG. 189 , after which implant  804  is inserted between vertebra  315  and  315 A at the location shown in  FIG. 189 . Implant  804  is sized to upwardly displace spinous process  806  and vertebra  315  in the direction of arrows B 9  and C 9 . This causes vertebra  315  to pivot about implant  803  and to generate compressive forces on implant  803  that tend to maintain implant  803  intermediate vertebra  315  and  315 A. 
     In a fourth scenario, only implants  803  and  805  are utilized, and implant  804  is not utilized. Implant  805  is inserted between spinous processes  806  and  807  at the location shown in  FIG. 189 , after which implant  803  is inserted between vertebra  315  and  315 A at the location shown in  FIG. 189 . Implant  803  is sized to upwardly displace vertebra  315  in the direction of arrow A 10  to pivot spinous process  806  about implant  805  and to compress implant  805  intermediate spinous processes  806  and  807 . 
     In a fifth scenario, implants  803 ,  804 ,  805  are utilized. Implant  805  is inserted between spinous processes  806  and  807  at the location shown in  FIG. 189 , after which implants  803  and  804  are inserted between vertebra  315  and  315 A at the locations shown in  FIG. 189 . Implants  804  and  803  are sized to upwardly displace vertebra  315  in the directions indicated by arrows B 10  and A 10 , respectively. This causes vertebra  315  and spinous process  806  to pivot about implant  805  and to generate compressive forces on implant  805 . 
     Any desired combination of implants, as well as any desired sizes and shapes of implant, can be utilized to pivot a vertebra in the manners illustrated in  FIG. 189 . Implants  803 ,  804  and  805  can exert a force anywhere within or adjacent the spinous processes, transverse processes, face joints, intervertebral disc, etc. Implants  803 ,  804  and  805  can likewise function to alter the orientation of a vertebra  315 ,  315 A; to reshape a disc; and, to separate and lengthen tissues to decompress nerves or vessels (i.e., internal traction). Implants can be placed in any desired location and be constructed from any desired material. Implants can also be inserted into multiple intervertebral discs in a spine, including implants in intervertebral discs on each “side” or at each end of a vertebra in the spine. Implants in one intervertebral disc in a spine may work in tandem with implants in another intervertebral disc to achieve a desired result is spacing or positioning one or more vertebrae or discs. 
     The diagrammatic illustration of  FIG. 190  depicts an egg-shaped implant  805  interposed between an opposing pair of spinous processes  806  and  807 . Implant  805  does not prevent spinous processes  806  and  807  from laterally, slidably moving over implant  805  in the directions indicated by arrows R 8 . The shape and dimension and construction (i.e., one or more pieces, different materials, resiliency, flexibility, etc.) of implant  805  can vary as desired. 
     The diagrammatic illustration of  FIG. 191  depicts an egg-shaped implant  805 A including depressions  808  and  809  in which an opposing pair of spinous processes  806  and  807 , respectively, seat. Depressions  808  and  809  function to at least partially restrict the lateral movement of processes  806  and  807  in the directions indicated by arrows R 8  in  FIG. 190 . The shape and dimension and construction of implant  805 A can vary as desired. 
     The diagrammatic illustration of  FIG. 192  depicts an egg-shaped implant  805 B including depressions  808 A and  809 A in which an opposing pair of spinous processes  806  and  807 , respectively, seat. Depressions  808 A and  809 A more closely conform to spinous processes  806  and  807  than do depressions  808  and  809  (FIG.  191 ) and, consequently, tend to restrict to a greater degree lateral movement of spinous processes  806  and  807  in the directions indicated by arrows R 8  in  FIG. 190 . The shape and dimension and construction of implant  805 B and depressions  808 A and  809 A can vary as desired ( FIG. 192 ). By way of example, and not limitation, a depression  809 A can take on the flared shape indicated for depression  809 C. Such a flared shape can be advantageous because a spinous process tends to flare (i.e., its width tends to increase) at the edge of the process that is closest to the opposing spinous process. 
     Implants  805 ,  805 A and  805 B can be fabricated in part or in whole from a resilient material which, when placed between and contacted by a pair of spinous or transverse processes, is resiliently compressed by the processes to form indents  808 ,  809 ,  808 A, and/or  809 A ( FIGS. 190 to 192 ). 
     An implant, particularly a unitary implant, that restricts lateral movement of one spinous process in the direction of arrows R 8  (and therefore restricts rotation movement of the spinous process about the longitudinal axis of the spine) with respect to another opposing spinous process is one particularly desirable embodiment of the invention because such an implant causes an opposing pair of spinous processes to function in part like a facet joint. An implant  805 ,  805 A,  805 B can also be shaped and dimensioned and constructed to be positioned intermediate a pair of opposing transverse processes to limit, or prevent, the lateral rotation of the spinous processes about the longitudinal axis of the spine. In addition to allowing normal movement or rotation or restricting normal movement or rotation in the manner described above, an implant  805 ,  805 A,  805 B can be constructed to fuse together a pair of opposing spinous or transverse processes. 
     An implant  805 ,  805 A,  805 B ( FIGS. 190-192 ) and/or implant  816  ( FIG. 196 ) can also be constructed or positioned to restrict, in the manner of a facet joint, the transverse or shear movement of opposing processes and vertebra in the direction indicated by arrows R 9  ( FIGS. 189 ,  196 ). For example, in  FIG. 196 , positioning implant  816  in the location illustrated restricts transverse (i.e., shear) movement of processes  806  and  807  in the directions indicated by arrows R 9 . Alternatively, implant  805 C (FIG.  193 - 196 ) can be shaped and contoured to permit the rounded tips  806 A,  807 A (or other portions) of an opposing pair of processes to seat in implant  805 C so that transverse movement of the processes in the direction of arrows R 9  is restricted or prevented. 
     As is illustrated in  FIGS. 192 to 196 , one or more leg units  812  can be utilized to secure an implant  805 B,  805 C in position intermediate a pair of opposing spinous processes or transverse processes. The construction of a leg unit  812  can vary as desired. It is, however, presently preferred that a leg unit  812  include ball  811  and socket  814 , a leg  810  securing the ball  811  to the implant, and a leg  813 ,  815  securing the socket  814  to a vertebra, a transverse process, a spinous process, or other portion of the spine ( FIG. 193 to 196 ).  FIGS. 193 to 196  are diagrammatic illustrations illustrating leg units in conjunction with an implant  805 C. Legs  813  and  815  in  FIG. 194  do not utilize a ball and socket connection with implant  805 C. Instead, each leg  813  includes an elbow  814 A that secures the leg to implant  805 C. The ball and socket is an example but not a limitation of a poly axial or other joint pivotally attaching an implant to the spine. 
     If desired, an implant  816  ( FIG. 196 ) can be placed between opposing arcuate surfaces  817  and  818  of a pair of spinous processes  806  and  807 . 
       FIG. 197  illustrates another implant  820  that can be utilized within an intervertebral disc, intermediate a pair of spinous processes or transverse processes, or at another desired location at or in a joint. Implant  820  includes a hollow cylindrical housing  820 A with aperture  820 B formed at one end and a slot  820 C formed in the other end. Externally threaded end  827  of a screw  828 A is located inside housing  820 A. Head  828  is fixedly mounted on the other end of the screw  828 A, and slot  829  is formed therein. The screw  828 A is moved in the direction of arrow T 8  by pressing head  828  in the direction of arrow T 8  such that screw  828 A slides through aperture  820 B. Moving end  827  in the direction of arrow T 8  downwardly pivots and displaces blade  825  in the direction of arrow T 6 . Blade  825  is fixedly mounted on a cylindrical axle or pin. One end  823  of the pin is slidably received by slot  821 . The other end  824  of the pin is slidably received by slot  822 . A cylindrical hub is also fixedly mounted on the pin and includes internally threaded aperture  823 A. When the screw  828 A is moved in the direction of arrow T 8 , end  827  pivots blade  825  in the direction of arrow T 6 , displaces blade  825  in the direction of arrow T 8 , and causes ends  823  and  824  to slide along slots  821  and  822  in the direction of arrow T 5 . Continuing to move screw  828 A in the direction of arrow T 8 , and continuing to move blade  825  and ends  823  and  824  in the direction of arrow T 5 , eventually causes ends  823  and  824  to reach the end of their travel in slots  821  and  822 , and causes blade  825  to pivot about the pin and through slot  820 C to the deployed position indicated by dashed lines  825 A. At the time blade  825  reaches said deployed position, internally threaded aperture  823 A has rotated ninety degrees from the position illustrated in  FIG. 197  and is in alignment with externally threaded end  827 , and head  828  is near or contacts the end  820 E of housing  820 A. Turning head  828  in the direction of arrow T 7  turns end  827  into aperture  823 A and draws deployed blade  825 A toward end  820 E such that ends  823  and  824  slide along slots  821  and  822 , respectively, in a direction opposite that of arrow T 5 . This decreases the distance between head  828  and deployed blade  825 A such that blade  825 A and head  828  contact and compress therebetween side portions of tissue such as the spinous processes  806  and  807  ( FIGS. 189 to 196 ) when implant housing  820 A is positioned intermediate a pair of opposed spinous processes  806  and  807  in the manner of implant  805  in  FIGS. 189 and 190 , implant  805 A in  FIG. 191 , implant  805 B in  FIG. 192 ,  805 C in  FIGS. 193 to 196 , and implant  816  in  FIG. 196 . Alternatively, the distance between head  828  and blade  825 A can be decreased an amount that still permits some lateral or other movement of the opposing pair of spinous processes (or transverse processes if implant  820  is inserted therebetween). The mechanism utilized to deploy a blade  825 A and to draw together a head  828  and blade  825  can be constructed in any desired manner. Implant  820  can be inserted between a pair of opposing vertebra, and can be inserted in an intervertebral disc to compress tissue between head  828  and blade  825 A. 
       FIG. 198  illustrates an implant  830  including a deployable wing  833  stored in hollow cylindrical housing  830 A provided with a rounded semi-spherical nose  830 B. Wing  833  includes upstanding lip  834  sized such that lip  834  will not fit through slot  832 . Turning screw  831  in the direction indicated by arrow T 9  through internally threaded opening  830 C and against the canted edge of wing  833  displaces wing  833  through slot  832  in the direction of arrow T 10  until lip  834  bears against the inside of housing  830 A adjacent slot  832  and until wing  833  is in the deployed position indicated by dashed lines  833 A. When deployed, wing  833 A produces a greater surface area bearing within or against a vertebra, tissue surface, or other joint member and reduces subsidence of the implant  830  or attaches the implant  830  into the tissue. As can be seen in  FIG. 204 , wing  833  can have a downward arcuate shape  833 B. Wing  833 B tends to gather and displace vertebral material or other tissue toward housing  830 A. Wing  833 C in  FIG. 205  has a “T” shape. The shape and dimension of implant  830  and one or more wings  833 ,  833 A,  833 B,  833 C provided by the implant  830  can vary as desired. Implants  820 , blade  825 A ( FIG. 197 ), implant  830  ( FIGS. 198 ,  204 ,  205 ), and wings  833 ,  833 A,  833 B,  833 C ( FIGS. 198 ,  204 ,  205 ) can act to gather and displace tissue to create a passageway when the implants are oscillated. 
     A multi-part implant  835  is illustrated in  FIGS. 199 to 203 . Implant  825  includes base  836 , platform  838 , tab  838 A, socket  838 B, locking member  837 , and bolts  841 ,  842  that extend in part through base  836  and into member  837  to secure member  837  in the position depicted in  FIGS. 200 to 203 . Locking member  837  secures ball  839  of platform member  838  in socket  840  of base  836 . When the bottom of one vertebra is canted with respect to the top of an opposing vertebra, platform  838  pivots to better position implant  835  intermediate the vertebrae to engage said bottom and top surfaces. Platform  838  engages one of the vertebrae surfaces (for example, the bottom of the upper vertebra); base  836  engages the other (for example, the top of the lower vertebrae). Tab  838 A is fixed to member  838 . Tab  838 A functions to restrict movement of member  838  when tab  838 A resides with socket  838 B of base  836 . The controlled movement of member  838  on base  836  functions to restrict rotation of the vertebra and can protect the facet joint, intervertebral disc, or other structures of the spine. 
     Any implant disclosed herein—including but not limited to implant  352 A ( FIG. 185 ), implant  650 A ( FIG. 186 ), tip  802  of instrument  800  ( FIGS. 187 ,  188 ), tip  781 A ( FIG. 184 ), implants  803  to  805 ,  805 A,  805 B,  805 C,  820 ,  830 ,  835  ( FIGS. 189  to  205 )—can be cannulated and inserted using any method, including but not limited to using an elongate guide unit such as instrument  360  ( FIG. 47E ), instrument  340  ( FIG. 51 ), instrument  350  ( FIG. 52 ), instrument  760  ( FIG. 178 ), wire  780  ( FIG. 184 ), and implant system ( FIG. 184 ) to position a pair of opposing tissue surfaces and separate, lengthen and/or shape hard or soft tissue. Hard or soft tissue can include bone, cartilage, ligaments, tendons, joint capsules, intervertebral discs, etc. 
     As used herein, an instrument (i.e., a medical instrument) is an article that is utilized to perform an operation or other medical procedure performed on the body of the patient (human or animal) and that is, after the medical procedure is completed, not left in the body. Examples of instruments are scalpels, retractors, scissors, drills, etc. 
     As used herein, an implant is an article that is inserted in the body during an operation or other medical procedure performed on the body and that is, at the conclusion of the medical procedure, left in the body to perform a selected function. A catheter inserted in a patient&#39;s bladder to collect urine is therefore, until it is removed, an implant. Suture inserted in patient&#39;s body is an implant. Examples of implants disclosed herein include, without limitation, implants  352 A ( FIG. 185 ), implant  650 A ( FIG. 186 ), tip  802  of instrument  800  ( FIGS. 187 ,  188 ), tip  781 A ( FIG. 184 ) of instrument  781 , and implants  803  to  805 ,  805 A,  805 B,  805 C,  820 ,  830 ,  835  ( FIGS. 189 to 205 ), implant  380  of instrument  340  ( FIG. 51 ), and, implant  352  of instrument  350  ( FIG. 52 ). 
     In general, a medical procedure is concluded at the point implants are inserted and the medical instruments are no longer required to complete the procedure, and the patient leaves the operating room or is sent, “post-op”, to a recovery room in a hospital, home, or other facility. It is, of course, possible for a patient (human or animal) to require a further medical procedure and the use of instruments while in recovery (particularly while in intensive care) or after being removed from recovery, but once such a further medical procedure is completed and the patient is, “post-op”, out of the operating room or sent to or remains in recovery, that particular medical procedure is deemed completed. 
     It is possible for an article to function (1) only as an implant, (2) only as an instrument, and (3) both as an instrument and an implant. In what is a novel aspect of the invention, articles are provided that function both as an instrument and as an implant. This is demonstrated by the use of an implant to oscillate or otherwise pass through tissue to a location in a body where the implant is to be deposited. 
     The concave resilient spring A 10  of  FIG. 206  is inserted between a pair of adjacent vertebra, i.e. joint, to space the vertebra apart and to permit a desired tilt of one vertebra with respect to the other. If spring A 10  is stiff, spring A 10  limits the tilting of one vertebra with respect to another. If spring A 10  is not stiff, and is readily compressed, then spring A 10  permits more tilting of one vertebra with respect to another. When spring A 10  is inserted, upper end A 101  bears against one vertebra while lower end A 102  bears against the other vertebra. 
     The convex resilient spring A 11  of  FIG. 207  is inserted between a pair of adjacent vertebra, i.e. joint, to space the vertebra apart and to permit a desired tilt of one vertebra with respect to the other. If spring A 11  is stiff, spring A 11  limits the tilting of one vertebra with respect to another. If spring A 11  is not stiff, and is readily compressed, then spring A 11  permits more tilting of one vertebra with respect to another. When spring A 11  is inserted, upper end A 111  bears against one vertebra while lower end A 112  bears against the other vertebra. If the height of springs A 10  and A 11  is the same, and the resistance of each spring to compression (i.e., joint dampening by pressing ends A 101  and A 102 , or, ends A 111  and A 112  toward each other) is the same, spring A 10  ordinarily allows more tilt than spring A 11 . As the cant, or tilt, of one vertebra with respect to another increases, the resistance of spring A 10  or A 11  increases and tends to prevent or slow further tilting. In  FIG. 208 , dashed lines A 120  indicate the tilting of vertebra A 12  in the direction of arrow  121  with respect to vertebra A 13 . The tilting of vertebra A 12  is exaggerated for purposes of illustration. 
       FIG. 208  illustrates a cylindrical resilient spring A 14  inserted between a pair of adjacent vertebra A 12 , A 13  to space apart the vertebra and to permit a desired tilt, or canting, of one vertebra with respect to another. The upper end of spring A 14  contacts the bottom of vertebra A 12 . The lower end of spring A 14  contacts the top of vertebra A 13 . 
     The ovate implant A 15  illustrated in  FIG. 209  is fabricated from bone, metal, polymer, gel, or some other resilient material. If desired, an aperture can be formed through implant A 15  to permit the implant to slide along a guide wire to a desired location in a patient&#39;s body. Alternatively, implant A 15  can be slide through a hollow guide member to a desired location in a patient&#39;s body. One use of implant A 15  is to serve as a resilient spacer when inserted between a pair of vertebra. Another use is to permit one vertebra to tilt with respect to another when implant A 15  is inserted between a pair of vertebra. The implant can be slotted so the implant A 15  functions in a manner similar to a coil spring and has a structure similar to a coil spring. Slot A 15 A functions to absorb or dampen compressive loads applied to implant A 15  within a joint. 
     Another implant A 16  is illustrated in  FIG. 210 . Implant A 16 , as can implant A 15  ( FIG. 209 ) and A 18  ( FIG. 211 ) and A 20  ( FIG. 212 ) and A 21 A ( FIG. 212A ), be fabricated from any desired material. Implant A 16  is, however, presently preferably fabricated from a resilient material and includes upper concave surface A 17  with edge, or tooth, A 171 . 
     Implant A 18  illustrated in  FIG. 211  is presently, although not necessarily, fabricated from resilient material and includes groove A 19  that initially increases in width as the distance into groove from surface A 191  increases. 
     Implant A 20  illustrated in  FIG. 212  is presently, although not necessarily, fabricated from resilient material and includes upstanding tooth A 21  depending from surface A 212 . Implant A 21 A illustrated in  FIG. 212A  is presently, although not necessarily, fabricated from resilient material and is inserted into a joint and can function to dampen compressive loads and includes groove A 21 B that has an initial inverted pyramid opening A 21 D that inwardly tapers and decreases in width and then expands as the distance into the groove from the outer surface A 21 C increases to form a cylindrical opening A 21 E adjacent the inverted pyramid opening A 21 D. 
     Instrument A 32  in  FIG. 213  includes a tapered distal end or tip A 24 , proximate end or elongate handle A 22 , and outwardly projecting cam member A 25 . Cam member A 25  can be rounded or shaped and dimensioned to not cut tissue, or, if desired, can include an outer cutting edge. 
     When member A 25  is not shaped to cut tissue, instrument A 32  can be utilized in various ways. 
     A first application of instrument A 32  is to insert instrument A 32  in tissue such that cam A 25  is adjacent a principal vasculature or principal nerve. The instrument is then rotated a sufficient distance in a direction indicated by arrows A 23  about the longitudinal axis of elongate handle to permit cam A 25  to contact and laterally displace the principal vasculature or principal nerve away from the longitudinal axis of handle A 22 . Instrument A 32  is pushed further into tissue in a direction parallel to the axis of displacement. In this manner, cam A 25  assists in displacing principal vasculature or principal nerves to permit the safe passage of instrument A 32  and of an implant or other article carried by or mounted on instrument A 32 . 
     A second application of instrument A 32  is to insert instrument A 32  in tissue and then to rotate instrument A 32  in a direction indicated by arrows A 23  to separate the tissue to either form an opening in the tissue or to produce a portion of tissue (separate tissue) that is no longer connected to the adjacent portion of tissue. 
     When cam A 25  is provided with a cutting edge, then inserting tapered tip A 24  and cam A 25  into tissue and turning instrument A 32  in a direction indicated by arrows A 23  enables cam A 25  to cut tissue. A guide wire can be provided and cam A 25  can be housed within tip A 24 . Moving a guide wire along the interior of instrument A 22  can deploy recessed cam A 25  similar to deployable wing  833 A in  FIG. 198 . 
     The implant illustrated in  FIG. 214  includes a pair A 30 , A 26  of members that can be removably interlocked one with the other by sliding member A 30  into member A 26  such that U-shaped grooves interfit. The shape and dimension of members A 30  and A 26  can vary widely as long as members A 30  and A 26  can be interlocked or interfit one with the other. Apertures A 34  and A 35  are formed through members A 30  and A 26 , respectively, such that a wire can inserted through apertures A 34  and A 35  and the implant can be inserted by sliding the implant along a wire. Members A 30  and A 26  can function as an implant assembly of two components removably interfit as a unitary implant. Members A 30  and A 26  can slide along a guide member (not shown) through apertures A 34  and A 35 . A guide wire, (or hollow guide unit), can maintain the assembly as a unitary implant until dispensed at a selected location within the body, and the members A 30  and A 26  can remain unitary or separate into two portions. 
     Cutting instrument A 40  is illustrated in  FIGS. 215 to 217  and includes opening A 48  extending therethrough and bounded by cutting edges A 41  and A 45 . Aperture A 42  is formed through the front end A 46  of instrument A 40 . Aperture A 43  is formed through back end or handle A 44 . Apertures A 42  and A 43  permit a wire to pass therethrough and also through opening A 48  such that instrument A 40  can be slid along a guide wire, or through a hollow guide unit, to a desired location in a patient&#39;s body. Once instrument is at a desired location in the patient&#39;s body, it is rotated in the manner indicated by arrows A 47  ( FIG. 216 ) about the longitudinal axis of handle A 44  and instrument A 40  such that edges A 41  and A 45  contact and cut tissue. 
     Another cutting instrument A 50  is illustrated in  FIGS. 218 to 221  and includes opening A 58  extending therethrough and bounded by cutting edge A 55 . Aperture A 52  is formed through the front end of instrument A 50 . Aperture A 53  is formed through handle A 54 . Apertures A 52  and A 53  permit a wire to pass therethrough and through opening A 58  such that instrument A 50  can be slid along a guide wire or along a hollow guide unit to a desired location in a patient&#39;s body. Once instrument A 50  is at a desired location in the patient&#39;s body, it is rotated in the manner indicated by arrows A 56  ( FIG. 218 ) about the longitudinal axis of handle A 54  and instrument A 50  such that edge A 55  contacts and cuts tissue. 
     Still a further cutting instrument A 60 , similar to instruments A 40  and A 50 , is illustrated in  FIGS. 222 to 227  and includes opening A 68  extending therethrough and bounded by cutting edge A 61 . Aperture A 62  is formed through the front end of instrument A 60 . Aperture A 63  is formed through handle A 64 . Apertures A 62  and A 63  permit a guide wire to pass therethrough and through opening A 68  such that instrument A 60  can be slid along a guide wire, or through a hollow guide unit, to a desired location in a patient&#39;s body. Once instrument A 60  is at a desired location in the patient&#39;s body, it is rotated in the manner indicated by arrows A 66  ( FIG. 226 ) about the longitudinal axis of handle A 64  and instrument A 60  such that edge A 61  contacts and cuts tissue. 
       FIGS. 227A and 227B  illustrate an alternate embodiment A 60 A of the instrument A 60 . Instrument A 60 A includes aperture A 63 A extending completely through instrument A 60 A along the longitudinal centerline thereof. Handle A 64  is connected to elongate cylindrical neck A 65 . Handle A 64  facilitates insertion of edge A 61  in a patient&#39;s body and facilitates rotation A 69  of neck A 65  about the longitudinal axis of instrument A 60 A. 
     Cam A 25  in  FIG. 213 , instrument edges A 41  and A 45  in  FIG. 215 , edge A 55  in  FIG. 219 , and edge A 61  in  FIG. 227A  can be serrated, toothed, textured, etc., and can be configured as desired. 
     Implant insertion tool A 73  is illustrated in  FIGS. 228 to 231  and includes insertion end A 70  attached to one end of hollow handle A 75  and handle A 74  attached to the other end of handle A 75 . Tool A 73  is slidably mounted on a guide wire (not shown) that extends through aperture A 76  in handle A  74  ( FIG. 231 ), through hollow handle A 75  ( FIG. 230 ), and through aperture A 78  formed in insertion end A 70  ( FIG. 228 ). Tool A 73  could be slidably mounted in a hollow guide unit along with or without a guide wire. If an implant is mounted at end A 70 , the guide wire may also slidably pass through the implant. In use, tool A 73  is slid along the wire, or through a hollow guide unit, until end A 70  is at a desired location in an patient&#39;s body. An implant comparable to implant B 66  in  FIG. 230 ,  231 D is mounted on pin A 72  ( FIG. 230 ) or is otherwise mounted on end A 70 . Once the implant reaches a desired location, handle A 74  and/or handle A 75  is utilized to withdraw instrument A 73  from the patient&#39;s body. Pin A 72  slides out of the implant, leaving the implant intermediate a pair of vertebra, in a joint, or at another desired location in the patient&#39;s body. Pin A 72  is fixedly secured in aperture A 71  ( FIG. 228 ). Alternatively, pin A 72  is fixedly secured to the implant and slides out of aperture A 71  and remains in an implant when tool A 73  is extracted from a patient&#39;s body. Pin A 72  can also control rotation or the orientation of an implant turned onto threaded insertion end B 64  of instrument B 60  in  FIG. 231A . For example, when instrument B 60  is unthreaded from the implant (for example implant B 66  in  FIG. 231D ) and is removed from instrument A 73  pin A 72  prevents the implant from rotating. 
       FIGS. 231A ,  231 B illustrate an elongate instrument B 60  includes head or handle B 61  connected to one end of elongate neck B 62 . The other end B 64  of neck B 62  can, if desired, be internally or externally threaded to removably connected to a pin or aperture on an implant. Aperture B 63  extends completely along the length of instrument B 60  and along the longitudinal centerline of neck B 62  and permits a wire or other elongate guide member to be slidably inserted in aperture B 62  such that instrument B 60  can slide along the guide member to a desired location in a patient&#39;s body. 
       FIGS. 231C ,  231 D, and  231 E illustrate how instruments B 60  and A 73  can be utilized cooperatively by sliding the neck B 62  into hollow instrument A 73  in the manner indicated by arrow B 65  in  FIG. 231C .  FIG. 231D  illustrates instruments B 60  and A 73  assembled with an implant B 66  mounted and turned on externally threaded end B 64 . Pin A 72  ( FIG. 230 ) is slidably inserted in implant B 66  to prevent implant B 66  from rotating about the longitudinal axis of necks B 62  and A 75  ( FIGS. 231C and 230 ). The instrument assembly illustrated in  FIG. 231D  can slidably move along an elongate guide wire (not shown), through a hollow guide unit, or other guide member until implant B 66  is at a desired location in a patient&#39;s body. Handle B 61  is rotated in the direction indicated by arrow B 67  ( FIG. 231D ) to unthread end B 64  from implant B 66 . After end B 64  is unthreaded, instruments A 73  and B 60  are pulled along the guide wire in the direction of arrow B 68  in  FIG. 231D . Pin A 72  slides out of implant B 66 , leaving B 66  in place in the patient&#39;s body. 
       FIGS. 232 to 235  illustrate another instrument A 80  that can be utilized to penetrate, separate, or cut tissue. The pointed distal end of instrument A 80  includes conical surface A 82 . Handle A 87  is relatively short as pictured in  FIG. 232 , and normally is significantly longer so handle A 87  can, practically speaking, extend from a point exterior a patient&#39;s body to a location in the patient&#39;s body and can be manipulated as a lever. Although the length of the handle of an instrument can vary as desired, other handles that are shown in the drawings herein and that are relatively short typically are, in practice, longer. Aperture A 81  is formed through handle A 87  and the distal end of instrument A 80  such that a guide wire can be inserted through aperture A 81  and instrument A 80  can be slid—to a desired location in a patient&#39;s body—along the guide wire in a direction generally parallel to, but offset from, the longitudinal axis of instrument A 80 . Once the distal end of instrument A 80  is at a desired location in a patient&#39;s body, instrument A 80  can be rotated about a wire in aperture A 81  in the manner indicated by arrows A 83 . Instrument A 80  can be manipulated as a lever when inserted into a joint. Instrument A 80  can displace vertebra, altering the orientation, alignment, etc. of the vertebra, and/or shape of the disc when inserted intermediate two adjacent vertebra. Since aperture A 81  is offset from the longitudinal axis of instrument A 80 , instrument A 80  functions along its length like a cam, or lever, much like instrument A 32  illustrated in  FIG. 213 . Consequently, instrument A 80 , like instrument A 32 , can be utilized to pass by principal vasculature or principal nerves, can be used to separate tissue, and can, if provided with a cutting edge at its distal end, be used to cut or resect tissue. Handle A 87  includes end A 84 . Instrument A 80  can be hollow and used in a cam-like manner and/or as a lever, to separate, move, or displace tissue and principal blood vessels and nerves to safely deliver an implant to a desired location in a patient&#39;s body, as is described below in conjunction with  FIGS. 235E ,  235 F,  235 G,  235 H,  235 I. After instrument A 80  is slid over a guide wire, either instrument A 80  or the guide wire can function as an elongate guide unit. Another hollow instrument (not shown) or an implant can slide along the guide wire or instrument A 80 . 
       FIGS. 235A to 235D  illustrate another instrument C 60  that can be utilized to penetrate, separate, or cut tissue. The pointed distal end of instrument C 60  includes conical surface C 66 . Handle C 67  is relatively short as pictured in  FIG. 235A , and normally is significantly longer so handle C 67  can, practically speaking, extend from a point exterior a patient&#39;s body to a location in the patient&#39;s body and can be manipulated as a lever. Although the length of the handle of an instrument can vary as desired, other handles that are shown in the drawings herein and that are relatively short typically are, in practice, longer. Apertures C 61 , C 62 , and C 63  are formed through handle C 67  and the distal end of instrument C 60  such that a guide wire can be inserted through apertures C 61 , C 62 , or C 63  and instrument C 60  can be slid—to a desired location in a patient&#39;s body—along the guide wire in a direction generally parallel to, but offset from, the longitudinal axis of instrument C 60 . Once the distal end of instrument C 60  is at a desired location in a patient&#39;s body, instrument C 60  can be rotated about a wire in aperture C 61 , C 62 , or C 63  in the manner indicated by arrows C 69 . A wider circumferential tissue separation occurs when instrument C 60  is rotated about axis C 61  or C 63  when compared to moving tissue by rotating instrument C 60  about central axis C 62 . Conical surface portion C 65  with offset axes C 61  and C 63  provide instrument sections of at least two different widths. Instruments C 60  can function with variable axes of rotations. Since aperture C 61  (and C 63 ) is offset from the longitudinal axis of instrument C 60 , instrument C 60  functions along its length like a cam, much like instrument A 32  illustrated in  FIG. 213  and instrument A 80  illustrated in  FIGS. 232 to 235 . Consequently, instrument C 60 , like instruments A 32  and A 80 , can be utilized to pass by principal vasculature or principal nerves, can be used to separate tissue, and can, if provided with a cutting edge C 65  at its distal end, be use to resect tissue. Handle C 67  includes end C 68 . If a guide wire is inserted through central aperture C 62  or offset axis C 61 , C 63 , instrument C 60  can be utilized in a cam-like fashion in the manner described below with respect to hollow instrument A 80 B in  FIGS. 235E-I . Instrument C 60  can also function as an elongate guide unit after sliding over a guide wire and another hollow instrument (not shown) can slide over instrument C 60  or an implant can slide through instrument C 60 . 
       FIGS. 235E to 235H  illustrate a hollow embodiment A 80 B of instrument A 80 . Instrument A 80 B can, if desired, include a plunger or syringe B 72  that can function either to push an implant B 74  out end B 81  or, when syringe B 72  slidably seals against inner cylindrical surface B 73  of instrument A 80 B, can function to generate suction when syringe B 72  is displaced in the direction of arrow B  81  ( FIG. 235E ). When syringe B 72  is utilized to generate suction, it can draw tissue or an implant up into end B 81 . 
     The use of instrument A 80 B in a cam-like fashion is illustrated more precisely in  FIGS. 235F to 235H .  FIGS. 235F and 235G  illustrate instrument A 80 B inserted such that pointed, canted, end B 81  is adjacent a nerve B 76 . The oval mouth B 86  at end B 81  “opens up” in  FIGS. 235F and 235G . When instrument A 80 B is rotated in the direction of arrow B 78 , the peripheral oval-shaped edge of mouth B 86  contacts nerve B 76 , and, as instrument A 80 B continues to rotate, pushes nerve B 76  laterally in the direction of arrow B 77  and permits instrument A 80 B to move past nerve B 76  in the direction of arrow B 79  ( FIG. 235G ). After instrument A 80 B is rotated about a quarter-turn (the amount by which instrument A 80 B is rotated can, of course, vary as desired) or is laterally displaced, and is forwardly advanced, it is in the position illustrated in  FIGS. 235H and 235F  (as dashed lines A 80  BR), with mouth B 86  adjacent and generally conforming to the peripheral surface B 83  of disc B 75 . An alternate position A 80 B 2  of instrument A 80 B is also shown in  FIG. 235F  prior to instrument A 80 B 2  being rotated, laterally displaced, or forwardly advanced. The new position A 80 B 3  of instrument A 80 B after being laterally displaced is further illustrated in  FIG. 235I . Consequently, instrument A 80 B can, as desired, be rotated, laterally displaced, and/or forwardly advanced after instrument A 80 B is place in a desired position adjacent principal vasculature or nerves. 
       FIG. 235I  illustrates instrument A 80 B being inserted on a side of the spine opposite that illustrated in  FIG. 235F . Instrument A 80 B can be inserted in any desired direction as indicated by positioning end B 81  of instrument A 80 B in  FIG. 235F  and  FIG. 235I . Instrument A 80 B can be laterally displaced in the manner indicated by dashed lines A 80 B 3  in  FIG. 235I . 
       FIGS. 236 to 241  illustrate an implant A 90 , with apertures A 91  ( FIG. 237 ) and A 92  ( FIGS. 239 ,  241 ) that receive a guide wire and permit implant A 90  to slide therealong to a desired location in a patient&#39;s body. Aperture A 91  is formed in tip A 93 . Opening A 94  ( FIG. 237 ) extends through implant A 90  and can removably house in aperture A 94  a second component (not shown) such as bone, polymer, spring, etc. such that a guide wire or other guide member slidably extends through implant A 90  and through the second component such that the guide wire maintains the second component in a selected position in implant A 90 . Opening A 94  can extend to or from one or more sides of an implant. In  FIG. 237 , opening A 94  extends to four different sides of the implant A 90 . This provides ease of insertion between a pair of vertebra and implant A 90  can function between the vertebra regardless of the orientation of implant A 90  during, before, and after implant A 90  is inserted between the vertebra. When the implant A 90  is inserted, each one of an opposing pair of the sides ordinarily will always contact a pair of opposed adjacent vertebra, and, each of the sides will open on a portion of a second component housed in implant A 90 . 
       FIGS. 242 to 248  illustrate an implant B 10 , with apertures B 11  ( FIG. 243 ) and B 12  ( FIG. 248 ) that receive a guide wire and permit implant B 10  to slide therealong. Opening B 15  ( FIG. 242 ) extends through implant B 10 . Circular openings B 13  ( FIG. 247 ) may or may not be formed through wall of implant B 10 . Toothed openings B 14  are formed in implant B 10  and initially widen as the distance into the openings B 14  from the outer surface of implant B 10  increases ( FIG. 246 ). Toothed openings B 14  can be configured in any desired manner and can, for example, be configured with only a portion of the toothed opening diverging into the implant like opening A 21 B in  FIG. 212A . 
       FIGS. 249 to 252  illustrate a “boat” implant B 20  that includes outwardly extending flat surfaces B 21  ( FIGS. 249 to 252 ) that are intended to help prevent subsidence of implant B 20  into a vertebra or other tissue. Beveled flat surfaces B 24 , B 25  can also function to align implant B 20  diagonally within an elongate guide unit such as orthogonal implant cannula  783  ( FIG. 184 ). Surfaces B 24 , B 25  can conform to and slide along an interior portion of cannula  783 . Aperture B 24  formed in tip B 22  ( FIG. 250 ) and aperture B 23  receive a guide wire  780  ( FIG. 184 ) that also extends through opening B 25  such that implant B 20  can slide along the guide wire to a desired location in a patient&#39;s body, after which the guide wire is removed, leaving the implant. Opening B 25  ( FIG. 251 ) extends through implant B 20  and can house a second component (not shown) such as bone, polymer, spring, etc. such that a guide wire or other guide member slidably extends through implant B 20  and through the second component such that the guide wire maintains the second component in a selected position in implant B 20 . Opening B 25  can extend to or from one or more sides of an implant. 
       FIGS. 253 to 259  illustrate an implant B 30  that includes opening B 35  ( FIGS. 258 ,  253 ) formed therethrough and includes apertures B 42  ( FIG. 261 ) and B 31  (FIG.  258 ) that receive a guide wire extending through implant B 30  so that implant B 30  can slide along the guide wire to a desired location in a patient&#39;s body, after which the guide wire is, as is usually the case when implants are inserted in a patient&#39;s body, removed. Openings B 33  ( FIGS. 257 ,  258 ) may or may not be formed through a wall of implant B 30 . Toothed openings B 34  ( FIGS. 257 ,  258 ,  259 ) are formed on implant B 30 . Toothed openings B 34  can also be configured in any desired manner and can, for example, be configured like opening A 21 B in  FIG. 212A . 
       FIGS. 260 to 267  illustrate an implant B 40  that includes opening B 47  ( FIG. 265 ) formed therethrough and includes apertures B 42  ( FIG. 261 ) and B 44  ( FIG. 267 ), each of which receive a guide wire that extends through implant B 40  such that implant B 40  can slide along the guide wire to a desired location in a patient&#39;s body. Aperture B 42  extends through nose B 46 . Toothed openings B 41  ( FIG. 261 ) are formed in implant B 40 . 
       FIGS. 268 to 272  illustrate a two piece implant B 50  that includes body members nose B 51  pivotally attached to tail B 52  by hinge pin B 53 . Implant B 50  functions in a manner similar to implant  502  in  FIGS. 110-112 . Apertures are formed through implant B 50  such that it can received and slide along a guide wire to a desired location in a patient&#39;s body. Nose B 51  can either remain attached to tail B 52  by pin B 53  or can detach from tail B 52  after being dispensed from a guide wire (not shown) or hollow guide unit. Implant B 50  can function as one or two implants, one implant when the nose and tail remain attached, and two implants when the nose and tail separate. Body members nose B 51  and tail B 52  can articulate on hinge pin B 53  after implant B 50  is dispensed from an elongate guide unit. The elongate guide unit can comprise, for example, a guide wire or hollow guide tube or member. The degree or amount that implant B 50  and implant  502  ( FIGS. 110-112 ) articulate while moving in or along a joint (or disc) depends on the resistance, shape, elasticity, hardness, etc. of the joint (or disc). Implant B 50  can consist of a string of two or more pivotally connected, articulating body members. 
     Problems associated with inserting an implant in a joint, including by way of example and not limitation, an intervertebral disc, include identifying the general location of the subject disc, identifying the location of an instrument with respect to the subject disc, and identifying the specific desired or damaged location in the disc or intermediate a pair of vertebra. 
     One method of facilitating locating a subject disc comprises first identifying, by fluoroscopy the general location of the disc, then by light source, camera, arthroscopy, endoscopy, laparoscopy, open direct visualization, or other means, observing the disc. 
     One specific method of locating a diseased, injured, degenerated, or otherwise damaged portion in the disc is by observing the color, texture, contrast, shape, elasticity, hardness, etc. relative to the color, texture, contrast, shape, elasticity, hardness, etc. of a normal, healthy, undamaged portion of the disc. 
     Another method of locating a diseased, injured, degenerated, or otherwise damaged portion in the disc is by observing the color, texture, contrast, shape, elasticity, hardness, etc. relative to the color, texture, contrast, shape, elasticity, hardness, etc. of a normal, healthy, undamaged portion of the disc after staining, injecting contrast, removing tissue or manipulation. 
     Another specific method of locating a damaged portion in the disc is by observing the color, texture, contrast, shape, etc., of tissue adjacent the disc after contrast or colored dye is inject inside the nucleus of the disc, and leaks out from the disc through a tear staining or highlight the preexisting rupture or openings made in the disc, identifying the disc portion to be treated and or location for an implant to be inserted. 
     Diseased, injured degenerated, or otherwise damaged tissue appears torn, ruptured, frayed, rough, discolored, deformed, etc., compared to normal smooth, healthy tissue. Likewise, damaged tissue accepts stain, contrast, light, etc., differently from normal undamaged tissue. Variation in tissue color, shade, contrast, texture, shape, etc., can reveal the degree to which the tissue is damaged. 
     The operator palpating tissue with an instrument can locate a damaged portion. A surgeon pushing a needle or guide wire in a disc can determine the elasticity or hardness of the annulus and locate a tear. 
     The surgeon clinically determines superficial (skin) landmarks corresponding to a disc (joint) location and inserts a needle into the skin. The needle is advanced towards the disc using fluoroscopy, x-ray, ultrasound, computer tomography, or other means. The disc is palpated and penetrated with the needle. A guide wire is inserted along the needle further palpating the disc. The needle can be removed. A dilator can be inserted along the guide wire. A hollow guide unit can be inserted along the dilator. The dilator can be removed. A light source, camera, arthroscope etc., can be inserted along the guide wire, with or without using the dilator, and/or along the hollow guide unit. The disc is visualized. The disc can be treated and/or implant inserted. Positioned instruments, treated disc and/or the inserted implant can be visualized with a fluoroscope, light source, camera, arthroscope, or any desired means. 
     Another specific method of identifying the desired area of the disc is by changing the color, texture, contrast, or shape of a portion of the disc. One way of changing the color, contrast, texture, shape, etc., of a particular area of a disc is by resecting a portion of the disc. This causes blood vessels within tissues, vertebra, etc., adjacent the disc to bleed, which changes the color of the disc. One way of changing the color of a particular area of a disc is by using a syringe or other means to inject a dye (a colored dye or contrast dye) into a particular area of the disc to change the color and/or contrast of the disc. When the color and/or contrast of a disc or portion of a disc (or vertebra) is altered, the location of an instrument in a patient&#39;s body can be determined with a fluoroscope or other means and correlated with the location of the portion of the disc that has changed color and/or contrast. Similarly, removing damaged tissue by smoothing or roughening the disc can prepare the disc for an implant. Manipulating a disc or vertebra with any of the instruments discussed herein can change the shape of the disc or joint. A colored dye can sometimes function as a contrast dye when viewed radiographically, viewed with a camera, or viewed by any other desired means. 
     Other physical or chemical or electrical properties of a disc (or vertebra or joint or nerve or blood vessel) can be monitored to facilitate locating the disc and locating the position of an instrument with respect to the disc. For example, the initial contrast, hardness, elasticity, texture, conductivity, or other property of the disc or adjacent tissues can be determined, followed by monitoring the disc, or an area of the disc, or area adjacent the disc, to determine when and if a change in the property occurs in order to safely insert an instrument, treat tissue, and/or insert an implant. 
     In an alternate embodiment of the invention, a hinged implant (for example, implant B 50  ( FIG. 270 ) is provided with a pin B 53  or other hinge made of metal. The hinge interconnects the nose B 51  and tail B 52 . The nose B 51  and tail B 52  are made from a polymer. The metal pin B 53  facilitates location of the implant B 50  in an individual&#39;s body or joint because the pin B 53  is fabricated from metal and can be more readily located radiographically or by other desired methods. 
     In a further embodiment of the invention instruments and/or implants are adapted (configured) to pass by flexible devices previously inserted, which flexible devices can, for example, comprise a flexible wire or cannula. A rod or other support member that is secured along and inside or outside the spine or another joint can have an access portion that includes an opening that permits a desired instrument to access a particular selected area of the spine. The access portion can, by way of example and not limitation, be hollow, be C-shaped, be bent, be curved, be straight, or extend laterally to one side of a desired area of the spine. Consequently, a rod secured along the spine can have a C-shaped portion connected to and intermediate straight portions of the rod. When the rod is installed, the C-shaped portions extends around a selected area of the spine and permits ready access to the selected area of the spine by a particular instrument or instruments or implants. The implants and instruments described herein can be constructed of rigid, semirigid, or resilient (flexible, elastic, etc.) material to conform around implants or instruments or joints or discs, through openings in implants or instruments or joints or discs, or adjacent to existing implants or instruments or joints or discs. 
     Use of Spring and Hinge in Implants 
     In one embodiment of the invention, an implant comprises a spring. See  FIGS. 16 ,  17 ,  28 ,  29 ,  206 ,  207 , and  209 . 
     In another embodiment of the invention, an implant includes a spring that functions to space apart and separate portions of an implant. See  FIG. 208 . 
     In a further embodiment of the invention, an implant functions as a hinge. See, for example,  FIGS. 34 to 40 . 
     In still another embodiment of the invention, an implant includes a hinge. The hinge can be generally horizontally oriented in the manner illustrated in  FIG. 90  (pin  483 ),  150  to  152  (pin  603 ),  161  to  163  (pin  621 ),  172  to  175  (pins  675 ,  679 ),  192  (leg  810 ), or, the hinge can be generally vertically oriented in the manner indicated in  FIGS. 110 to 112  (pin  503 ),  149  (pin  422 ),  199  to  201  (ball and socket), and  268  to  271  (pin B 53 ). Other pivots or hinges are illustrated in  FIG. 1  as shaft  59 , members  42 A and  43 A, and cam  10 , in  FIG. 9  as device  76 , in  FIGS. 35 and 36  as apparatus  230 , in  FIGS. 37 and 38  as apparatus  234 , in  FIGS. 39 and 40  as apparatus  245 , etc. 
       FIG. 273  illustrate a spring B 67  and hinge B 64  utilized in combination to open an implant by causing portions B 61 , B 62  of implant B 60  to pivot about hinge pin B 64  extending through each of said portions. Portions B 61 , B 62  presently are fabricated from rigid metal, but can be constructed from elastic material, from bendable material, or from any desired material. When implant B 60  is being inserted at a desired location in the body of a patient, in particular at a desired location in the spine of the patient, implant B 60  slides along a guide wire extending through elongate apertures B 71  and B 72  (shown in  FIG. 275 ). The wire is sized such that apertures B 71  and B 72  are, in contrast to the misalignment of apertures B 71  and B 72  in  FIG. 275 , co-linear and in alignment. When apertures B 71  and B 72  are in alignment, portions B 61  and B 62  are in alignment in a linear configuration; stop surfaces B 65  and B 66  are, in contrast to  FIG. 273 , spaced apart from and do not contact each other; and, spring B 67  is compressed between and extends from opening B 73  in portion B 61  to opening B 74  in portion B 62  ( FIG. 275 ). If desired, in addition to or in place of the guide wire, implant B 60  can be inserted in the body of a patient by sliding implant B 60  down an elongate guide tube, sleeve, or other guide unit or member that functions to maintain implant B 60  in alignment and to prevent portions B 61  and B 62  from pivoting about hinge pin B 64 . As soon as implant B 60  leaves an end of the guide wire, or leaves the end of the elongate guide tube, portions B 61  and B 62  are free to pivot about hinge pin B 64 ; and, compressed spring B 67  expands and causes portion B 62  to pivot about hinge pin B 64  in the manner indicated by arrows B 68  and B 69  so that portions B 61  and B 62  assume the open arcuate orientation illustrated in  FIGS. 273 to 275 . When implant B 60  is in the open orientation illustrated in  FIGS. 273 to 275 , stop surfaces B 65  and B 66  contact each other in the manner illustrated in  FIG. 273  and prevent further pivoting of portions B 61  and B 62  about hinge pin B 64  in the direction of arrow B 68 . The size and shape of apertures B 71  and B 72  can vary as desired. Conically shaped openings B 71 A, B 72 A function to prevent a guide wire from binding by producing a smooth arcuate path between apertures B 71  and B 72  when these apertures are canted with respect to one another. This is important because when spring B 67  expands and causes portion B 61  to pivot and cant with respect to portion B 62 , portions of the sides of apertures B 71  and B 72  are forced against a wire extending through said apertures and, accordingly, generate frictional forces acting on the wire. Consequently, openings B 71 A and B 72 A facilitate implant B 60  smoothly sliding along a wire extending from portion B 61  to portion B 62  of implant B 60 . 
     If desired, in another embodiment of the invention, instead of utilizing a tensioned spring B 67  that functions to push apart portions B 61  and B 62  in the manner illustrated in  FIGS. 273 to 275 , a tensioned spring, indicated by dashed line B 78  in  FIG. 273 , can be utilized that functions to pull portions B 61  and B 62  from a linear orientation to the open orientation that is illustrated in  FIGS. 273 to 275 . When such a tensioned “pulling” spring is utilized in place of the “pushing” spring B 67 , the portions B 61  and B 62  of implant B 60  are still maintained in a linear orientation while the implant B 60  slides down a guide wire or along a guide tube. Once the implant B 60  exits the guide wire or guide tube, spring B 78  ( FIG. 273 ) pulls portions B 61  and B 62  from the linear orientation to the open arcuate orientation illustrated in  FIGS. 273 to 275 . 
     The spring utilized to push or pull portions B 61  and B 62  into an open orientation (or from an open orientation into a linear orientation) can be mounted on the exterior of and extend between portions B 61  and B 62  in the manner indicated by dashed lines B 77  in  FIG. 273 . If desired, implant B 60  can reform or articulate from a first linear configuration to a second arcuate configuration simply by contacting a resistance within a joint after the implant B 60  is released from a guide unit. As utilized herein, reform means to change shape. Conform means to chance shape in response to forces generated by an adjacent joint or other tissue. 
     Multiple Articulations 
     The implant B 60  has a single articulation, i.e., has a single articulating joint. As is illustrated in  FIGS. 276 to 281 , an implant B 80  can have two or more articulations. Implant B 80  has three articulations. Implant B 80  includes portions B 81 , B 82 , B 83 , and B 84 . Hinge pin B 85  pivotally interconnects portions B 81  and B 82 . Hinge pin B 86  pivotally interconnects portions B 82  and B 83 . Hinge pin B 87  pivotally interconnects portions B 83  and B 84 .  FIGS. 276 to 278  illustrate implant B 80  in a linear orientation.  FIGS. 279 to 281  illustrate implant B 80  in an open, arcuate orientation. When implant B 80  is in a linear orientation, it extends over an area of an adjacent joint or other tissue that is generally circumscribed and indicated by dashed lines B 88  in  FIG. 276 . When implant B 80  is in an open, arcuate orientation, it extends over an area of an adjacent joint or other tissue that is generally circumscribed and indicated by dashed lines B 89  in  FIG. 279 . The area indicated by dashed lines B 89  is greater than the area indicated by dashed lines B 88  because hinge pins B 85 , B 86 , B 87  are spaced apart from the elongate centerline BX of implant B 80  ( FIG. 276 ) and permit implant B 80  to articulate into an open arcuate orientation. When implant B 80  is in the linear orientation of  FIG. 276 , opposing surfaces C 22 , C 23  are adjacent (and surface C 20  and C 21  are each adjacent to their opposing surface), and stop surfaces C 24  and C 25  are spaced apart. After portions B 81  to B 84  each pivot about their respective hinge pins B 85  to B 87 , surfaces C 22  and C 23  are spaced apart (i.e., have “opened”) and stop surfaces C 24  and C 25  are adjacent one another. In  FIG. 279 , implant B 80  is in an “open” arcuate orientation, and the pie-shaped opening or space extending between the opposing pair of surfaces C 22  and C 23  is larger than the pie-shaped opening extending between the opposing pair of surfaces C 24  and C 25  in  FIG. 276 . In  FIG. 276 , implant B 80  is in a “closed”, linear orientation. Since the pie-shaped opening between opposing surface pair C 22  and C 23  (and other comparable surface pairs in articulating implant B 80 ) in  FIG. 279  is larger than the opening between opposing surface pair C 24  and C 25  in  FIG. 276  (and other comparable surface pairs in implant B 80 ), when implant B 80  is in the non-linear arcuate orientation of  FIG. 279 , it extends over a greater surface area of a joint than when implant B 80  is in the linear orientation of  FIG. 276 . This result is achieved in implant B 80  because pivot pins B 85  to B 87  are laterally spaced away from centerline BX ( FIG. 276 ). 
     If, after an implant is inserted in a joint, the implant alters shape and the joint surface area over which the implant extends is increased, such an increase tends to minimize migration of the implant and to reduce the amount of subsidence of the implant into adjacent joint tissue. 
     The hinge pin B 64  ( FIG. 275 ) for implant B 60  is also, like hinge pins B 85  to B 87 , spaced apart from the center line that passes through implant B 60  when implant B 60  is in a linear orientation. This offsetting of pin B 64  facilitates the articulation of implant B 60  from a linear orientation to an open, arcuate orientation. The size of the area covered by implant B 60  can, however, also be increased if pin B 64  is, instead of being offset from the centerline BX of implant B 60 , positioned on the centerline. This is accomplished by placing pin B 64  in a slot B 70  that permits pin B 64  to slide along the slot so that portion B 62  is pushed away from portion B 61  by a compressed spring that extends between portions B 61  and B 62 , or, is pushed away from portion B 61  by forces generated and acting on portion(s) B 61  and/or B 62 . If desired, the spring can, like pin B 64 , be positioned along the centerline of implant B 60  that exists when implant B 60  is in a linear orientation. This could permit portion B 62  to be pushed directly away from portion B 61  such that portion B 62  does not cant away from a linear orientation in the manner that portion B 62  cants away from a linear orientation in  FIG. 275 . 
     Hinge Pins 
     In  FIGS. 273 to 281 , the hinge pins B 64 , B 85  to B 87  are each positioned between the centerline and periphery of implants B 60  and B 80 , respectively. If desired, a hinge pin B 96  can be positioned at the convex periphery of an elliptical implant B 95  in the manner illustrated in  FIG. 282 . When portions B 97  and B 98  of implant B 95  pivot about pin B 96  in the direction of arrow B 99  from the linear orientation of  FIG. 282  to the arcuate open orientation of  FIG. 283 , pin B 96  is said to reside at a concavity of implant B 95  because the inner side of implant B 95  on which pin B 96  resides in  FIG. 283  has taken on a concave shape. In contrast, in  FIG. 282 , pin B 96  is said to be located at a convexity of implant B 95  because the side of the implant at which pin B 96  is located has a convex shape. 
     In  FIG. 284 , hinge pin C 11  is located at a concavity of implant C 10 . In  FIG. 285 , after portions C 12  and C 13  have pivoted about pin C 11  in the direction of arrow C 14  to the linear orientation of  FIG. 285 , hinge pin C 11  is located at a convexity of implant C 10 . 
     In  FIG. 286 , hinge pin C 16  is located at a concavity of implant C 15 . Implant C 15  is in a closed linear orientation. In  FIG. 287 , after portions C 17  and C 18  have pivotally moved about hinge pin C 16  in the direction of arrow C 19  to the open orientation illustrated in  FIG. 287 , hinge pin C 16  is still located at a concavity of implant C 15 . 
     Fixation with Hinge 
     In one embodiment of the invention, a hinge pin or other hinge is provided with a tooth B 75 , B 76  or other fixation structure that extends outwardly from an implant B 60  ( FIG. 274 ). This fixation structure engages, and may penetrate, bone, cartilage, a disc, vertebra, or any other tissue that is adjacent the implant and functions to help secure or fix the implant in position adjacent the tissue. One virtue of this structure is that even though the top and/or bottom of the hinge can engage and be in a relatively fixed position, this normally does not prevent operation of the hinge and does not prevent one portion B 61  of an implant from rotating with respect to another portion B 62  of the implant, particularly just after the implant has been inserted at a desired location in the body of a patient. Other examples of implant structures that are associated with hinges and that help with teeth to fix an implant in position can be seen in  FIGS. 172 and 201 . 
     Positioning Implant in Joint 
     In one embodiment of the invention, implant B 60  is moved along a guide wire to a selected location in a joint or other tissue and only leading portion B 61  or B 62  is dispensed from the end of the guide wire at a selected location. As soon as portion B 62  is dispensed, spring B 67  causes leading portion B 61  or B 62  to pivot about hinge pin B 64  such that implant B 60  takes on the orientation shown in  FIG. 275 . The implant B 60  is then pushed completely off the guide wire so that the implant B 60  moves from the selected location in the joint to another, second, location in the joint. When the implant is moved to the second location in the joint, the implant can encounter resistance which makes leading portion B 61  or B 62  move in a direction opposite that of arrow B 68  so that portion B 62  overcomes resistance offered by spring B 67  and compresses spring B 67 , so that leading portion B 61  or B 62  pivots about pin B 64 , and so that openings B 73  and B 74  move somewhat closer together without implant B 60  returning to its original linear orientation. When openings B 73  and B 74  move closer together, implant B 60  take on another, third, configuration that is intermediate its original linear configuration and the open configuration illustrated in  FIGS. 273 to 275 . Likewise, if an implant has two or more articulations, the implant will have the ability to sequentially articulate as it is dispensed and freed from the confines of a guide unit. When the hinge pin of the implant moves free from the guide unit, it is, even though it is linked to an implant portion that is still on and under the constraints of the guide unit, free to articulate to some extent about a hinge or pivot point shared with the portion that is still on and under the constraints of the guide unit. The remaining portion(s) of the implant that are still in or on the guide unit are restricted by the guide unit and normally can only slide up or down the guide unit. When each of the remaining portions is dispensed from the end of the guide unit, these units too are free to articulate or move. Implant B 60  can be at least partially inserted into a joint in a first linear configuration, articulate to a second intermediate configuration, be fixed to the joint by toothed hinge pin B 75 , B 76 , and further articulate to at last a third arcuate configuration. Implant B 60  can also assume an expanded arcuate configuration by lengthening when a pin on a portion of implant B 60  slides along slot B 70  in  FIG. 275 . 
     The configuration of an implant can, if desired, also vary (i.e., expand or contract) along its length to conform to the shape of a joint. 
     Examples of implants that function to dampen the movement of a joint are seen in  FIG. 1 , where movement of portions of the implant  100  absorb energy, and are seen in the slotted spring-like implant A 15  in  FIG. 209 . 
     An implant that functions to fuse together opposing joint surfaces can be achieved by filling opening B 81 A in  FIG. 279  with bone or other osteogenic material that fuses to a joint. 
     In another embodiment of the invention, an implant functions to seal an opening in a disc (or other tissue) because when the implant is dispensed through an opening in the disc to occupy at least a portion of the interior of the disc, the implant changes shape by enlarging, by articulating to a curved orientation from a linear orientation, etc. This change in shape makes it more difficult for the implant to escape from the disc through the opening that was originally used to insert the implant in the disc. When the implant changes shape it can also function to block the opening in the disc, making it difficult to insert other instruments or material in the disc. 
     If desired, hinge pin B 86  in  FIG. 276  can be positioned opposite hinge pins B 85  and B 87  (on the other side of centerline BX of implant B 80 ). When hinge pin B 86  is positioned on the other side of centerline BX and hinge pins B 85  and B 86 , and when implant B 80  is articulated, implant B 80  assume a zig-zag shape wherein hinge pin B 86  remains in the concavity of portions B 82  and B 83 , and wherein hinge pin B 87  remains in the concavity of portions B 83  and B 84 , and wherein hinge pin B 85  remains in the concavity of portions B 81  and B 82 . 
     Having described my invention in such terms as to permit those of skill in the art to understand and practice the invention, and having described presently preferred embodiments thereof,