Patent Publication Number: US-7713290-B2

Title: Vertebral stabilization assembly and method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This patent application is a continuation-in-part of U.S. patent application Ser. No. 11/086,834, filed Mar. 22, 2005, which is a divisional of U.S. patent application Ser. No. 10/109,172, filed Mar. 28, 2002, now U.S. Pat. No. 6,899,714, issued May 31, 2005, which claims priority, to U.S. Provisional Patent Application No. 60/327,118, filed Oct. 3, 2001, U.S. Provisional Patent Application No. 60/350,259, filed Nov. 2, 2001, U.S. Provisional Patent Application No. 60/331,857, filed Nov. 20, 2001, and U.S. Provisional Patent Application No. 60/353,691, filed Jan. 31, 2002, each of which is hereby incorporated by reference herein in its entirety. 

   TECHNICAL FIELD OF THE INVENTION 
   The present invention relates generally to a spinal stabilization and more specifically, but not by way of limitation, to a vertebral stabilization assembly and method for stabilizing vertebra. 
   BACKGROUND OF THE INVENTION 
   The human spine frequently requires surgery to repair deformities or injuries. Spinal problems may be caused by a trauma to the spine received during an accident, excessive strain or stress on the spine from physical activities, a sedentary lifestyle and poor posture that may place abnormal pressure on the spine, disease or a variety of other reasons. Spinal fusion is a common surgery intended to alleviate pain caused by these spinal deformities or injuries. 
   The spinal fusion procedure generally includes removing the disk, packing bone graft between the vertebrae and placing a spinal implant, such as screws attached to a plate, rod or cage, to fuse elements of the spine together. Once the disk is removed and the bone graft is placed between the vertebrae, the bone graft will fuse to the vertebrae over a period of several months following the surgery. 
   The purpose of the plate is to stabilize the vertebrae until the bone graft has become fused to the vertebrae. The plate is positioned to extend between at least two vertebrae. The plate is attached to screws anchored in each of the adjacent vertebrae, thus immobilizing the desired portion of the spine. The plate is anchored to the screws either on the front, anterior, or back, posterior, sides of the vertebrae. 
   The present invention is not intended to be limited to applications in a specific region of the spine, and may, in fact, be utilized equally well with the cervical, thoracic, lumbar and sacrum vertebrae of the spine. However, for purposes of explanation, the surgical procedure will be discussed in greater detail with respect only to the lumbar vertebrae region of the spine. Procedurally, anterior, or entry from the stomach region of the patient, lumbar vertebra surgery provides the surgeon with optimum access to the entire intervertebral disk. Posterior, or entry from the back of the patient, surgery is less preferred since access to the disk is restricted. Once the anterior lumbar discectomy, or removal of the lumbar disk, is completed, the bone graft is placed into the space between the vertebrae previously occupied by the disk. 
   The patient is then positioned for posterior fusion, or placement, of the plate. The stabilization is typically accomplished by placing a screw in each of the lumbar vertebra such the screw extends through a portion of the vertebra and into the body of the vertebra. Each screw extends posteriorly from the vertebra sufficient for attachment to the plate. The plate is then anchored to each of the screws to retain the adjacent lumbar vertebrae positioned a distance from each other. The plate and screws thereby stabilize the lumbar vertebrae and provide time for the vertebrae and bone graft to fuse into a solitary unit. 
   However, posterior fusion requires large posterior muscle dissection to safely implant the pedicle screws and provide for placement of the plate. Such major muscle damage presents a danger to the patient during surgery from infection and the extensive muscle damage. Also, additional time is required to perform both extensive anterior and posterior surgical portions. The added surgical time presents another risk to the patient. 
   Attempts to eliminate the negative aspects of posterior fusion include anterior placement of the plate and screws. Although anterior fusion avoids the problems associated with the larger posterior fusion, additional problems arise. In such systems, the anchoring screws are laterally placed on the anterior of the vertebra. Lateral placement requires a significantly more invasive procedure and much greater exposure. Also, screws anchored laterally through the anterior of the vertebra do not provide the stability of those extending posteriorly through the pedicle and into the vertebral body. Furthermore, anteriorly-anchored screws do not promote quick and uniform fusion of the bone graft to the vertebra since they do not have the stability of the pedicle fixation. 
   Thus a need exists for a vertebral stabilization assembly that obtains the benefits while overcoming the disadvantages of prior procedures and systems. 
   SUMMARY OF THE INVENTION 
   The present invention provides a vertebral stabilization assembly for stabilizing vertebra. In one exemplary embodiment, the vertebral stabilization assembly includes a first and a second pedicle screw, a first and a second connecting screw and a connecting member. The first pedicle screw has a shaft provided with a threaded portion operable for threading engagement of the first pedicle screw with a first vertebra, the shaft also has an engaging portion. The first connecting screw has a first end adapted to be received by the engaging portion of the first pedicle screw. 
   The second pedicle screw has a shaft provided with a threaded portion operable for threading engagement of the pedicle screw with a second vertebra. The shaft of the second pedicle screw has an engaging portion. The second connecting screw has a first end adapted to be received by the engaging portion of the second pedicle screw. The connecting member has a first end and the second end. The first end of the connecting member connected to the first connecting screw positionable in the first vertebra. The second end of the connecting member connected to the second connecting screw positionable in the second vertebra for stabilization of the first vertebra and the second vertebra. 
   In one aspect, the connecting member may be a rod, bracket, plate or brace. In other aspects, the first and second connecting screws are each provided with an opening in a second end thereof and wherein the first end of the rod is positionable in the opening in the second end of the first connecting screw and wherein the second end of the rod is positionable in the opening in the second end of second connecting screw. 
   In one aspect, the present invention further comprises a first and second tensioning mechanism, the first tensioning mechanism tensioningly engaging the first end of the rod in the opening in the second end of the first connecting screw and the second tensioning mechanism tensioningly engaging the second end of the rod in the opening in the second end of the second connecting screw. 
   In other aspects, the first and second connecting screws are provided with coupling portions operable to couple the first and second connecting screws with the connecting member. In other aspects, the coupling portions of the first and second connecting screws are further defined as a threaded end of the first and second connecting screws. 
   In other aspects, the threaded end of the first and second connecting screws are connectable to the connecting member by bolts. While in other aspects, the connecting member connected to the first and second connecting screw is sized to retain the first vertebra disposed a distance from the second vertebra. The connecting member may be sized to retain the first vertebra disposed so as to prevent contact with the second vertebra. 
   In other aspects, the first and second pedicle screws are operable to engage a first and second lumbar vertebra, respectively. 
   In yet another aspect the vertebral stabilization assembly further includes a bore screw having a shaft sized similar in diameter to the shaft of the first and second pedicle screw. In one aspect, the diameter of the shaft of the bore screw is substantially similar to the diameter of the shaft of the pedicle screw, while in other aspects the diameter of the shaft of the bore screw is smaller, and in others larger, than the diameter of the shaft of the pedicle screw The bore screw is operative to bore an opening in the vertebra, from the posterior side of the vertebra. 
   The bore screw is useful to create a bore opening in the vertebra that is at a desirable angle in the vertebra. The bore screw may then be located from the anterior side and removed anteriorly according to one aspect or removed posteriorly according to another aspect of the present invention. Where the bore screw is removed anteriorly, the bore screw is provided with an engaging portion on a distal end of the bore screw for connection of the bore screw by a tool for removal from the vertebral anterior. 
   One advantage of utilizing the bore screw is that the angle of placement of the bore screw is known so that the proper pedicle screw may be selected based on the angle of penetration of the bore opening created in the vertebra by the bore screw, such as a pedicle screw having a engaging portion with the proper angle of connection for attachment of the connecting screw and a pedicle screw of appropriate length. 
   In another aspect, the vertebral stabilization assembly of the present invention further includes an indicator positionable posteriorly adjacent the bore opening created by bore screw. The indicator indicating the location of the bore opening from the anterior side of the vertebra. In one aspect, the indicator is an LED (light emitting diode) disposed on a rigid shaft extendable down the bore opening near the anterior side of the vertebra. In other aspects, the shaft may be substantially flexible for easy removal. In other aspects, the indicator is an LED or higher intensity light, such as a laser light, and is disposed posteriorly near the bore opening such that the light projects down the opening and is perceptible from the vertebral anterior. 
   In another aspect the present invention provides a pedicle screw for securing a connecting screw of a vertebral stabilization assembly. The pedicle screw includes a shaft, an engaging portion and coupling portion. The shaft has a threaded portion operable for threading engagement of the pedicle screw with a vertebra. The engaging portion is provided on the shaft and operable to receive a connecting screw of the vertebral stabilization assembly. The coupling portion is provided on the shaft and adapted to connect a guide member of the vertebral stabilization assembly. In one aspect of the pedicle screw of the present invention the shaft is cannulated. The cannulated portion of the shaft further defined as a passageway extending through the shaft from a first end of the shaft to a second end of the shaft. 
   In one aspect, the shaft is further defined as having a first end and a second end such that the threaded portion is adjacent the first end and the second end is operable to receive rotational engagement for rotating the pedicle screw. In yet another aspect, the engaging portion is further defined as an opening on the shaft operable to receive the connecting screw of the vertebral stabilization assembly. 
   In other aspects, the opening is further defined as extending through the shaft from a shaft first side to a shaft second side. In another aspect, the opening is coupleable with the connecting screw to provide stabilizing engagement of the connecting screw. While yet other aspects provide the opening is coupleable with the connecting screw to provide rigid engagement with the connecting screw. 
   In one aspect, the engaging portion is coupleable with the connecting screw to provide locking engagement with the connecting screw. In other aspects, the engaging portion is coupleable with the connecting screw to provide threaded engagement with the connecting screw. In yet other aspects, the coupling portion of the shaft is associated with the opening in the shaft such when the guide member is coupled to the coupling portion an alignment member of the guide member is aligned with the engaging portion in the shaft. 
   In one aspect, the coupling portion is further defined as an opening operable for threading engagement. In another aspect, the shaft is further defined as a substantially rigid shaft constructed from a material selected from the group consisting of steel, aluminum, metallic materials and polymeric materials. While in other aspects, the shaft is substantially cannulated such that a passageway extends through the shaft from a first end of the shaft to a second end of the shaft. In one aspect, the pedicle screw is operable to engage a lumbar vertebra. In another aspect, the pedicle screw is further operable to engage a thoracic vertebra. 
   In one aspect, the engaging portion on the shaft of the pedicle screw includes rotational portion for rotating the engaging portion for receiving the connecting screw at various angles relative to the shaft of the pedicle screw. In some aspects, the rotational portion includes a hinging member or a ratcheting member operative for rotation of the engaging portion. In other aspects, the engaging portion is disposed in an engaging opening in the shaft of the pedicle such that the engaging portion is rotatable within the engaging opening and, in some aspects, becomes fixed or locked when the connecting screw is received by the engaging portion. 
   In one aspect, the shaft of the pedicle screw is provided with at least one non-continuous thread extending circumferentially about the shaft such that at least one gap is disposed between a first portion of the non-continuous thread and a second portion of the non-continuous thread. The advantage of the disposition of the non-continuous thread is that when the nerve is aggravated by the placement of the pedicle screw, the pedicle screw may be rotated into a position such that the gap is adjacent the aggravated nerve instead of the thread to alleviate the aggravation which may be caused by the threaded portion of the shaft of the pedicle screw. 
   In another aspect, the shaft of the pedicle screw is provided with a first threaded portion and a reinforced portion. The reinforced portion of the shaft has a diameter that is greater than a diameter of the first threaded portion of the shaft. In one aspect, the reinforced portion of the shaft is substantially adjacent the engaging portion of the shaft for reinforcing the connection of the connecting screw to the pedicle screw via the engaging portion. 
   In another aspect the reinforced portion of the shaft is adjacent the first threaded portion and adjacent a second threaded portion, the diameter of the reinforced portion is greater than the diameter of the first threaded portion and about equal to a diameter measured from an outermost edge of a plurality of threads provided on the first threaded portion of the shaft. The diameter of the reinforced portion of the shaft is less than a diameter measured from an outermost edge of a plurality of threads provided on the second threaded portion of the shaft. The reinforced portion of the shaft is one advantage of the present aspect since the stability of the vertebral stabilization assembly is significantly enhanced by the additional structural support provided by the reinforced portion for connection of the connecting screw to the engaging portion of the pedicle screw adjacent the reinforced portion. 
   In yet another aspect, the shaft of the pedicle screw has at least a first groove extending a distance along the length of the shaft. In one aspect, a distal end of the shaft of the pedicle screw is substantially conical, while in other aspects, the distal end of the shaft is a substantially flat surface. In one aspect, where the distal end of the shaft is a substantially flat surface, the pedicle screw is provided with a cap which may have a conically shaped first end and a second end configured for mating connection near the distal end of the pedicle screw. In this aspect, the mating connection may be achieved by providing a recess in at least the first groove on the shaft and a notch on an inner surface of the cap such that the notch on the inner surface of the cap is tensioningly received by the recess in at least the first groove of the shaft. 
   In one aspect, the distal end of the pedicle screw is rectangularly configured for mating with a guide member for proper alignment of the engaging portion of the pedicle screw for connection of the connecting screw. In one aspect, only a portion of the shaft is provided with threads. In this aspect, the threads may be provided except on a portion of the shaft substantially adjacent the engaging portion. In other aspects, only a portion of the shaft above the engaging portion is provided with threads, while in other aspects only a portion of the shaft below the engaging portion is provided with threads. 
   In yet another aspect, the pedicle screw has a first end provided with a head operative for rotational engagement of the pedicle screw with the vertebra. A coupling portion is disposed adjacent the first end the pedicle screw and is further operative to engage a guide member of the vertebral stabilization assembly. In this aspect, the pedicle screw is provided for anterior placement such that a distal end of the pedicle screw which initially penetrates the vertebra from an anterior side of the vertebra engages and stabilizes from within the body portion of the vertebra near the pedicle of the vertebra. After placement of the pedicle screw, the head of the pedicle screw is disposed adjacent the anterior side of the vertebra for receiving a guide member. 
   One advantage of the pedicle screw for anterior placement and stabilization is that, when utilizing this aspect of the pedicle screw, placement of the vertebral stabilization assembly may be accomplished entirely from the patient&#39;s anterior eliminating the need to rotate the patient and further reducing the time needed for the surgical procedure. Utilizing the present aspect of the pedicle screw for anterior placement and stabilization provides numerous advantages even where portions of the medical procedure are accomplished from the patient&#39;s posterior. For example, in some aspects, it may be useful and necessary to rotate the patient and perform significant or peripheral procedures from the patient&#39;s posterior during certain portions of the vertebral stabilization procedure. 
   In yet other exemplary embodiments, the present invention provides a tool configured to connect to the distal end of the pedicle screw. In one aspect, the tool is provided with a first end having a handle adapted to be grasped by the hand of an individual and a second end provided with a connector to connect to the distal end of the pedicle screw to retain and stabilize the pedicle screw for placement and removal of the connecting screw. In one aspect the distal end of the pedicle screw is provided with an opening and the second end of the tool is provided with a connector configured to be received into the opening in the distal end of the pedicle screw for securing the pedicle screw. 
   In yet another aspect, the connecting screw is provide with at least a first groove on a shaft portion of the connecting screw for connection by a tool for retaining the connecting screw for placement and removal of the connecting screw. In one aspect, the connecting screw has an opening on one end of the connecting screw, and the tool is provided with a connector adapted to be received by the opening and configured to connect to the tool. 
   In yet another aspect, the present invention provides a guide member for placement of a screw of a vertebral stabilization assembly. The guide member including a coupling portion, and offset member, and an alignment member. The coupling portion is operable to couple with a coupling portion of a pedicle screw of the vertebral stabilization assembly. The offset member is connected to the coupling portion of the guide member. The offset member extending from the coupling portion relative to the connection of the coupling portion of the guide member to the coupling portion of the pedicle screw. The alignment member is connected to the offset member. The alignment member is operable for alignment of the connecting screw of the vertebral stabilization assembly with a portion of the pedicle screw of the vertebral stabilization assembly. 
   In one aspect, the coupling portion of the guide member is operable to couple with the coupling portion of the pedicle screw such that the offset member extends in a predetermined direction relative to the coupling of the coupling portion of the guide member to the coupling portion of the pedicle screw. While in other aspects, the offset member is further provided with a first end and a second end, and wherein the first end of the offset member is connected to the coupling portion and wherein the second end of the offset member is coupled to the alignment member. 
   In one aspect, the offset member is positionable relative to the coupling of the coupling portion with the end portion of the pedicle screw. While in other aspects, the offset member extends from the coupling portion adjacent a shaft portion of the pedicle screw. 
   In one aspect, the coupling portion of the guide member couples to the coupling portion of the pedicle screw such that the offset member positions the alignment member connected to the offset member substantially aligned adjacent a portion of the pedicle screw. In yet another aspect, the alignment member substantially aligns adjacent to the engaging portion of a shaft of the pedicle screw. While yet in other aspects, the alignment member substantially aligns adjacent an opening on the shaft of the pedicle screw. In yet another aspect, the alignment member provides alignment for threadingly taping the vertebra adjacent the opening in the pedicle screw. 
   In one aspect, the alignment member provides alignment for attachment of the connecting screw of the vertebral stabilization assembly to the pedicle screw. In other aspects, the alignment member is further defined as tubular member having a first end, a second end and a opening extending through the tubular member from the first end to the second end. While in yet other aspects, the opening extending through the tubular member is provided with a diameter sufficient to receive the connecting screw of the vertebral stabilization assembly through the opening in the tubular member for alignment with an engaging portion of a shaft of the pedicle screw of the vertebral stabilization assembly. 
   In another aspect, the present invention provides a vertebral stabilization assembly having dual pedicle screws including a first pedicle, a second pedicle screw and a connecting screw. The first pedicle screw has a shaft provided with a threaded portion operable for threading engagement of the first pedicle screw with a first vertebra. The shaft of the first pedicle screw has an engaging portion. 
   The second pedicle screw has a shaft provided with a threaded portion operable for threading engagement of the second pedicle screw with the first vertebra, the shaft of the second pedicle has an engaging portion. The connecting screw has a first end and a shaft, the first end of the connecting screw is adapted to be received by the engaging portion of the first pedicle screw. The shaft of the connecting screw is adapted for connection to the engaging portion of the second pedicle screw. 
   In yet another aspect, the present invention provides a method for stabilizing a lower vertebra and an upper vertebra from an anterior side of the vertebrae using a vertebral stabilization assembly. The method includes inserting a first pedicle screw into the lower vertebra through a pedicle and a vertebral body of the lower vertebra from a posterior side of the lower vertebra. The pedicle screw includes a shaft provided with a threaded portion operable to threadingly engage the lower vertebra. The shaft of the first pedicle screw has an engaging portion operable to receive a first connecting screw. The shaft of the first pedicle screw having a coupling portion operable to couple with a guide member of the vertebral stabilization assembly. 
   The method includes inserting a second pedicle screw into an upper vertebra through a pedicle and a vertebral body of the upper vertebra from a posterior side of the upper vertebra. The second pedicle screw includes a shaft provided with a threaded portion operable to threadingly engage the upper vertebra. The shaft of the second pedicle screw has an engaging portion operable to receive a second connecting screw. The shaft to the second pedicle screw has a coupling portion operable to couple with a guide member of the vertebral stabilization assembly. The method further includes locating the coupling portion of the shaft of the first pedicle screw from an anterior side of the lower vertebra. 
   The method includes coupling the guide member to the coupling portion of the shaft of the first pedicle screw from the anterior side of the lower vertebra. The method further provides for inserting a lower connecting screw through the anterior side of the lower vertebra using the guide member. The lower connecting screw includes a first end adapted to be received by the engaging portion of the first pedicle screw and a second end adapted to reside outside the lower vertebra on an anterior side of the lower vertebra. 
   The method includes locating the coupling portion of the shaft to the second pedicle screw from an anterior side of the upper vertebra. The method provides for coupling the guide member to the coupling portion of the shaft to the second pedicle screw from the anterior side of the upper vertebra. The method further includes inserting an upper connecting screw through the anterior side of the upper vertebra using the guide member. The upper connecting screw includes a first end adapted to be received by the engaging portion of the second pedicle screw and a second end adapted to reside outside the upper vertebra on the anterior side of the upper vertebra. 
   The method also provides for connecting the second end of the lower connecting screw of the lower vertebra to the second end of the upper connecting screw of the upper vertebra. In one aspect, the first and second pedicle screws are posteriorly placed on the right side of the lower and upper vertebra, respectively, and wherein the lower and upper vertebra are further defined as a lower and upper lumbar vertebra. In another aspect, the first and second pedicle screws are posteriorly placed on the right side of the lower and upper vertebra, respectively, and wherein the lower and upper vertebra are further defined as a lower and upper thoracic vertebra. 
   In one aspect, the present invention is directed to a method of anterior vertebral stabilization including placing from the patient&#39;s anterior the pedicle screw such that a portion of the pedicle screw is stabilized in a pedicle portion of the vertebra. 
   In one aspect, the first pedicle screw is further provided with a cannulated shaft having a passageway extending from a first end to a second end of the first pedicle screw and wherein locating the coupling portion of the shaft of the first pedicle screw from the anterior side of the lower vertebra further provides for extending a tool operable to drill through a portion of the lower vertebra through the passageway of the shaft of the first pedicle screw and drilling the portion of the lower vertebra such that the tool extends at least partially through the anterior side of the lower vertebra. 
   In one aspect, the second pedicle screw is further provided with a cannulated shaft having a passageway extending from a first end to a second end of the second pedicle screw and wherein locating the coupling portion of the shaft of the second pedicle screw from the anterior side of the upper vertebra further includes extending the tool operable to drill through a portion of the upper vertebra through the passageway of the shaft of the second pedicle screw and drilling the portion of the upper vertebra such that the tool extends at least partially through the anterior side of the upper vertebra. 
   In other aspects, coupling the guide member to the first and second pedicle screws further includes threadingly coupling the guide member to the coupling portion of the shaft of the first and second pedicle screws. In another aspect, coupling the guide member to the first and second pedicle screws further includes matingly coupling the guide member to the coupling portion of the shaft of the first and second pedicle screws. 
   In one aspect, inserting the lower connecting screw further includes positioning the lower connecting screw in alignment with the engaging portion of the first pedicle screw utilizing an alignment member of the guide member and threading the lower connecting screw through anterior side of the lower vertebra. 
   In one aspect, positioning the lower connecting screw in alignment with the engaging portion of the first pedicle screw further includes receiving the lower connecting screw by the alignment member of the guide member, the guide member adapted to position the alignment member connected thereto the guide member substantially aligned adjacent the engaging portion of the first pedicle screw. 
   In other aspects, inserting the upper connecting screw further includes positioning the upper connecting screw in alignment with the engaging portion of the second pedicle screw utilizing the alignment member of the guide member and threading the upper connecting screw through anterior side of the upper vertebra. 
   In one aspect, positioning the upper connecting screw in alignment with the engaging portion of the second pedicle screw further includes receiving the upper connecting screw by the alignment member of the guide member, the guide member adapted to position the alignment member connected thereto the guide member substantially aligned adjacent the engaging portion of the second pedicle screw. 
   In another aspect, connecting the upper connecting screw to the lower connecting screw further includes, providing a connecting member having a first end and a second end, connecting the second end of the lower connecting screw to the first end of the connecting member and connecting the second end of the upper connecting screw to the second end of the connecting member. 
   In yet another aspect, the connecting member is a plate and wherein the second end of the lower connecting screw receives the first end of the plate and wherein the second end of the upper connecting screw receives the second end of the plate. 
   In yet another aspect, the connecting member is a bracket and wherein the second end of the lower connecting screw receives the first end of the bracket and wherein the second end of the upper connecting screw receives the second end of the bracket. While in other aspects, the connecting member is a rod and wherein the second end of the lower connecting screw connects to the first end of the rod and wherein the second end of the upper connecting screw connects to the second end of the rod. 
   The pedicle screw of the present invention advantageously provides for posterior placement of the pedicle screw through a pedicle portion of the vertebra for secure attachment of the pedicle screw to the vertebra. The cannulated shaft of the pedicle screw is adapted to receive a drill bit there through such that the drill bit may be caused to drill through to the anterior side of the vertebra for easily locating the shaft of the pedicle screw. Another advantage of the present invention is that the pedicle screw is adapted for posterior placement through a pedicle portion of the vertebra for maximum stabilization. The connecting screw of the vertebral stabilization assembly is adapted to engage the engaging portion provided on the shaft of the pedicle screw to further promote a stable engagement of the vertebral stabilization assembly. 
   Yet another advantage of the present invention is that the engagement of the engaging portion of the shaft of the pedicle screw with the connecting screw prevents the pedicle screw or the connecting screw from moving or backing out of the vertebra since the connecting screw and pedicle screw are connected to one another. 
   Another advantage to the present invention is that the added stability of the pedicle screw posteriorly placed and connected to the connecting screw anteriorly insures for maximum stabilization and attachment of the connecting member and thus greater vertebral stabilization. Another advantage to the present invention is that the pedicle screw may be percutaneously placed by making only a small posterior incision and thus overcoming the disadvantages associated with posterior fusion requiring large posterior muscle dissection and the problems associated therewith. For this reason, the present invention is safer for the patient. 
   Anterior stabilization via connection to posteriorly placed pedicle screws has numerous advantages including significantly reducing the total time required for the surgical procedure. Avoidance of the radical muscle dissection required for posterior connection and stabilization is one factor in reducing the time to perform the surgery to about 2.5 hours versus the 5 to 7 hours such a procedures ordinarily requires. Thus, anterior stabilization via connection to posteriorly placed pedicle screws provides numerous advantages over prior vertebral stabilization systems and methods. 
   As well as being placed percutaneously, the pedicle screw may be positioned so that a head of the pedicle screw is substantially flush with the surface bone of the vertebra. Such placement further reduces interference with back muscles and associated problems and presents another advantage according to one aspect of the present invention. 
   Another advantage is that the present invention allows for the drill bit to be disposed within the cannulated portion of the shaft of the pedicle screw for only minor penetration of the surface of the anterior side of the vertebra to avoid the risk of damage to soft tissue adjacent the anterior of the vertebra. 
   Another advantage of the present invention is that the guide member allows for alignment of the connecting screw with the engaging portion of the pedicle screw without the necessity for time-consuming and inaccurate x-rays, MRI&#39;s, or other similar scanning or locating devices. 
   Another advantage of the present invention is that the method provides for placement of the vertebral stabilization assembly on an anterior side of the vertebrae eliminating many of the problems inherent in posterior fusion. Furthermore, elimination of the posterior fusion substantially reduces the amount of time required to perform the stabilization procedure according to the present invention. Another advantage of the present invention is that by posterior placement of the pedicle screw in the pedicle portion of the vertebra and anterior stabilization via the connecting screw, the vertebral stabilization assembly of the present invention provides improved stabilization about a point central to the vertebral body versus about posterior or anterior edges of the vertebra. Thus, the present invention centrally distributes the stabilization pressures, tensions, weight, and stress as opposed to focusing the stabilization pressures about the outer edges of the vertebra. The central stabilization promotes improved stabilization of the vertebrae and improved fusion of the vertebrae. 
   In yet another aspect, the present invention provides a vertebral stabilization assembly having dual pedicle screws for placement in a first vertebra including a first pedicle screw, a second pedicle screw and a connecting screw. The first pedicle screw has a shaft provided with a threaded portion operable for threading engagement of the first pedicle screw with the first vertebra. The shaft of the first pedicle screw has an engaging portion. 
   The second pedicle screw has a shaft provided with a threaded portion operable for threading engagement of the second pedicle screw with the first vertebra, the shaft of the second pedicle screw has an engaging portion. The connecting screw has a first end and a shaft, the first end of the connecting screw is adapted to be received by the engaging portion of the first pedicle screw. The shaft of the connecting screw is adapted for connection to the engaging portion of the second pedicle screw. 
   In one aspect, the engaging portion of the second pedicle screw is defined as a threaded opening operable for the connecting screw to extend through and further operable to secure a portion of the shaft of the connecting screw. 
   In another aspect, a fixation tool is provided for placement of the first and second pedicle screws in the first vertebra so as to align the first and second pedicle screws for connection by the connecting screw. The fixation tool includes a first alignment member disposed adjacent a second alignment member, a third alignment member is offset relative to the first and second alignment members. The first and second alignment members of the fixation tool provide alignment for positioning the first and second-pedicle screws in the vertebra. The third alignment member of the fixation tool aligns the connecting screw for coupling with the first and second pedicle screws. 
   In still another exemplary embodiment, the present invention provides another vertebral stabilization assembly for stabilizing vertebrae. The assembly comprises a first vertebral screw having a shaft with a threaded portion and an engaging portion and a second vertebral screw having a shaft with a threaded portion and an engaging portion. The assembly also comprises a first connecting screw having a first end configured to be engaged by the engaging portion of the first vertebral screw, and a second connecting screw having a first end configured to be engaged by the engaging portion of the second vertebral screw. The assembly further comprises a first horizontal connecting member configured to be coupled to the first vertebral screw and the first connecting screw, and a second horizontal connecting member configured to be coupled to the second vertebral screw and the second connecting screw. The assembly additionally comprises a vertical connecting member configured to be coupled to the first horizontal connecting member and the second horizontal connecting member. 
   Other objects, features, and advantages of the present invention will be apparent to those skilled in the art from the following detailed description when read in conjunction with the accompanying drawings and appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description, wherein like reference numerals represent like parts, in which: 
       FIG. 1  is a perspective view of a vertebral stabilization assembly illustrated partially in phantom and shown stabilizing an upper and lower vertebra according to one aspect of the present invention; 
       FIG. 2  is a perspective view of the vertebral stabilization assembly, as shown in  FIG. 1 , constructive in accordance with the present invention; 
       FIG. 3  is a side view of a connecting member constructed in accordance with one aspect of the present invention; 
       FIG. 3A  is a side view of yet another aspect of the connecting member of the present invention; 
       FIG. 3B  is a side view of one aspect of a connecting screw shown with the connecting member attached to the connecting screw by a nut; 
       FIG. 4  is a side elevational view of a pedicle screw according to one aspect of the present invention; 
       FIG. 5  is a top plan view of the pedicle screw, illustrated in  FIG. 4 , shown posteriorly positioned in a lumbar vertebra in accordance with the present invention; 
       FIG. 6  is a perspective view of a guide member according to one aspect of the present invention for aligning a connecting screw shown in phantom; 
       FIG. 7  illustrates alignment of the connecting screw utilizing the guide member for attachment of the connecting screw to the pedicle screw positioned within the lumbar vertebra, as shown in  FIG. 5 , according to one aspect of the present invention; 
       FIG. 8  illustrates a left side posterior positioning of the pedicle screw and alignment of the connecting screw utilizing the guide member according to yet another aspect of the present invention; 
       FIG. 9  is a top plan view of other aspects of the guide member and the pedicle screw shown connected in accordance with yet another aspect of the present invention; 
       FIG. 10  illustrates alignment of the connecting screw utilizing the guide member, as shown in  FIG. 9 , for attachment of the connecting screw to the pedicle screw positioned within the lumbar vertebra according to one aspect of the present invention; 
       FIG. 11  is a perspective view illustrating yet another aspect of the connection of the pedicle screw with the guide member constructed in accordance with the present invention; 
       FIG. 12  is a flow chart illustrating a method for stabilizing vertebrae from the anterior side of the vertebrae utilizing the vertebral stabilization assembly according to another aspect of the present invention; 
       FIG. 13  is a perspective view illustrating yet another aspect of the pedicle screw provided with a shaft having a reinforced portion; 
       FIG. 14  is a perspective view of another aspect of the pedicle screw illustrating the shaft with at least a first groove and a flat surface on a distal end of the shaft constructed in accordance with the present invention; 
       FIG. 15  is a cross-sectional view of the shaft of the pedicle screw illustrated in  FIG. 14  taken along line  15 - 15  thereof; 
       FIG. 16  is a perspective view of a cap according to one aspect of the present invention for attachment near the distal end of the pedicle screw; 
       FIG. 17  is a perspective view of one aspect of a tool for connection near the distal end of the pedicle screw constructed in accordance with the present invention; and 
       FIG. 18  is a perspective view of yet another aspect of the tool for use with the vertebral stabilization assembly of the present invention shown connecting to the connecting screw; 
       FIG. 19  is a top plan view of a bore screw according to one aspect of the present invention shown obliquely disposed in the vertebra; 
       FIG. 20  is a top plan view of an indicator constructed in accordance with one aspect of the present invention disposed in a bore opening of the vertebra; 
       FIG. 21  is a top plan view of the pedicle screw for anterior placement according to yet another aspect of the present invention shown with a distal end of the pedicle screw anchored in the pedicle portion of the vertebra; 
       FIG. 22  illustrates the guide member of the vertebral stabilization assembly attaching adjacent a head portion of the anteriorly placed pedicle screw according to one aspect of the present invention; 
       FIG. 23  is a top plan view of another aspect of the engaging portion of the pedicle screw of present invention for attachment to the connecting screw at various angles; 
       FIG. 24  is a perspective view of one aspect of the pedicle screw of the provided with non-continuous threads; 
       FIG. 25  is a top view of one aspect of the present invention illustrating placement of dual pedicle screws in the vertebra utilizing a fixation tool; 
       FIG. 26  is a top plan view of one aspect of dual pedicle screws invention illustrated anteriorly placed and connected to the connecting screw; 
       FIG. 27  is a top plan view according to one aspect of the present invention illustrating a connecting screw extending across a vertebra and connected to one or dual pedicle screws; 
       FIG. 28  is a top plan view according to one aspect of the present invention illustrating a vertebral screw extending across a vertebra and connected to a connecting screw; and 
       FIG. 29  is a perspective view of a vertebral stabilization assembly illustrated partially in phantom and shown stabilizing an upper and lower vertebra according to another aspect of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   It should be understood at the outset that although an exemplary implementation of the present invention is illustrated below, the present invention may be implemented using any number of techniques, whether currently known or in existence. The present invention should in no way be limited to the exemplary implementations, drawings, and techniques illustrated below, including the exemplary design and implementation illustrated and described herein. 
     FIG. 1  illustrates one aspect of the vertebral stabilization assembly  10  constructed in accordance with the present invention. The vertebral stabilization assembly  10  is an innovative device for stabilizing a plurality of vertebrae of the spine. The vertebral stabilization assembly  10  includes a first pedicle screw  12  and a second pedicle screw  14 . The first pedicle screw includes a shaft  16  provided with a threaded portion  18 . The threaded portion  18  of the shaft  16  is operable for threading engagement of the first pedicle screw  12  with a first vertebra  20 . The shaft  16  of the pedicle screw  12  further includes an engaging portion  22 . 
   The second pedicle screw  14  is substantially similar to the first pedicle screw  12  in that the second pedicle screw  14  includes a shaft  30  provided with a threaded portion  32 . The threaded portion  32  of the shaft  30  is operable for threading engagement of the second pedicle screw  14  with a second vertebra  34 . The shaft  30  of the second pedicle screw  14  is provided with an engaging portion  36 . 
   The shafts  16  and  30  of the first and second pedicle screws  12  and  14  are of appropriate length to sufficiently anchor the first and second pedicle screws  12  and  14  in the first and second vertebra  20  and  34 , respectively. The threaded portions  18  and  32  of the first and second pedicle screws  12  and  14  may be threads similar to those on ordinary screws and extending a distance from the shafts  16  and  30  sufficient to promote optimum anchoring of the first and second pedicle screws  12  and  14  within the first and second vertebra  20  and  34 , respectively. The first and second pedicle screws  12  and  14  are preferably constructed of a substantially rigid material such as, but not limited to, titanium, steel, metal, metal alloys, polymeric material, or a variety of other substantially rigid materials adapted to promote rigid engagement of the first and second pedicle screws  12  and  14  to the first and second vertebra  20  and  34 , respectively. 
   The vertebral stabilization assembly  10  is further provided with a first connecting screw  40  and a second connecting screw  42 . The first and second connecting screws  40  and  42  may be constructed from substantially rigid materials similar to that of the first and second pedicle screws  12  and  14 , such as, but not limited to, titanium, steel, metal, metal alloys, polymeric material, or a variety of other substantially rigid materials adapted and suitable for these purposes. The first connecting screw  40  has a first end  44  adapted to be received by the engaging portion  22  on the shaft  16  of the first pedicle screw  12 . The second connecting screw  42  has a first end  46  adapted to be received by the engaging portion  36  of the shaft  30  of the second pedicle screw  14 . 
   The vertebral stabilization assembly  10  further includes a connecting member  50  that has a first end  52  and a second end  54 . The first end  52  of the connecting member  50  is coupled to the first connecting screw  40 . The second end  54  of the connecting member  50  is coupled to the second connecting screw  42 . This arrangement enables stabilization of the first vertebra  20  and the second vertebra  34 . 
   The connecting member  50  may be constructed from a variety of substantially rigid materials similar to that of the first and second pedicle screws  12  and  14  such as, but not limited to, titanium, steel, metal, metal alloys, polymeric material, or other substantially rigid materials suitable for stabilization of the first and second vertebra  20  and  34  by coupling to the first and second connecting screws  40  and  42 . 
     FIG. 2  illustrates the vertebral stabilization assembly  10 , substantially as shown in  FIG. 1 , with the first and second vertebra  20  and  34  removed from the illustration for the purpose of further describing the present invention. It can be seen that the first and second pedicle screws  12  and  14  are provided with a head  60  and  62 , respectively. The heads  60  and  62  of the first and second pedicle screws  12  and  14  may be configured to receive a tool, such as, but not limited to, a standard flat or a Phillips-head screw driver, Allen or other wrench connection, or a variety of male to female or female to male temporary interconnections for threadingly engaging the first and second pedicle screws  12  and  14  into the first and second vertebra  20  and  34 . 
   In other embodiments (not shown) the heads  60  and  62  of the first and second pedicle screws  12  and  14  may be configured unlike the head of the standard screw and instead unitarily formed, for example, rectangularly from the shaft  16  and  30  for mating engagement with a unique tool adapted to receive the rectangularly-formed shaft. 
   It will be appreciated that a variety of constructions and configurations of the heads  60  and  62  of the first and second pedicle screws  12  and  14  will readily suggest themselves to one of ordinary skill in the art and may be provided in numerous configurations such that a tool may be attached temporarily to the heads  60  and  62  for imparting a rotation upon the first and second pedicle screws  12  and  14 . 
   In the present illustration, the engaging portion  22 . of  the shaft  16  can be more easily seen as adapted to receive the first end  44  of the first connecting screw  40 . The engaging portion  22  of the shaft  16  may be a threaded opening formed in the shaft  16  of the first pedicle screw  12  and adapted to receive a threaded first end  44  of the first connecting screw  40 . In this manner the first connecting screw  40  threadingly engages the engaging portion  22  to achieve a rigid locking connection between the first pedicle screw  12  and the first connecting screw  40 . 
   In other embodiments (not shown) the engaging portion  22  may be a tension connection opening in the shaft  16  for receiving and engaging in a tensioning fashion the first end  44  of the first connecting screw  40 . In yet other embodiments (not shown) the engaging portion  22  may be a locking assembly adapted to receive the first end  44  of the first connecting screw  40  and lock it into place upon insertion. The locking engagement of the engaging portion  22  may be accomplished in a variety of manners including a keyed design of the engaging portion  22  such that when the first end  44  of the first connecting screw  40  is inserted into the engaging portion  22  it is locked into place upon rotation of the first connecting screw  40 . 
   Yet in other embodiments (not shown), the engaging portion  22  may be a modification to the outer surface of the shaft  16  of the first pedicle screw  12  such that the first end  44  of the first connecting screw  40  may be adapted to receive the engaging portion  22  of the shaft  16  within an opening in the first end  44  of the first connecting screw  40 . In this manner the locking or tensioning mechanism may be retained by the first end  44  of the first connecting screw  40  for engaging the first connecting screw  40  with the first pedicle screw  12 . 
   A number of other connections including spring, ball, or other tensioning connections, as well as, threading, locking, and other mating connections for engaging the first end  44  of the first connecting screw  40  with the engaging portion  22  of the shaft  16  of the first pedicle screw  12  will readily suggest themselves to one of ordinary skill in the art and are within the spirit and scope of the present invention. It will be appreciated that the engaging portion  36  of the shaft  30  of the second pedicle screw  14  may be constructed substantially identical to the engaging portion  22  of the shaft  16  of the first pedicle screw  12 . For purposes of brevity no further discussion of the engaging portion  36  is deemed necessary to enable one of ordinary skill in the art on the variety of means for engaging the first and second connecting screws  40  and  42  with the first and second pedicle screws  12  and  14  in light of the discussion regarding the engaging portion  22  of the first pedicle screw  12 . 
   The first connecting screw  40  is constructed substantially similar to the second connecting screw  42  and for this reason, only the first connecting screw  40  will be discussed and described for purposes of brevity. The first connecting screw  40  is coupled to the connecting member  50  near a second end  64  of the first connecting screw  40 . The coupling of the first connecting screw  40  to the connecting member  50  may be accomplished in a variety of manners such as, as shown in the present illustration, by providing a threaded portion on the second end  64  of the first connecting screw  40 . 
   In this manner, a coupling  70  may be coupled to the second end  64  of the first connecting screw  40  and attached using a standard nut  72  threadingly engaged with the threaded portion  66  of the second end  64  of the first connecting screw  40 . The coupling  70  may be provided with an offset member  74  adapted to receive a rod  76 . The offset member  74  thereby tensions the portion of the rod  76  extending through the offset member  74  for rigid engagement of the rod  76  to the coupling  70 . 
   The tensioning engagement of the rod  76  by the offset member  74  may be accomplished by providing a screw (not shown), or other tension-imparting structure, threaded through the offset member  74  and into contact with the portion of the rod  76  extending through the offset member  74 . The use of the coupling  70  and the rod  76  is a simple and useful design, according to one aspect, of the connecting member  50  for stabilization of the first and second vertebrae  20  and  34  via the first and second connecting screws  40  and  42 . 
   It should be appreciated, however, that the connecting member  50  may be accomplished utilizing a variety of other structural connections to the first and second connecting screws  40  and  42 . For example, in one embodiment (not shown), an opening may extend through the second end  64  of the first connecting screw  40 . The opening of sufficient diameter to receive the rod  76  there through the opening in the second end  64  of the connecting screw  40 . A tensioning connection, such as a screw or a nut may be utilized to tensionally engage the rod  76  to the second end  64  of the first connecting screw  40 . Other configurations of the coupling  70  may be utilized for these purposes and are within the spirit and scope of the present invention and will readily suggest themselves to one of ordinary skill in the art. 
     FIG. 3  illustrates a side view of another aspect of the connecting member  50  of the vertebral stabilization assembly  10  of the present invention. In this aspect the connecting member  50  is a bracket  90  having a first opening  92  and a second opening  94 . The bracket  90 , as with the various aspects of the connecting member  50 , may be constructed from a variety of substantially rigid materials such as titanium, steel, metal or metal alloys, rigid polymeric material and other substantially rigid materials which may be utilized for these purposes. 
   The bracket  90  is a substantially flat plate provided with the first and second openings extending there through for receiving the first and second connecting screws  40  and  42 . In this manner, the second end  64  of the first connecting screw  40  may be cause to extend through the first opening  92  of the bracket  90 . The nut or other similar device  72  can then be threadingly engaged about the threaded portion  66  and caused to rigidly engage the bracket  90  to the second end  64  of the first connecting screw  40 . Similarly, the second opening  94  may be adapted to receive the second connecting screw  42  for attachment thereto. 
   The symmetrical nature of the vertebral stabilization and assembly  10  lends itself to stabilization of a plurality of vertebrae. That is, the first and second pedicle screws  12  and  14  are substantially similar, as are the first and second connecting screws  40  and  42 . Thus, while only first and second pedicle screws  12  and  14  and first and second connecting screws  40  and  42  are shown, the present invention contemplates stabilization of two or more vertebrae and is well suited for these purposes. In other embodiments (not shown) a third, fourth, or more pedicle screws may be utilized for engagement of a third, fourth, or more connecting screws for stabilization of a plurality of vertebrae. As such, the connecting member  50 , or the bracket  90 , shown in  FIG. 3 , will be provided having appropriate length or with the appropriate number of openings to receive each of the connecting screws for stabilizing the desired number of vertebrae. 
   One advantage of the vertebral stabilization assembly  10  of the present invention is that the connecting member fifty, whether utilizing the bracket  90  or the coupling  70  with the rod  76  (see  FIG. 2 ) is adapted for connection on the anterior or front side of the vertebrae. The connecting member  50  according to the present invention has a low profile and thus minimizes the interference with soft tissue within the anterior of the patient. 
   Another advantage of the present invention is that the first pedicle screw  12  engaging the first connecting screw  40  provides for maximum stabilization in the vertebra  20 . As such secure attachment to the vertebra  20  is optimized and greater stabilization can be accomplished by the innovations provided according to the present invention. Furthermore, the first pedicle screw  12  so connected to the first connecting screw  40  has the effect of inhibiting the first pedicle screw  12  from backing out of the vertebra  20 , as well as preventing the first connecting screw  40  from backing out of the vertebra  20  as well. 
     FIG. 3A  illustrates another aspect of the connecting member  50  that is similar to the bracket  90 , illustrated in  FIG. 3 . In this aspect the bracket  90  is provided with a single opening  96  having a first end  97  and a second end  98  extending through the bracket  90 . The opening  96  near the first and second ends  97  and  98  may be provided with a plurality of notches  99  adapted for securely receiving a portion of a screw, such as the second end  64  of the first connecting screw  40 . 
   The bracket  90  is useful where the first connecting screw  40  and the second connecting screw  42  are not substantially aligned vertically. Thus, the notches  99  may be provided so that the first and second connecting screws  40  and  42  may be connected to the bracket  90  at various notches  99  on the first and second ends  97  and  98 , respectively, of the bracket  90  while maintaining the bracket  90  disposed in a substantially vertical manner while the first and second connecting screws  40  and  42  may not be substantially vertical with respect to one another. 
     FIG. 3B  illustrates another aspect of the first connecting screw  40  shown attached to the connecting member  50 , such as the bracket  90 , using a capped bolt  104 . It can be seen that the second end  64  of the first connecting screw  40  is provided with a notch  106  such that the bracket  90  is flush against the notch  106  of the first connecting screw  40  for secure attachment thereto. A capped bolt  104  or other low-profile connectors may be utilized advantageously so as to minimize the interference and contact of the vertebral stabilization assembly  10  of the present invention with any of the soft tissue of the patient. 
     FIG. 4  illustrates another aspect of the present invention of the pedicle screw, such as the pedicle screw  12 , for securing a connecting screw, such as the first connecting screw  40 , of the vertebral stabilization assembly  10  of the present invention. In this aspect the pedicle screw  12 , as well as having the shaft  16  having the threaded portion  18  and the engaging portion  22 , as previously discussed, further includes a coupling portion  100  provided on the shaft  16 . 
   The coupling portion  100  is adapted to connect a guide member (which will be discussed in greater detail with reference to  FIG. 6 ) of the vertebral stabilization assembly. In one aspect the coupling portion  100  may be a threaded portion on the outer surface of the shaft  16  near the distal end  102  of the shaft  16 . The guide member may be threadingly connected to the coupling portion  100  about the distal end  102  of the shaft  16 . In other embodiments, however, the coupling portion may be an opening provided in the distal end  102  of the shaft  16  such that a portion of the guide member may be threadingly received within the opening in the distal end  102  of the shaft  16  for threading engagement therewith the coupling portion  100 . 
   As previously mentioned, the engaging portion  22  of shaft  16  is operable to receive the first connecting screw  40 . The engaging portion  22  in one embodiment may be provided as an opening on the shaft  16  extending completely through the shaft  16 . The purpose of the engaging portion  22 , as previously discussed, is to provide stabilizing engagement of the first connecting screw  40  with the first pedicle screw  12 . As previously discussed, this rigid engagement may be provided in a variety of manners, such as, but not limited to, a locking engagement, a threading engagement, a tensioning or other rigid coupling connection of the first connecting screw  40  with the first pedicle screw  12  about the engaging portion  22 . 
   Referring also to  FIG. 5  a top view of a vertebra  118 , such as a lumbar vertebra, shown with the first pedicle screw  12  set therein. One advantage of the present invention is that the first pedicle screw  12  may be placed through a pedicle  120  on a posterior side  122  of the vertebra  118 . 
   Posterior placement through the pedicle  120  of the vertebra  118  provides optimum stability and anchoring of the first pedicle screw  12  by threading engagement through the most rigid portions of the vertebra  118 . Significant problems arise when the first pedicle screw  12  is not well anchored within the vertebra  118  and alternate placement is then required. Furthermore, stabile anchoring is critical to reduce the likelihood that the first pedicle screw  12  will back out, or come backwards out of its placement, of the vertebra  118 . The illustrated placement of first pedicle screw  12  advantageously overcomes the disadvantages associated with unstable attachment common with anterior vertebral stabilization systems. 
   As previously mentioned, the connecting member  50  is positionable on the anterior side  124  of the vertebra  118 . Thus, the vertebral stabilization assembly  10  of the present invention achieves the advantages of anterior vertebral stabilization, since the connecting member is positioned on the anterior side  124  of the vertebra  118 , while simultaneously achieving the stability associated with posterior procedures. 
   The first pedicle screw  12  may be placed in the vertebra  118 , substantially as shown, percutaneously or through the skin requiring only a small incision, and avoiding the disadvantages associated with large, invasive posterior procedures which require significant interference and dissection of adjacent muscles. 
   In yet another aspect of the present invention the pedicle screw  12  may be provided with a cannulated shaft  16  such that a passageway  110  extends through the shaft  16  from the head  60  to the distal end  102  thereof the shaft  16 . By utilizing the passageway  110  extending through the shaft  16  of the first pedicle screw  12 , a tool (not shown) such as a tap or drill bit may be placed through this cannulated portion of the shaft  16  such that the tool or drill bit enters near the head  60  of the first pedicle screw  12 . The tool is then extended through the passageway  110  towards the distal end  102 . 
   The tool may then be utilized to drill through to the anterior side  124  of the vertebra  118  for location of the distal end  102  of the pedicle screw  12  from the anterior side  124  of the vertebra  118 . Since only a small distance must be drilled, there is minimal risk to soft tissue or blood vessels. Furthermore, once the tool penetrates the anterior side  124  of the vertebra  118 , the surgeon should be able to sense the reduced resistance and friction on the tool. Furthermore, the tool may be provided with stops or a drill bit may be cannulated to prevent extension of the drill beyond the anterior side  124  of the vertebra  118 . 
   In the present embodiment right side  126  placement of the first pedicle screw  12  is preferable to avoid soft tissue injuries to the patient&#39;s anterior caused by penetration of the drill bit through the anterior side  124  of the vertebra  118  via the passageway  110  of the first pedicle screw  12 . Anatomically, fragile soft tissue and blood vessels are positioned adjacent the right side  126  on the anterior side  124  of the vertebra  118 . By using any number of surgical retraction techniques, these blood vessels may be held toward the right side  126  of the anterior side  124  of the vertebra  118 . As such, the right side  126  placement of the first pedicle screw  12  represents the most efficient, as well as safest, placement for utilizing the first pedicle screw  12  in accordance with the present invention. In some instances, however, left side  128  placement of the first pedicle-screw  12  in the vertebra  118  will be necessary. Left side  128  placement of the first pedicle screw  12  will be discussed in greater detail with reference to  FIG. 8 . 
     FIG. 6  illustrates yet another aspect of the present invention of a guide member  150 . The guide member  150  includes a coupling portion  152  an offset member  154  and an alignment member  156 . The coupling portion  152  is operable to couple with the coupling portion  100  of the first pedicle screw  12  (see  FIG. 4 ). The offset member  154  is connected to the coupling portion  152 . The offset member  154  extends from the coupling portion  152  relative to the connection of the coupling portion  152  to the coupling portion  100  of the first pedicle screw  12 . The alignment member  156  is connected to the offset member  154 . The alignment member  156  is operable for alignment of the connecting screw, such as the first connecting screw  40 , with a portion of the first pedicle screw  12 , such as the engaging portion  22 . 
   The guide member  150  may be constructed from a variety of materials such as, but not limited to, titanium, steel, metal or other metal alloys, a substantially rigid polymeric material, aluminum or other substantially rigid materials sufficient for these purposes. The coupling portion  152  is provided with a first end  160  and a second end  162 . The first end  160  of the coupling portion  152  may be threaded for threading engagement to the coupling portion  100  of the first pedicle screw  12 . 
   It should be appreciated, however, that a number of connecting methods may be utilized to accomplish the connection of the first end  160  of the coupling portion  152  to the coupling portion  100  of the first pedicle screw  12 . For example, the first end  160  may be shaped so as to be substantially rectangular or other geometric shape about a portion of the first end  160  such that a similarly geometrically configured opening in the coupling portion  100  in the distal end  102  of the first pedicle screw  12  is adapted to receive the first end  160  of the coupling portion  152 . Other locking or tensioning engagements of the first end  160  of the coupling portion  152  to the coupling portion  100  of the first pedicle screw  12 , as well as a variety of other methods for achieving this attachment, will readily suggest themselves to one of ordinary skill in the art and are within the spirit and scope of the present invention. 
   The second end  162  of the coupling portion  152  is attached to the offset member  154 . The attachment of the coupling portion  152  to the offset member  154  may be of a connecting, such as threading or tensioning or locking connection, or may be accomplished by a welded or bonded connection of the second end  162  of the coupling portion  152  to the offset member  154 . Although welding or bonding engagements of various components of the vertebral stabilization assembly  10  of the present invention are preferable, it should be appreciated that bonding or other gluing or tacking materials may be used for this connection and satisfactory for these purposes. 
   The offset member  154  is shown as a substantially arcuate member extending from the second end  162  of the coupling portion  152  to the alignment member  156 . However, in other embodiments, one of which is described hereinafter, the alignment member  156  may be comprised of a number of foldable or extendable or hinging segments to promote use within the confinements of the patient&#39;s anterior. While the offset member  154  is shown as a substantially rigid arcuate member, a number of other configurations of the offset member  154 , such as a substantially straight member, or a stair-stepped member, as well as the offset member  154  being comprised of several connectable or extendable members are contemplated according to other aspects (not shown) of the present invention. 
   A number of configurations of the offset member  154 , such as formation of a portion of the offset member  154  unitarily with the coupling portion  152  and formation of a remaining portion of the offset member  154  unitarily formed with the alignment member  156  may also be utilized for these purposes. Although the offset member  154  is shown in the preferred aspect, a variety of configurations of the offset member  154  will readily suggest themselves to one of ordinary skill in the art for positioning the alignment member  156  relative to a portion of the first pedicle screw  12  when the coupling portion  152  of the guide member  150  is connected to the coupling portion  100  of the first pedicle screw  12  and are within the spirit and scope of the present invention and will not be discussed in further detail for the purposes of brevity. 
   The alignment member  156  is rigidly connected to the offset member  154  by welding or bonding or other similar means. However, attachment of the alignment member  156  to the offset member  154  may be accomplished by a threading, locking or tensioning engagement and is satisfactory for these purposes. The alignment member  156  is a substantially tubular member having a first end  164  and a second end  166  and an opening  168  extending through from the first end  164  to the second end  166 . 
   The alignment member  156  is provided such that the opening  168  is of a sufficient diameter to receive a drilling device  170 , shown in phantom, through the opening  168  for alignment with the engaging portion  22  on the shaft  16  of the first pedicle screw  12 . The drilling device  170  may be the a bit of a drill or other devices operative to drill an opening into vertebral bone. Thus, the alignment member  156  receives the drilling device  170  that drills an opening properly aligned for attachment of the first connecting screw  40  to the first pedicle screw  12 . Thus, the guide member  150  is advantageously provided for creating an opening aligned with the engaging portion  22  of the first pedicle screw  12 . 
   It should be appreciated that while the alignment member  156  of the present aspect is illustrated as a substantially tubular member having an opening  168 , other embodiments the alignment member  156  may not be a completely tubular, and instead, be provided as a guide or positioning member for alignment of the first connecting screw  40  with the engaging portion  22  of the first pedicle screw  12 . 
   Numerous configurations for aligning the first connecting screw  40  with the engaging portion  22  of the first pedicle screw  12  may be utilized for these purposes and will readily suggest themselves to one of ordinary skill in the art and are within the spirit and scope of the present invention and will not be discussed further for purposes of brevity. 
     FIG. 7  illustrates a top view of the vertebra  118  shown with the first pedicle screw  12  positioned therein with the guide member  150  shown attached to the first pedicle screw  12 . In this view, it can be seen that the guide member  150  is a useful tool for placement of the first connecting screw  40  for attachment to the engaging portion  22  of the first pedicle screw  12 . It will be appreciated that, procedurally, the first pedicle screw  12  has been percutaneously placed through the posterior side  122  of the vertebra  118 . Thereafter the tool, such as the drill, as previously discussed, is caused to drill through the anterior side  124  of the vertebra  118  thus locating the position of the coupling portion  100  on the distal end  102  of the first pedicle screw  12 . 
   At this point, the guide member  150  may be positioned such that the coupling portion  152  extends through the drilled opening on the anterior side  124  of the vertebra  118 . The coupling portion  152  of the guide member  150  is then connected to the coupling portion  100  of the first pedicle screw  12 . An innovative aspect of the pedicle screw  12  is that the coupling portion  100  on the distal end  102  of the first pedicle screw  12  is associated with the engaging portion  22  on the shaft  16  of the first pedicle screw  12 . The association of the coupling portion  100  and engaging portion  22  of the first pedicle screw  12  is a significant advantage of the first pedicle screw  12  according to the present invention. That is, this association allows for the guide member  150  to be configured relative to this association. Thus, the coupling portion  152  of the guide member  150 , when coupled to the first pedicle screw  12 , aligns the alignment member  156  with the engaging portion  22  on the shaft  16  of the first pedicle screw  12 . Utilizing the guide member  150 , several methods exist for aligning and securing the first connecting screw  40  to the first pedicle screw  12 . It may be preferable to utilize the drilling device  170  to create an opening in the anterior side  124  of the vertebra  118 . Thereafter, the guide member  150  may be removed and the first connecting screw  40  disposed through the opening drilled in the vertebra  118  and connected to the first pedicle screw  12 . 
   In some instances, it may be beneficial for the alignment member  156  to be adapted to receive the first connecting screw  40  positioned to extend through the opening  168  of the alignment member  156 . The first connecting screw  40  may then be drilled or threaded directly into the left side  128  of the anterior side  124  of the vertebra  118 . Whether an opening is first drilled or the first connecting screw  40  is directly drilled into the vertebra  118 , the unique configuration of the guide member  150  relative to the first pedicle screw  12  insures that the first connecting screw  40  will be properly aligned so as to locate the engaging portion  22  of the first pedicle screw  12  for engaging attachment thereto. 
   Thus, another advantage of the guide member  150  of the present invention is that the coupling portion  152  of the guide member  150  is operable to couple with the coupling portion  100  of the first pedicle screw  12  such that the offset member  154  extends in a predetermined direction relative to the coupling of the coupling portion  152  of the guide member  150  to the coupling portion  100  of the first pedicle screw  12 . The offset member  154  of the guide member  150  is positionable relative to the coupling of the coupling portion  152  of the guide member  150  with the coupling portion  100  of the first pedicle screw  12 . 
   It will be appreciated that the connection of the coupling portion  152  of the guide member  150  to the coupling portion  100  of the first pedicle screw  12  must be a locking or fitted type connection such that the offset member  154  properly extends in the proper direction to position the alignment member  156  for alignment with the engaging portion  22  of the first pedicle screw  12 . Achieving the accuracy necessary to locate the engaging portion  22  of the first pedicle screw  12 , which will not be visible since the first pedicle screw  12  will be embedded within the vertebra  118 , is preferably accomplished through the accurate coupling connection of the coupling portion  152  of the guide member  150  to the coupling portion  100  of the first pedicle screw  12 . 
   It should be understood, however, that a number of other methods of locating the engaging portion  22  of the first pedicle screw  12  for alignment with the first connecting screw  40  may be utilized. For example, providing indicia or markings on the head  60  of the first pedicle screw  12  indicating the relative position of the engaging portion  22  of the first pedicle screw  12 . The coupling portion  152  may further include an extension (not shown) extendable through the passageway  110  of the shaft  16  of the first pedicle screw  12 . The extension of the coupling portion  152  of the guide member  150  similarly provided with indicia, markings, or an alignment with the indicia provided on the head  60  of the first pedicle screw  12 . In this manner, when the indicia are aligned, so is the alignment member  156  aligned with the engaging portion  22  on the first pedicle screw  12 . 
   A variety of other methods for obtaining this positioning and alignment for connecting the first connecting screw  40  to the first pedicle screw  12  will readily suggest themselves to one of ordinary skill in the art and are within the spirit and scope of the present invention and will not be discussed for purposes of brevity. 
     FIG. 8  illustrates an alternative left side  128  placement of the first pedicle screw  12  in the vertebra  118 . Procedurally, numerous methods may be utilized to determine whether the first pedicle screw  12  is satisfactorily stabilized within the vertebra  118 , including electrical stimulation to test for a desired threshold. In certain circumstances, such as when the right side  126  placement of the first pedicle screw  12  is ineffective to achieve the desired or required stability, left side  128  placement of the first pedicle screw  12  may be necessary. In this instance, the present invention may be utilized in substantially the same manner for left side  128  placement. 
   The significant difference between the first pedicle screw  12  utilized for right side  126  placement, as opposed to left side  128  placement, is an angle  176  of the engaging portion  22  of the first pedicle screw  12  relative to an axis extending centrally through the shaft  16 , such as the passageway  110  of the first pedicle screw  12 . It can be seen that the angle  176  of the engaging portion  22  of the first pedicle screw  12  necessary for placement of the first connecting screw  40  about the left side  128  of the anterior side  124  of the vertebra  118  varies considerably depending upon whether the first pedicle screw  12  is connected from the left side  128  or the right side  126  of the vertebra  118 . For this reason, a unique first pedicle screw  12  and guide member  150  will be constructed for the left side  128  versus right side  126  placement, such that the guide member  150 , when connected to the first pedicle screw  12 , properly aligns the first connecting screw  40  based upon which vertebral placement, and corresponding first pedicle screw  12  is utilized. 
     FIG. 9  illustrates another aspect of the first pedicle screw  12  as well as another aspect of the guide member  150 . The vertebra  118  is shown having a midline  178  extending from the anterior side  124  to the posterior side  122  of the vertebra  118 . The coupling portion  152  of the guide member  150  is shown connected to the first pedicle screw  12  on the left side  128  of the vertebra  118  adjacent the midline  178 . As previously discussed, placement of the first pedicle screw  12  on the left  128  anterior side  124  of the vertebra  118  may be preferable. 
   In this aspect the guide member  150  is shown having a substantially non-arcuate offset member  154  such that the alignment member  156  extends angularly therefrom the offset member  154 . The coupling portion  152  is shown as a substantially tubular member having a channel  180  extending through the coupling portion  152 . The coupling portion  152  is provided with a recess  182  extending into the channel  180  near the first end  160  of the coupling portion  152 . Furthermore, in this aspect, the first end  160  of the coupling portion  152  is adapted to matingly receive the first pedicle screw  12  near the distal end  102  thereof. As previously discussed, the first pedicle screw  12  is provided with a coupling portion  100  provided, in this aspect, as an opening in the distal end  102  of the first pedicle screw  12 . 
   A locking screw  184  may be extended through the channel  180  from the second end  162  toward the first end  160  of the coupling portion  152 . The locking screw  184  is provided with a head  186  having a larger diameter than that of a shaft  188  portion of the locking screw  184 . The first end  160  of the coupling portion  152  is matingly connectable to the distal end  102  of the first pedicle screw  12 . The locking screw  184  is positioned through the channel  180  until the shaft  188  portion of the locking screw  184  couples with the coupling portion  100  of the first pedicle screw  12 . 
   A tool (not shown) having any standard screw driver or hex, octagonal-type or other connection, for example, may be extended down the channel  180  and used to connect the locking screw  184  to the coupling portion  100  of the first pedicle screw  12 . The locking screw  184  may be threadingly screwed into engagement with the first pedicle screw  12  or connected in other manners which are well known and will readily suggest themselves to one of ordinary skill in the art. 
   In this manner, the head  186  of the locking screw  184  engages the recess  182  within the channel  180  of the coupling portion  152  thereby engaging the coupling portion  152  to the first pedicle screw  12 . It will be appreciated that the locking screw  184 , the coupling portion  152  and the guide member  150  may be provided with indicia or markings to indicate locking engagement and alignment with both the first pedicle screw  12  and the vertebra  118  since it is critical that the locking screw  184  couple the coupling portion  152  to the first pedicle screw  12  at a particular position relative to the vertebra  118 . The indicia or markings may include cross-hair lines, a single line or mark, an arrow, or other markings indicating a rotational position desired for achieving this connection and location. 
   Such accurate positioning may be accomplished based on the threads of the shaft  188  of the locking screw  184  corresponding to threaded openings within the coupling portion  100  of the first pedicle screw  12 . A variety of different structural attachments for obtaining this locking connection for alignment of the guide member  150  with the first pedicle screw  12  such that the alignment member  156  is substantially aligned with the engaging portion  22  on the shaft  16  of the first pedicle screw  12  may be utilized and are within the spirit and scope of the present invention and will readily suggest themselves to one of ordinary skill in the art. 
     FIG. 10  illustrates the first pedicle screw  12  placed from the right side  126  on the posterior side  122  of the vertebra  118 . It will be appreciated that the exact placement and size of the first pedicle screw  12  relative to the vertebra  118 , as shown and disclosed, herein may be enlarged or reduced proportionately depending upon the characteristics of the vertebra  118  and the goals of the vertebral stabilization assembly  10 . However, the first pedicle screw  12  is preferably secured in the pedicle portion of the vertebra  118  such that the distal end  102  of the first pedicle screw  12  is coupleable to the guide member  150  on the left side  128  on the anterior side  124  adjacent the midline  178  of the vertebra  118 . 
   In some aspects, the guide member  150  may be provided with a rotational coupling  190  such as a recess or opening in the offset member  154  of the guide member  150 . The rotational coupling  190  may be adapted as an opening to receive a tool or device for obtaining leverage on the guide member  150  for rotation of the guide member  150 . It will be appreciated that while the first pedicle screw  12  may be provided with indicia or other markings on the head  60  of the first pedicle screw  12  for determining the location and disposition of the engaging portion  22  of the first pedicle screw  12 , a surgeon may have difficulty determining from the posterior side  122  of the vertebra  118  the optimum location for placement of the connecting screw, such as the first connecting screw  40 . 
   Once the patient has been rotated and the guide member  150  connected to the first pedicle screw  12  on the anterior side  124  of the vertebra  118 , only then will the surgeon be able to determine the preferable placement of the first connecting screw  40  relative to the body of the vertebra  118 . In the event the first pedicle screw  12  is not aligned preferably for the first connecting screw  40 , by use of the rotational coupling  190 , such as with a tool connected thereto, the surgeon may rotate the guide member  150  and the first pedicle screw  12  rigidly connected thereto, via the locking screw  184 , to obtain the optimum placement of the first connecting screw  40  into a desired point in the body of the vertebra  118 . In other embodiments, the guide member  150  may not include the rotational coupling  190  and, as such, this rotational alignment may be achieved by grasping and rotating the offset member  154  or other portions of the guide member  150 . 
   Once this optimum positioning has been obtained by rotation using the rotational coupling  190  the tool coupled to the rotational coupling  190  may be removed and a drill or other tool may be utilized and aligned via the alignment member  156  for drilling an opening into the body of the vertebra  118  at the desired location. Thereafter, the locking screw  184  and a guide member  150  may be removed for connection of the first connecting screw  40  to the engaging portion  22  of the first pedicle screw  12 . 
   It will be appreciated that the locking screw  184  may be connected in a variety of manners to the coupling portion  152  of the guide member  150  to obtain a corresponding rotation of the guide member  150  with the first pedicle screw  12  for these rotational purposes which will readily suggest themselves to one of ordinary skill in the art and are within the spirit and scope of the present invention. 
     FIG. 11  illustrates another aspect of the connection of the first pedicle screw  12  to the coupling portion  152  of the guide member  150 . As previously discussed above, a variety of methods exist for connecting the coupling portion  152  with the coupling portion  100  of the first pedicle screw  12 . In the present aspect illustrated in  FIG. 11 , the coupling portion  100  of the first pedicle screw  12  is a substantially rectangular member extending therefrom the shaft  16  of the first pedicle screw  12 . 
   The coupling portion  152  of the guide member  150 , in the present aspect, is provided with a substantially rectangular opening  196  in the first end  160  of the coupling portion  152 . The substantially rectangular opening  196  is sized to matingly receive the rectangular coupling portion  100  to achieve a fitted coupling there between. In this aspect, the coupling portion  100  may be provided with a threaded opening  198  on the distal end  102  of the first pedicle screw  12 . In this manner, the channel  180  extending there through the coupling portion  152  may be provided to guide a connecting member, such as the locking screw  184  or other engaging structure, to be threadingly received by the threaded opening  198  in the distal end  102  of the first pedicle screw  12 . 
   In this manner, the combination of the locking mechanism, such as the locking screw  184 , as well as the rectangular configuration of the coupling portion  100  of the first pedicle screw  12  with the substantially rectangular opening  196  in the first end  160  of the coupling portion  152  promotes an accurately engaged connection of the guide member  150  with the first pedicle screw  12 . It should be appreciated that in other aspects the threaded opening  198  and the channel  180  may be eliminated and only the mating connection of the rectangular coupling portion  100  of the first pedicle screw  12  with the substantially rectangular opening  196  of the coupling portion  152  will be sufficient for this connection. 
   It will be appreciated that the configuration illustrated in the current aspect promotes a sufficient engagement of the guide member  150  to the first pedicle screw  12  to achieve engaging rotation of the first pedicle screw  12  by the guide member  150  when such adjustment for alignment purposes of the first pedicle screw  12  is desirous. It should be appreciated that while the coupling portion  100  of the current aspect is shown as substantially rectangular in configuration as is the substantially rectangular opening  196  of the coupling portion  152  of the guide member  150 , a variety of other configurations such as, but not limited to, triangular configurations, will readily suggest themselves to one of ordinary skill in the art and are within the spirit and scope of the present invention, as are a variety of other coupling connections between the coupling portion  152  and the first pedicle screw  12  which may be utilized to achieve these purposes. 
     FIG. 12  is a flow chart illustrating a method  200  for stabilizing an upper and lower vertebra  118 A and  118 B, substantially similar to the vertebra  118  illustrated in  FIGS. 5 and 7 , from an anterior side  124  of the vertebra  118 A and  118 B using the vertebral stabilization assembly  10  in accordance with the present invention. The method includes, at a block  202 , inserting the first pedicle screw  12  into the lower vertebra  118 B through the pedicle  120  and into the body of the lower vertebra  118 B from a posterior side  122  of the lower vertebra  118 B. The first pedicle screw, as previously described above, includes the shaft  16  provided with the threaded portion  18  operable to threadingly engage the lower vertebra  118 B. The shaft  16  of the first pedicle screw  12  is provided with the engaging portion  22  that is operable to receive the first connecting screw  40 . The shaft  16  of the first pedicle screw  12  further has the coupling portion  100  that is operable to couple with the guide member  150 . 
   The method further includes, at a block  204 , inserting a second pedicle screw  14  into the upper vertebra  118 A through the pedicle  120  and vertebral body of the upper vertebra  118 A from the posterior side  122  of the upper vertebra  118 A. The second pedicle screw  14  including the shaft  30  provided with the threaded portion  32  operable to threadingly engage the upper vertebra  118 A. The shaft  30  of the second pedicle screw  14  provided with an engaging portion  36  operable to receive the second connecting screw  42 . The shaft  30  of the second pedicle screw  14  having a coupling portion  100 , substantially similar to the coupling portion  100  of the first pedicle screw  12 , to couple with the guide member  150 . 
   The first and second pedicle screws  12  and  14  are preferably placed on the posterior side  122  on the right side  126  of the upper and lower vertebra  118 A and  118 B, respectively. It will be appreciated that in one aspect the present invention may be utilized preferably with respect to the lumbar vertebra, while in other embodiments the present invention may be preferably utilized with regard to the thoracic vertebra. 
   At a block  206 , the method includes locating the coupling portion  100  of the shaft  16  of the first pedicle screw  12  from the anterior side  124  of the lower vertebra  118 B. As previously discussed, in one aspect the pedicle screw  12  of the present invention may be provided with the cannulated shaft  16  having the passageway  110  extending through the shaft  16  of the first pedicle screw  12 . In this aspect a tool, such as a drill operable to drill through a portion of the lower vertebra  118 B, may be extended through the passageway  110  of the shaft  16  of the first pedicle screw  12 . The tool may be used to drill through a portion of the lower vertebra  118 B such that the tool extends partially through the anterior side  124  at the lower vertebra  118 B. Similarly, the second pedicle screw  14  may be similarly provided with the passageway  110  for passing the tool there through to drill through a portion of the upper vertebra  118 A such that the drill extends at least partially through the anterior side  124  of the upper vertebra  118 A. 
   At a block  208  the method includes coupling the guide member  150  to the coupling portion  100  of the shaft  16  of the first pedicle screw  12  from the anterior side  124  of the lower vertebra  118 B. In one aspect the coupling of the guide member may be more readily accomplished after an opening has been drilled through to the anterior side  124  of the lower vertebra  118 B. The method further includes, at a block  210 , inserting the lower connecting screw, such as the first connecting screw  40 , through the anterior side  124  of the lower vertebra  118 B using the guide member  150 . As previously discussed, the guide member is a useful tool for aligning the alignment member  156  of the guide member  150  and correspondingly the first connecting screw  40  with the engaging portion  22  of the first pedicle screw  12 . 
   The method further provides, at a block  212 , locating the coupling portion  100  of the shaft  30  of the second pedicle screw  14  from the anterior side  124  of the upper vertebra  118 A. The method further provides, at a block  214 , for coupling the guide member  150  to the coupling portion  100  of the shaft  30  of the second pedicle screw  16  from the anterior side  124  of the upper vertebra  118 A. 
   At a block  216 , the method includes inserting an upper connecting screw, such as the second connecting screw  42  through the anterior side  124  of the upper vertebra  118 A utilizing the guide member  150  for proper alignment. The method also provides, at a block  218 , for connecting the upper and lower connecting screws, such as the first and second connecting screws  40  and  42 , to the connecting member  50  for stabilization of the upper and lower vertebra  118 A and  118 B. 
     FIG. 13  illustrates another aspect of the first pedicle screw  12  having a reinforced portion  230  provided on the shaft  16 . The reinforced portion  230  of the shaft  16  provides additional structural stability for connection of the connecting screw, such as the first connecting screw  40 , to the engaging portion  22  to ensure a rigid and stable connection of the first connecting screw  40  to the first pedicle screw  12 . The reinforced portion  230  is shown having a diameter  232  that is greater than a diameter  234  of a first threaded portion  236  of the shaft  16 . In this manner, it is readily apparent that the reinforced portion  230  having a greater diameter  232  will provide additional structural stability and support for connection of the first connecting screw  40  with respect to the smaller diameter  234  of the first threaded portion  236  of the shaft  16 . The first threaded portion  236  of the shaft  16  is provided with a plurality of threads  238  connected to and extending from the shaft  16  of the first pedicle screw  12 . It can be seen that the diameter  232  of the reinforced portion  230  is about equal to a diameter  240  measured from an outermost edge of the plurality of threads  238  of the first threaded portion  236 . 
   As the first pedicle screw  12  is threadingly engaged into the pedicle portion of the vertebra, such as the first vertebra  20 , the first threaded portion  236  will threadingly engage and retain the first pedicle screw  12  within the first vertebra  20 . In the present embodiment the reinforced portion  230  is not provided with threads, however, in other embodiments the reinforced portion may be provided with threads similar to the plurality of threads  238  or threads extending less far from the reinforced portion  230  than the plurality of threads  238  extend from the first threaded portion  236  of the shaft  16 . In one aspect, the diameter  232  of the reinforced portion  230  is about 6.5 millimeters. However, in other embodiments the diameter  232  of the reinforced portion  230  may be greater or less than 6.5 millimeters as may be necessary to properly engage the shaft  16  of the first pedicle screw  12  in the first vertebra  20 . 
   The shaft  16  of the first pedicle screw  12  is further provided with a second threaded portion  242  having a plurality of threads  244  for engaging the first vertebra  20 . In the present aspect, the diameter  232  of the reinforced portion  230  is less than the diameter  246  measured from an outermost edge of the plurality of threads  244  provided on the second threaded portion  242 . As the first pedicle screw  12 , of the present aspect, is engaged into the first vertebra  20 , the first threaded portion  236  will threadingly engage the pedicle portion and thereafter an interior vertebral body portion of the first vertebra  20 . As the reinforced portion  230  of the first pedicle screw  12  follows behind the first threaded portion  236 , the reinforced portion  230  may have the affect of smoothing the threading engagement within the vertebral body. For this reason, it may be advantageous to provide the plurality of threads  244  having a greater diameter  246  for providing additional threading engagement of the first pedicle screw. In other aspects (not shown) frictional engaging surface structure, such as small or low profile threads, may be provided on the reinforced portion  230  for frictionally engaging the inner vertebral body at the first vertebra  20 . 
   In the present aspect, the diameter  246  of the plurality of threads  244  may be about 7.0 millimeters to achieve additional threading engagement of the second threaded portion  242  of the shaft  16  for stable engagement of the first pedicle screw  12  within the first vertebra  20 . It will be appreciated, however, that in other aspects (not shown) the diameter  246  of the plurality of threads  244  may be of larger or smaller diameter or may be of a similar or smaller diameter than the diameter  232  of the reinforced portion  230  and be adequate for these purposes. Furthermore, in other aspects (not shown) the diameter  234  of the first threaded portion  236  of the shaft  16  may be the same or larger diameter than that of the diameter  232  of the reinforced portion  230 . The reinforced portion  230  of the shaft  16  provides significant additional structural stability for connection of the first connecting screw  40  to the first pedicle screw  12  via the engaging portion  22 . While the length of the reinforced portion  230  relative to the length of the entire shaft  16  of the first pedicle screw  12  is shown in relative proportion according to the present aspect, the reinforced portion  230 , according to other aspects (not shown), may be of significantly greater length and diameter or having a smaller length and diameter relative to the shaft  16  of the first pedicle screw  12  and are within the spirit and scope of the present invention as disclosed and described herein. 
     FIG. 14  illustrates a perspective view of another aspect of the pedicle screw  12  wherein the shaft  16  is provided with at least a first groove  250  extending a distance along the shaft  16  of the first pedicle screw  12 . In the present aspect, a plurality of grooves  250  are shown adjacent a plurality of raised threaded portions  252 . The raised threaded portions  252  are provided for threadingly engaging the first vertebra  20  for securing the first pedicle screw  12  to the first vertebra  20 . The one or more grooves  250  are provided for engaging the first pedicle screw  12  by a tool which will be discussed in greater detail hereinafter with respect to  FIGS. 17 and 18 . In certain circumstances it may be useful or necessary to rigidly retain the first pedicle screw  12  from the anterior side of the first vertebra  20 , such as when connecting the first connecting screw  40  to the first pedicle screw  12 . The one or more grooves  250  provided on the shaft  16  promotes engagement of the first pedicle screw  12  by a tool near the distal end  102  of the shaft  16 . 
     FIG. 15  illustrates a cross section of the first pedicle screw  12  illustrated in  FIG. 14  taken along a line  15 - 15  thereof. In this view, the one or more grooves  250  provided on the shaft  16  of the first pedicle screw  12  can be seen with respect to their relationship to the raised threaded portions  252 . This configuration is useful for promoting engagement of a tool for connecting near the distal end  102  of the first pedicle screw  12 . Although the grooves  250  are shown as generally rounded in configuration extending a distance along the length of the shaft  16  it will be appreciated that in other embodiments (not shown) the grooves  250  may be angular, such as rectangular or triangular in configuration, and having a wider or narrower width  254  which are within the spirit and scope of the present invention as disclosed and described herein. 
   In this view, it can be seen that a number of grooves  250  such as two or four grooves  250  may promote improved engagement by a tool of the first pedicle screw  12  near the distal end  102 , however, any number of grooves  250  may be utilized and are within the spirit and scope of the present invention. 
   It will be appreciated that the configuration of the first pedicle screw  12  illustrated having one or more grooves  250  extending a distance along the length of the shaft  16  may also be utilized with respect to the configuration of the first and second connecting screws  40  and  42 . In this manner, a tool may be utilized to connect to the second end  64  of the first connecting screw  40  for inserting the first connecting screw  40  into the engaging portion  22  of the first pedicle screw  12 , as well as for removal of the first connecting screw  40  from the engaging portion  22  of the first pedicle screw  12 . 
   From time to time it may be necessary to remove portions of the vertebral stabilization assembly  10  of the present invention from the patient and it will become necessary for the first connecting screw  40  and the first pedicle screw  12  to be configured so as to be easily removable. It will be appreciated that metal tightly connected frequently galls or becomes frozen. In this manner, configuration of the first pedicle screw  12  and the first connecting screw  40  having, for example, grooves  250  and other similar configurations, as previously discussed, and utilization of a tool adapted to engage the grooves  250  along the shaft  16  of the first pedicle screw  12 , for example, will be beneficial for obtaining the necessary leverage for installation and removal purposes. 
     FIG. 16  illustrates a cap  260  configured to be connected near the distal end  102  of the first pedicle screw  12 . The cap  260  may be constructed from a variety of materials, such as a rigid or non-rigid plastic or polymeric material, metallic or other materials adapted for connection to the first pedicle screw  12  for penetration through the body of the first vertebra  20 . In the present aspect it can be seen that the first end  262  of the cap  260  is substantially conically shaped for promoting penetration of the first pedicle screw  12  through the first vertebra  20 . The cap  260  is advantageously provided where the first pedicle screw  12  is provided with a flat surface  264  on the distal end  102  of the first pedicle screw  12  (see  FIG. 14 ). 
   A flat surface  264  on the distal end  102  of the first pedicle screw  12  further promotes connection and engagement of a tool to the first pedicle screw  12  for purposes which will be discussed hereinafter. In this aspect, the cap  260  will be necessary to reduce or minimize any damage or aggravation caused by placement of the pedicle screw to any nerves or tissue in or about the area of the first vertebra  20 , such as nerves positioned near the pedicle portion of the first vertebra  20 . 
   The cap  260  is shown as a substantially conical member having an inner surface  266  that is provided with one or more notches  268  provided on the inner surface  266  of the cap  260 . The notches  268  may be configured to be tensioningly received by a recess  270  which may be provided on the shaft  16  of the first pedicle screw  12  as shown in  FIG. 14 . In this manner, the notches  268  may be tensioningly received by one or more recesses.  270  on the shaft  16  which retains the cap  260  sufficiently engaged near the distal end  102  of the first pedicle screw  12 , as well as promoting easy removal of the cap  260  from the first pedicle screw  12 . The cap  260  may then be easily removed after placement of the first pedicle screw  12  for attachment of the guide member  150 , as well as a tool for retaining and stabilizing the first pedicle screw  12  near the distal end  102  of the first pedicle screw  12 . 
     FIG. 17  illustrates a tool  280  constructed in accordance with one aspect of the present invention for stabilization of the first pedicle screw  12  and the connecting screws, such as the first connecting screw  40 . The tool  280  is provided with a first end  282  having a handle  284  adapted to be grasped by the hand of an individual. The tool  280  is provided with a shaft  286  extending from the first end to a second end  288 . The shaft  286  may be of sufficient length to easily utilize the tool  280  for connection and removal of the vertebral stabilization assembly  10  during the surgical process. 
   A connector  290  is provided on the second end  288  of the tool  280  and configured so as to receive, for example, the shaft  16  of the first pedicle screw  12  provided with one or more grooves  250  on the shaft  16 . In this manner, the connector  290  is provided with mating notches  292  adapted to be received by the grooves  250  on the shaft  16  of the first pedicle screw  12 . 
   Once positioned near the distal end  102  of the first pedicle screw  12 , the mating notches  292  will receive and engage the first pedicle screw  12  so that the tool  280 , when rotated by the individual, will have the affect of rotating the first pedicle screw  12 , or, as previously discussed, for stabilizing and retaining the first pedicle screw  12  while removing or installing the connecting screws, such as the first connecting screw  40 . As previously discussed, it may be necessary to utilize the tool  280  to stabilize the first pedicle screw  12 , particularly when attempting to remove the rigid connection of the first connecting screw  40 . 
   During the removal of the vertebral stabilization assembly  10 , the first connecting screw  40  will likely be rigidly engaged in the engaging portion  22  of the first pedicle screw  12 . When utilizing a first tool, such as the tool  280 , to connect to for removal of the first connecting screw  40 , it may be necessary to utilize a second tool, such as the tool  280 , to engage the distal end  102  of the first pedicle screw  12  to retain the first pedicle screw  12  while removing the first connecting screw  40 . Utilization of one or more of the tools  280  may be beneficial while installing, as well as removing the vertebral stabilization assembly  10 . 
   Furthermore, it will be appreciated that in other aspects the connector  290  may be provided on an electric or pneumatic device such as a drill or other apparatus. 
     FIG. 18  illustrates another aspect of the tool  280  and a different aspect of the handle  284  as well as the connector  290 . In this view, the handle  284  is more easily grasped by a single hand, such as the handle of a common screw driver, and the connector  290  is configured with a plurality of flat surfaces  294 , such as ordinarily found in a wrench-wrench. In this manner, the first connecting screw  40  may be provided with an opening  296  configured to receive the connector  290  for engagement of the tool  280  with the first connecting screw  40 . 
   A number of configurations of the opening  296  on the second end  64  may be utilized such as one or more grooves  250 , and may be provided with associated tools, such as the tool  280  to establish a rigid engagement of the tool  280  to the connecting screw, such as the first connecting screw  40 , and the first pedicle screw  12 . It is within the scope of the present invention that the various configurations of the first pedicle screw  12  and the first connecting screw  40  may be interchanged along with the configurations of the tool  280  to promote maximum utility for installation and removal of the vertebral stabilization assembly. For example, the grooves  250  may be provided on the shaft  16  of the first pedicle screw  12 , substantially as shown with respect to  FIGS. 14 and 15 , while the first connecting screw  40  may be provided with a wrench wrench-type opening  296  or vice versa. 
   In this manner, one or more configurations of tools may be utilized on one or more of the elements of the vertebral stabilization assembly  10  and are within the spirit and scope of the present invention as disclosed and described herein. Furthermore, it will be appreciated that the opening  296  provided on the first connecting screw  40  or on the distal end  102  of the first pedicle screw  12  may be tapped and threaded opening in a standard or reverse threaded manner for engagement of, for example, the connector  290  having a threaded connector  290  (not shown) for engagement of the tool  280  to the first connecting screw  40  or the first pedicle screw  12 . 
   Also, for example, where the distal end  102  of the first pedicle screw  12  is substantially rectangularly shaped, such as in the aspect illustrated in FIG.,  11 , the connector  290  of the tool  280  may be configured to receive the rectangular distal end  102  of the first pedicle screw  12  or a rectangularly shaped second end  64  of the first connecting screw  40 . Many other configurations of the distal end  102  of the pedicle screw, such as the first pedicle screw  12 , and connecting screws, such as the first connecting screw  40 , may be provided and associated tools  280  having connectors  290  for connection thereto and will readily suggest themselves to one of ordinary skill in the art and are within the spirit and scope of the present invention described and disclosed herein. 
   Furthermore, it is within the spirit and scope of the present invention that the first connecting screw  40  may be provided with a double-bolted configuration on the threaded portion  66  of the first connecting screw  40  and the connector  290  may be a socket-type connection to receive the bolt or bolts for removal of the first connecting screw  40  utilizing the tool  280 . 
     FIG. 19  illustrates a bore screw  300  which may be utilized according to one aspect of the present invention. The bore screw  300  may be provided with threads (not shown) and may be placed obliquely from the posterior side  122  of the vertebra  118 . The bore screw  300  may be sized such that the diameter  302  of the bore screw  300  is sized substantially similar to or smaller than the diameter of the pedicle screw, such as the first pedicle screw  12 . However, it will be appreciated that in other aspects it may be advantageous for the diameter  302  of the bore screw  300  to be substantially similar in size to that of the first pedicle screw  12  or, in some instances, for the diameter  302  to be substantially larger. 
   The bore screw  300  is shown disposed in the pedicle  120  at a desirable angle extending through the vertebra  118 . In this manner the bore screw  300  may be utilized to create a bore opening (not shown) that may be useful for placing the pedicle screw, such as the first pedicle screw  12 , for placement of the pedicle screw from the anterior side  124  of the vertebra  118 . In such a procedure the bore screw  300  may be percutaneously placed in the posterior  122  of the vertebra  118 . Thereafter the patient may be rotated such that the anterior  124  of the vertebra  118  is exposed. The bore screw  300  may be provided with a coupling portion  308  adapted for attachment by a tool (not shown) for removal of the bore screw  300  through the anterior  124  side of the vertebra  118 . 
   In other aspects, the bore screw  300  may be utilized from the anterior  124  for tapping the vertebra  118 . In other aspects, the coupling portion  308  is adapted to engage the guide member  150  for determining alignment. For example, the guide member  150  may be attached to the coupling portion  308  of the bore screw  300  to determine the approximate location of the connecting screw, such as the first connecting screw  40 , and where the second end  64  of the first connecting screw  40  will be exposed on the anterior  124  side of vertebra  118 . 
   Attachment of the guide member  150  to the bore screw  300  provides another advantage of the present aspect in that it may be easily determined whether the bore screw  300  is placed at the appropriate location in the vertebra  118  or whether another placement will be necessary. This eliminates the need to place the pedicle screw, such as the first pedicle screw  12 , and then determine whether the placement is acceptable. 
     FIG. 20  illustrates a bore opening  310  which may have been created by the bore screw  300 , or in other embodiments may have been created by a drill or other device capable of creating an opening in the vertebra  118 . An indicator  312  is shown disposed in the bore opening  310 . The indicator is provided with a shaft  314  and a light  316  provided on one end of the shaft  314 . The light  316  may be a common LED (light emitting diode) or other light-emitting device which is suitable for these purposes, and may include laser light or laser light-emitting diodes. 
   The shaft  314  may be a substantially rigid shaft of sufficient length to extend down the length of the bore opening  310  and be operable to retain the light  316  and communicate sufficient electrical power to maintain the light  316  with power for driving the light  316 . In other aspects, the shaft  314  may be a substantially flexible material such as wire or other flexible cording or material. 
   The indicator  312  is a useful device for indicating the location of the bore opening  310  from the anterior side  124  of the vertebra  118 . As previously discussed, a number of soft tissues exist on the right side  126  on the anterior side  124  of the vertebra  118 . For this reason, whether a bore screw  300  or a drill is utilized to create the bore opening  310  from the posterior side  122 , it will be necessary in many cases to prevent penetration of the bore screw  300  or drill completely through the vertebra  118  on the anterior side  124  to prevent damage to the soft tissues on the anterior side  124 . The indicator  112  provides an opportunity once the patient has been rotated to retract the soft tissues and identify the location of the bore opening  310  from the anterior side  124 . 
   For example, the light  316  shown in the bore opening  310  will be perceptible by the surgeon from the anterior side  124  of the vertebra  118 . The surgeon may then drill from the anterior side  124  to complete the bore opening  310 . Where the bore screw  300  is utilized, the bore screw may be provided with a light, such as the light  316 , provided on the distal end of the bore screw  300  and will be sufficient for these purposes. Once the light  316 , whether provided on the indicator  312  or the bore screw  300 , has been identified and the bore opening has been drilled to communicate with the anterior side  124  of the vertebra  118 , the indicator  312  or bore screw  300  may then be removed from the anterior side. The indicator  314 , such as when the light  316  is a high intensity LED or laser light, may be disposed near the posterior side  122  or only slightly within the bore opening  310  such that the light produced by the light  316  projects down through the bore opening  310  and is sufficient to identify the bore opening  310  from the anterior side  124  of the vertebra  118 . 
   Furthermore, the indicator  312  may, in other aspects, be provided with a pneumatic or hydraulically operated capability for punching or extending through the anterior side  124  of the vertebra  118  when the indicator  312  is extended through the bore opening  310 , such as by utilizing a drill. In this manner, the indicator  312  may be left in place in the bore opening  310  and after the patient has been rotated such that the anterior side  124  of the vertebra  118  has been exposed, the pneumatic or hydraulically-operated indicator  312  may be activated so as to extend through the anterior side  124  for communication into the bore opening  310 . 
   The indicator  312  may be pulled through the anterior side  124  of the vertebra  118 , and in instances where the shaft  314  is a flexible material, it may be severed from, for example, behind the patient, for easy removal through the anterior side  124 . Where the bore screw  300  is utilized and still in place, a tool (not shown) may be connected to the coupling portion  308  of the bore screw  300  so that the bore screw  300  may be removed through the anterior side  124  of the vertebra  118 . This is advantageous since it eliminates the rotation of the patient for removal of the bore screw  300  or the indicator  312 . The elimination of a rotational procedure further reduces the time of the overall procedure and is another advantage of the present aspect of the vertebral stabilization assembly  10  invention disclosed herein. 
     FIG. 21  illustrates another aspect of the vertebral stabilization assembly  10  of the present invention. In this aspect the pedicle screw, such as the first pedicle screw  12 , is placed in the vertebra  118  from the anterior side  124 . By utilizing the bore opening  310 , the pedicle screw  12  may be more easily and accurately placed into the vertebra  118  from the anterior side  124 . Placement of the first pedicle screw  12  from the anterior side  124  has a number of advantages including that the angle of placement has been previously defined by the bore opening  310 . This allows for selection of the first pedicle screw  12  having an engaging portion  22  provided with the appropriate angle  320  with respect to connection of the connecting screw, such as the first connecting screw  40  (shown in phantom). 
   It will be appreciated that the exact angle of placement of the first pedicle screw  12  and resulting angle  320  with respect to the engaging portion  22  and first connecting screw  40  will be unknown until such time that the first pedicle screw  12  is actually in place in the vertebra  118 . By previously providing the bore opening  310 , the proper pedicle screw may be selected based upon the desired resulting angle  320  sought for the resulting placement of the first connecting screw  40 . That is, it may be advantageous in certain instances to provide the second end  64  of the first connecting screw  40  at a specific location on the left side  128  on the anterior side  124  of the vertebra  118 . Unless the first pedicle screw  12  is exactly placed, the resulting location of the second end  64  of the first connecting screw  40  may be significantly different than that desired. For this reason, a number of pedicle screws may be advantageously provided to the surgeon each having a different length and a different engaging portion  22  with respect to the angle of connection of the first connecting screw  40  to the engaging portion  22 . By having a number of choices available to the surgeon, and based upon the angle of the bore opening  310 , the first pedicle screw  12  may be selected as having an engaging portion  22  that will provide the angle  320  that will result in the second end  64  of the first connecting screw  40  being positioned at the desired location on the anterior side  124  of the vertebra  118 . 
   Anterior side  124  placement of the first pedicle screw  12  within the vertebra  118  provides numerous additional advantages including the dimensions of the first pedicle screw  12  and resulting stability that may be achieved from such placement. For example, the first pedicle screw  12 , such as that illustrated in  FIGS. 4 and 13 , may be readily utilized for these purposes, and may achieve advantageous stabilization by being placed from the anterior  124  side of the vertebra  118 . For example, with respect to the first pedicle screw  12  illustrated in  FIG. 13 , it can be seen that the diameter  232  of the reinforced portion  230  is slightly smaller than the diameter  246  of the plurality of threads  244  according to one aspect. 
   Since the reinforced portion  230  will not obtain the threading engagement, it is necessary for the plurality of threads  244  of the first pedicle screw  12  to be slightly larger to achieve a satisfactory anchoring and threading engagement of the first pedicle screw  12 . Otherwise, the reinforced portion  230  might have the affect of smoothing the opening such that the plurality of threads  244  do not successfully engage within the vertebra  118 . 
   Conversely, anterior side  124  placement of the pedicle screw allows for the plurality of threads  238  near the distal end  102  of the first pedicle screw  12  to be of a maximum diameter  240  for optimum anchoring and stabilization of the pedicle screw within the vertebra  118  and particularly within the pedicle portion  120 . At the same time, the diameter  232  of the reinforced portion  230  may be of a maximum diameter for reinforcement to optimize the connection and engagement of the first connecting screw  40  and such structure will not reduce or minimize the engagement of the first pedicle screw  12  with the vertebra  118 . The reason for this is that the plurality of threads  238  will be in front of the reinforced portion  230  when anteriorly placed versus behind the reinforced portion  230 , as is the case with the plurality of threads  244  when the pedicle screw  12  is posteriorly placed. In one aspect, diameter  232  of the reinforced portion  230  is similarly sized relative to the diameter  246  of the plurality of threads  244  or any other threads provided on the shaft  16 . However, numerous configurations of shaft  16  sized and thread sizes will readily suggest themselves to one of ordinary skill in the art and are within the spirit and scope of the present invention. 
   It should be appreciated that a variety of configurations of pedicle screws have been disclosed and shown herein and any of the various configurations may be utilized both for posterior placement of the first pedicle screw  12  as well as for anterior placement of the first pedicle screw  12 . Furthermore, it will be appreciated that a number of tools, such as the tool  280  illustrated in  FIGS. 17 and 18 , have been shown and described and may be readily implemented on the first pedicle screw  12  for anterior placement. 
     FIG. 22  illustrates the first pedicle screw  12  connecting to the guide member  150  for proper alignment of the connecting screw, such as the first connecting screw  40  to the first pedicle screw  12 . In one aspect, the present invention is directed to the vertebra stabilization assembly  10  wherein the complete procedure may be accomplished from the anterior side  124  of the vertebra  118 . The procedure for such placement may include drilling a hole utilizing a drill or other device or implement through the outer surface of the anterior side  124  of the vertebra  118  to penetrate the hard outer bone surface. 
   Thereafter utilizing technology typically employed for such purposes, such as an image intensifier, x-ray and templates, and/or other stealth technology, a K-wire or other drill or penetrating implement may be utilized to penetrate in a direction toward the posterior side  122  along a line  326 . The K-wire may be obliquely placed through the vertebral body into the pedicle  120  on the right side  126 . A cannulated drill may be utilized to drill over the K-wire to ream out a hole or opening for placement of the first pedicle screw  12  therein. The drill and K-wire may be removed and the first pedicle screw  12  may be anteriorly placed in the drilled opening substantially along the line  326  for proper placement of the first pedicle screw  12  in the vertebra  118 . This aspect, as previously discussed, advantageously provides for selecting, in advance, the proper pedicle screw, such as the first pedicle screw  12 , having the engaging portion  22  to achieve the desired angle of connection of the connecting screw, such as the first connecting screw  40 . 
   Another advantage of anterior placement of the first pedicle screw  12  is that it provides the opportunity for stabilization from the posterior side  122  when such may be desirable. In this aspect, the first pedicle screw  12 , such as that illustrated and previously disclosed herein in a number of different embodiments, may be utilized by placement initially from the anterior side  124  such that the distal end  102  is anchored substantially in the pedicle  120  portion of the vertebra  118 . Thereafter, the first pedicle screw  12  may be utilized for connection of connecting members, such as the connecting member  50 , for standard posterior anchoring and stabilization when such is necessary because of a failure to achieve adequate stabilization from the anterior side  124  as preferably provided herein. 
   Under the preferred anterior stabilization and when the first pedicle screw  12  is placed from the anterior side  124  of the vertebra  118 , the first pedicle screw  12  is provided with a coupling portion  100  near the head  60  of the first pedicle screw  12 , substantially as shown in  FIG. 22 . 
   Utilization of the vertebral stabilization assembly  10  according to the aspect illustrated in  FIG. 22 , has the additional advantage of completely eliminating rotation of the patient during the procedure. However, it will be appreciated that there may be certain instances when it is necessary or useful to rotate the patient for posterior access to the vertebra  118  and such rotation will not reduce or detract from the advantages of the vertebral stabilization assembly  10  of the present invention in that a significant portion or all of the procedure may be achieved from the anterior side  124  of the vertebra  118 . This presents a significant advantage in that rotation of the patient takes considerable time and eliminating the necessity for such rotation shortens the time period required for the procedure. 
   Once the first pedicle screw  12  has been placed on the anterior side  124  of the vertebra  118  substantially as shown and discussed above with respect to  FIG. 22 , the guide member  150  may be connected to the first pedicle screw  12  at the coupling portion  100  in a manner similar to that previously shown and described with respect to the coupling portion  100  and a guide member  150 . Utilization of the guide member  150  as well as the connection of the connecting screws, such as the first and second connecting screws  40  and  42 , as well as the bracket  50  remains substantially similar to that previously shown and described herein. 
   It should be appreciated that it is within the scope of the present invention to anteriorly place the first pedicle screw  12  on the left anterior side  124 , similar to that shown in  FIG. 8  except the first pedicle screw  12  is placed from the anterior instead of posterior of the vertebra  118 . In fact, in some instances, anterior placement on the left side may be advantageous. The reason that this placement may be preferable is that the angle of the shaft  16  of the first pedicle screw  12  is more shallow with respect to the first connecting screw  40 . This shallower angle will require a smaller guide member  150  and result in the surgery being performed in a smaller physical area. Since space is limited in the cavity of the patient, this configuration may be useful in some circumstances. Also, anterior placement of the pedicle screw on the left side may be utilized as a salvage when the right side becomes fractured or the desired stabilization is not obtained on the right side of the vertebra  118 . 
     FIG. 23  illustrates another aspect of the engaging portion  22  of the first pedicle screw  12  according to another aspect of the present invention. As previously discussed, depending upon the oblique angle of placement of the first pedicle screw  12  with respect to the vertebra  118 , the angle of engagement of the first connecting screw  40  with the first pedicle screw  12  may necessarily vary. For this reason, the present invention is further directed to an engaging opening  330  wherein the engaging portion  22  is retained within the shaft  16  of the first pedicle screw  12 . 
   In this manner, the engaging portion  22  may be retained in the manner such that the engaging portion  22  may be rotated to receive the first connecting screw  40  at various angles  332 . Although two angles  332  are shown, a variety of angles may be achieved utilizing the present aspect of the engaging portion  22 . The engaging portion  22  may be retained on bearings or other floating structural devices within the engaging opening  330 , such that when the first connecting screw  40  is coupled with the engaging portion  22 , the engaging portion  22  becomes fixed with respect to the initial angle  332  of engagement. 
   Such variable positioning of the engaging portion  22  can further be obtained by a hinge or a latch connected to the engaging portion  22  for hinging or latching rotation at the engaging portion  22  within the engaging opening  330 . Also, the engaging portion  22  may be provided on a rotational or ratcheted body (not shown) within the engaging opening  330 . It will be appreciated that a wide variety of structures may be utilized for obtaining and achieving an engaging portion, such as the engaging portion  22  to obtain various angulation, such as the angles  332  of connection of the first pedicle screw  12  relative to the first connecting screw  40  and are well known to those of ordinary skill in the art and are within the spirit and scope of the present invention and for brevity will not be further discussed herein. 
   The advantage of the engaging portion  22  adapted for angular adjustment is that it eliminates the need for a number of pedicle screws having different engaging portions with different angles for connection to the first connecting screw  40 . However, it should be appreciated that in other aspects the engaging portion  22  is a fixed and rigid structure for engagement of the first connecting screw  40  and, as such, a plurality of pedicle screws may be necessary each having a different angle of engagement of the first connecting screw  40  at the engaging portion  22  based upon the angle of placement of the first pedicle screw  12  in the vertebra  118 . 
   Furthermore, according to other aspects of the present invention, it is anticipated that a variety of pedicle screws, such as the first pedicle screw  12 , having significantly different lengths will be utilized for various adaptations and placements. Also, a variety of pedicle screws, such as the first pedicle screw  12 , where the fixed engaging portions  22  is available in variety of angles of connection of the connecting screw relative to the shaft  16  of the first pedicle screw  12 . 
     FIG. 24  illustrates another aspect of the present invention of the first pedicle screw  12 , wherein only a portion of the shaft  16  of the first pedicle screw  12  is illustrated. In this aspect the shaft  16  is provided with at least one non-continuous thread  336  extending circumferentially about the shaft  16  of the first pedicle screw  12 . In this manner, a first portion  338  of the non-continuous threads  336  extend circumferentially about a portion of the shaft  16  while a second portion of the non-continuous threads  336  extend about a second portion of the shaft  16 . 
   A gap  342  is disposed between the first portion  338  and the second portion  340  of the non-continuous threads  336 . The gap is a portion of the shaft  16  that is not provided with threads and may be of various circumferential dimensions and be suitable for these purposes. It will be appreciated that frequently the first pedicle screw  12  and particularly the threads on the shaft  16  may cause aggravation and irritation to nerves adjacent the vertebra  18 . Once it has been determined that a nerve is aggravated by the placement of the first pedicle screw  12 , adjustment or replacement of the first pedicle screw  12  is necessitated. Frequently, this requires completely removing and relocating the first pedicle screw  12  according to another oblique angle in the vertebra  118 . By providing the first pedicle screw  12  having one or more of the non-continuous threads  336 , according to the present aspect, aggravation of the nerve may be potentially alleviated by only a minor rotation of the first pedicle screw  12  since it is likely that the thread on the shaft  16  may be causing the irritation or aggravation of the nerve. Thus, upon a minor or slight rotation of the first pedicle screw  12  the gap  342  will replace, for example, the non-continuous threads  336  and alleviate the aggravation of the nerve and, thus, eliminate the necessity for completely removing and repositioning the first pedicle screw  12 . It will be appreciated, that the position and distribution of the non-continuous threads  336  with respect to their symmetrical placement may be altered or modified and are within the spirit and scope of the present invention as described and disclosed herein and will readily suggest themselves to one of ordinary skill in the art. 
     FIG. 25  illustrates another aspect of the vertebral stabilization assembly  10  having dual pedicle screws  400   a  and  400   b  for placement in the vertebra  118  to provide additional stability. The pedicle screws  400   a  and  400   b  are substantially similar to the first and second pedicle screws  12  and  14  in many aspects. The dual pedicle screws  400   a  and  400   b , however, are provided with engaging portions  402   a  and  402   b  relative to one another such that a connecting screw  404 , substantially similar to the first connecting screw  40 , may be connected to both the dual pedicle screws  400   a  and  400   b . The connecting screw  404  may be provided with a first end  406  adapted to be received by the engaging portion  402   a  of the pedicle screw  400   a . The connecting screw  404  is further provided with a shaft  408 , at least a portion of which is operative to connect to the engaging portion  402   b  of the pedicle screw  400   b . The dual pedicle screws  400   a  and  400   b  must be constructed and configured such that upon placement in the vertebra  118  pedicle screws  400   a  and  400   b  provide for such connection by the connecting screw  404 . 
   In some aspects the engaging portion  402   b  of the pedicle screw  400   b  may be an opening sufficient to receive the connecting screw  404  through the opening, as well as for engaging the shaft of  408  of the connecting screw  404 . It is readily apparent that this configuration of the dual pedicle screws  400   a  and  400   b  provides significant vertebral support and stability. Furthermore, although only the vertebra  118  is shown it should be understood that the present configuration, including the dual pedicle screws  400   a  and  400   b  and a connecting screw  404 , may be utilized for placement in a plurality of vertebra to provide increased stabilization for a plurality of vertebra for the purposes previously discussed and disclosed herein. 
   In another aspect, the present invention provides a fixation tool  430  for properly aligning the dual pedicle screws  400   a  and  400   b  for placement in the vertebra  118 . Accurate alignment and placement of the dual pedicle screws  400   a  and  400   b , according to one aspect, may be advantageously provided by utilizing the fixation tool  430 . The fixation tool  430  is provided with alignment members  432   a  and  432   b  to achieve the proper alignment of the dual pedicle screws  400   a  and  400   b  in the vertebra  118 . The alignment members  432   a  and  432   b  may be similar to the alignment member  156  of the guide member  150  previously disclosed and described above. 
   It may be advantageous, according to other aspects, to provide indicia on the dual pedicle screws  400   a  and  400   b  to provide for the proper alignment of the pedicle screws  400   a  and  400   b . In other aspects the fixation tool  430  may be unnecessary when employing x-ray, stealth, or other imaging technologies to ensure the accurate alignment and placement of the dual pedicle screws  400   a  and  400   b . In other aspects, however, the fixation tool  430  may be used such that the dual pedicle screws  400   a  and  400   b  may be simultaneously placed to ensure the engaging portions  402   a  and  402   b  of the dual pedicle screws  400   a  and  400   b , respectively, are in proper alignment for connection by the connecting screw  404 . 
   The pedicle screws  400   a  and  400   b  may also utilize guiding and locating techniques, previously discussed above, such that the pedicle screws  400   a  and  400   b  may be placed posteriorly, percutaneously or otherwise, and the connecting screw  404  may be placed anteriorly. Once the pedicle screws  400   a  and  400   b  have been inserted, the patient may then be rotated. A guide member, such as the guide member  150  may be utilized for connection and alignment of the connecting screw  404 , as previously discussed above. 
   Thus, the guide member  150  is coupled, for example, to the pedicle screw  400   a  such that the alignment member  156  is operable to properly align the connecting screw  404  for coupling to the dual pedicle screws  400   a  and  400   b . This may include, as previously discussed, drilling a tap hole or other guiding hole for accurate placement and alignment of the connecting screw  404 . In any event, the connecting screw  404  may then be connected to the dual pedicle screws  400   a  and  400   b  in a configuration substantially as illustrated in the present aspect. 
     FIG. 26  illustrates another aspect of the present invention utilizing dual pedicle screws  400   a  and  400   b  for anterior placement. It will be appreciated, as previously discussed, that one advantage of the present invention is placement of the pedicle screws from the anterior side  124  of the vertebra  118 . The current aspect illustrates another embodiment of the fixation tool  430  having alignment members  432   a  and  432   b  for alignment of the dual pedicle screws  400   a  and  400   b , respectively, from the anterior side  124  of the vertebra  118 . The fixation tool  430  may also combine the alignment features of the guide member  150  (See  FIG. 25 ) to achieve the proper alignment of the connecting screw  404  as well. 
   In one aspect, the fixation tool  430  may be implemented by determining the point  440  on the vertebra  118  to desirably place the connecting screw  404 . A pin, tack or other means may be employed to position and orient the alignment portion  442  which will provide the proper alignment for the connecting screw  404 . Once the desired placement for the connecting screw  404  has been located, the dual pedicle screws  400   a  and  400   b  may then be aligned and placed in the vertebra  118  utilizing the alignment members  432   a  and  432   b  of the alignment tool  430 . In some aspects the alignment members  432   a  and  432   b  may be provided with an inner and an outer barrel (not shown) wherein the inner barrel may be utilized to drill a guide hole in the vertebra  118  and the outer barrel may then be used to guide the pedicle screws  400   a  and  400   b  into place. 
     FIG. 27  illustrates another aspect of the present invention wherein the connecting screw  404  may be placed across the body of the vertebra  118 . In many instances it may be advantageous to position the connecting screw  404  in such a manner for coupling of the connecting screw  404  to adjacent vertebra similarly stabilized. It is within the spirit and scope of the present invention that such placement of the connecting screw  404  may still utilize the additional stability provided by one or more pedicle screws  400   a  and  400   b . The pedicle screw  400   b  is illustrated in phantom to denote that such placement of the connecting screw  404  may not necessitate placement of dual pedicle screws  400   a  and  400   b  and only one pedicle screw  400   a  may be sufficient to provide the desired stability in these instances. 
     FIG. 28  illustrates another aspect of the present invention utilizing a vertebral screw  412  for lateral placement in the body of the vertebra  118 , and a connecting screw  416  for anterior placement in the body of the vertebra  118 . It will be appreciated, as previously discussed, that one advantage of this aspect of the present invention is anterior placement of the connecting screw  416  in the body of the vertebra  118 . The current aspect also illustrates another embodiment of the fixation tool  430  having alignment members  432   a  and  432   b  for alignment of the vertebral screw  412  and the connecting screw  416 , respectively. 
   Similar to the pedicle screw  12 , the vertebral screw  412  is provided with an engaging portion  414 . Similar to the connecting screw  40 , the connecting screw  416  is provided with a first end  418  adapted to be received by the engaging portion  414  of the vertebral screw  412 . 
   In the current aspect, the fixation tool  430  may again be implemented by determining the point  440  on the vertebra  118  to desirably place the connecting screw  416 . A pin, tack or other means may be employed to position and orient the alignment member  432   b  of the alignment tool  430  so as to provide the proper alignment for the connecting screw  416 . Once the desired position for the connecting screw  416  has been located, the vertebral screw  412  may then be aligned and placed in the vertebra  118  utilizing the alignment member  432   a  of the alignment tool  430 . In some aspects the alignment members  432   a  and  432   b  may be provided with an inner and an outer barrel (not shown) wherein the inner barrel may be utilized to drill a guide hole in the vertebra  118  and the outer barrel may then be used to guide the connecting screw  416  and the vertebral screw  412  into place. 
   At this point it should be noted that although the vertebral screw  412  is shown extending across the entire body of the vertebra  118 , and even protruding from both sides of the vertebra  118 , the present invention is not limited in this regard. That is, it is within the scope of the present invention to have the vertebral screw  412  only protrude from one side of the vertebra  118 . 
     FIG. 29  illustrates another aspect of the vertebral stabilization assembly  10  utilizing the aspect set forth in  FIG. 28 . Similar to  FIG. 1 , the vertebral stabilization assembly  10  of  FIG. 29  comprises a first vertebral screw  12  and a second vertebral screw  14 . The first vertebral screw  12  includes a shaft  16  provided with a threaded portion  18 . The threaded portion  18  of the shaft  16  is operable for threading engagement of the first vertebral screw  12  with a first vertebra  20 . The shaft  16  of the first vertebral screw  12  further includes an engaging portion  22 . 
   The second vertebral screw  14  is substantially similar to the first vertebral screw  12  in that the second vertebral screw  14  includes a shaft  30  provided with a threaded portion  32 . The threaded portion  32  of the shaft  30  is operable for threading engagement of the second vertebral screw  14  with a second vertebra  34 . The shaft  30  of the second vertebral screw  14  is provided with an engaging portion  36 . 
   The shafts  16  and  30  of the first and second vertebral screws  12  and  14  are of appropriate length to sufficiently anchor the first and second vertebral screws  12  and  14  in the first and second vertebra  20  and  34 , respectively. The threaded portions  18  and  32  of the first and second vertebral screws  12  and  14  may be threads similar to those on ordinary screws and extending a distance from the shafts  16  and  30  sufficient to promote optimum anchoring of the first and second vertebral screws  12  and  14  within the first and second vertebra  20  and  34 , respectively. The first and second vertebral screws  12  and  14  are preferably constructed of a substantially rigid material such as, but not limited to, titanium, steel, metal, metal alloys, polymeric material, or a variety of other substantially rigid materials adapted to promote rigid engagement of the first and second vertebral screws  12  and  14  to the first and second vertebra  20  and  34 , respectively. 
   The vertebral stabilization assembly  10  is further provided with a first connecting screw- 40  and a second connecting screw  42 . The first and second connecting screws  40  and  42  may be constructed from substantially rigid materials similar to that of the first and second vertebral screws  12  and  14 , such as, but not limited to, titanium, steel, metal, metal alloys, polymeric material, or a variety of other substantially rigid materials adapted and suitable for these purposes. The first connecting screw  40  has a first end  44  adapted to be received by the engaging portion  22  on the shaft  16  of the first vertebral screw  12 . The second connecting screw  42  has a first end  46  adapted to be received by the engaging portion  36  of the shaft  30  of the second vertebral screw  14 . 
   The first and second vertebral screws  12  and  14  are each provided with a head  60  and  62 , respectively. The heads  60  and  62  of the first and second vertebral screws  12  and  14  may be configured to receive a tool, such as, but not limited to, is a standard flat or a Phillips-head screw driver, Allen or other wrench connection, or a variety of male to female or female to male temporary interconnections for threadingly engaging the first and second vertebral screws  12  and  14  into the first and second vertebra  20  and  34 . 
   In other embodiments (not shown) the heads  60  and  62  of the first and second vertebral screws  12  and  14  may be configured unlike the head of a standard screw and instead unitarily formed, for example, rectangularly from the shaft  16  and  30  for mating engagement with a unique tool adapted to receive the rectangularly-formed shaft. 
   It will be appreciated that a variety of constructions and configurations of the heads  60  and  62  of the first and second vertebral screws  12  and  14  will readily suggest themselves to one of ordinary skill in the art and may be provided in numerous configurations such that a tool may be attached temporarily to the heads  60  and  62  for imparting a rotation upon the first and second vertebral screws  12  and  14 . 
   As mentioned above, the engaging portion  22  of the shaft  16  of the first vertebral screw  12  receives the first end  44  of the first connecting screw  40 . The engaging portion  22  of the shaft  16  may be a threaded opening formed in the shaft  16  of the first vertebral screw  12  and adapted to receive a threaded first end  44  of the first connecting screw  40 . In this manner the first connecting screw  40  threadingly engages the engaging portion  22  to achieve a rigid locking connection between the first vertebral screw  12  and the first connecting screw  40 . 
   In other embodiments (not shown) the engaging portion  22  may be a tension connection opening in the shaft  16  for receiving and engaging in a tensioning fashion the first end  44  of the first connecting screw  40 . In yet other embodiments (not shown) the engaging portion  22  may be a locking assembly adapted to receive the first end  44  of the first connecting screw  40  and lock it into place upon insertion. The locking engagement of the engaging portion  22  may be accomplished in a variety of manners including a keyed design of the engaging portion  22  such that when the first end  44  of the first connecting screw  40  is inserted into the engaging portion  22  it is locked into place upon rotation of the first connecting screw  40 . 
   Yet in other embodiments (not shown), the engaging portion  22  may be a modification to the outer surface of the shaft  16  of the first vertebral screw  12  such that the first end  44  of the first connecting screw  40  may be adapted to receive the engaging portion  22  of the shaft  16  within an opening in the first end  44  of the first connecting screw  40 . In this manner the locking or tensioning mechanism may be retained by the first end  44  of the first connecting screw  40  for engaging the first connecting screw  40  with the first vertebral screw  12 . 
   A number of other connections including spring, ball, or other tensioning connections, as well as, threading, locking, and other mating connections for engaging the first end  44  of the first connecting screw  40  with the engaging portion  22  of the shaft  16  of the first vertebral screw  12  will readily suggest themselves to one of ordinary skill in the art and are within the spirit and scope of the present invention. It will be appreciated that the engaging portion  36  of the shaft  30  of the second vertebral screw  14  may be constructed substantially identical to the engaging portion  22  of the shaft  16  of the first vertebral screw  12 . For purposes of brevity no further discussion of the engaging portion  36  is deemed necessary to enable one of ordinary skill in the art on the variety of means for engaging the first and second connecting screws  40  and  42  with the first and second vertebral screws  12  and  14  in light of the discussion regarding the engaging portion  22  of the first vertebral screw  12 . 
   The vertebral stabilization assembly  10  further includes a first horizontal connecting member  80  and a second horizontal connecting member  82 . The first horizontal connecting member  80  is coupled to the head  60  of the first vertebral screw  12  and to a second end  64  of the first connecting screw  40 . The coupling of the first horizontal connecting member  80  to the head  60  of the first vertebral screw  12  and to the second end  64  of the first connecting screw  40  may be accomplished in any number of a variety of manners, such as, for example, those described above with respect to  FIG. 2 . Similarly, the second horizontal connecting member  82  is coupled to the head  62  of the second vertebral screw  14  and to a second end  68  of the second connecting screw  42 . The coupling of the second horizontal connecting member  82  to the head  62  of the second vertebral screw  14  and to the second end  68  of the second connecting screw  42  may be accomplished in any number of a variety of manners, such as, for example, those described above with respect to  FIG. 2 . 
   The vertebral stabilization assembly  10  further includes a vertical connecting member  50  that has a first end  52  and a second end  54 . The first end  52  of the vertical connecting member  50  is coupled to the first horizontal connecting member  80 . The second end  54  of the vertical connecting member  50  is coupled to the second horizontal connecting member  82 . This arrangement enables stabilization of the first vertebra  20  and the second vertebra  34  relative to each other. 
   The vertical connecting member  50  may be constructed from a variety of substantially rigid materials similar to that of the first and second vertebral screws  12  and  14  such as, but not limited to, titanium, steel, metal, metal alloys, polymeric material, or other substantially rigid materials suitable for stabilization of the first and second vertebra  20  and  34  by coupling to the first and second horizontal connecting members  80  and  82 . 
   It should be appreciated that the coupling of the vertical connecting member  50  to the first and second horizontal connecting members  80  and  82  may be accomplished in any number of a variety of manners, such as, for example, those described above with respect to  FIG. 2 . In addition, the vertical connecting member  50  may comprise multiple vertical connecting members  50  coupled to the first and second horizontal connecting members  80  and  82 . These multiple vertical connecting members  50  may be coupled to the first and second horizontal connecting members  80  and  82  in any number of a variety of manners, such as, for example, those described above with respect to  FIG. 2 . 
   Thus, it is apparent that there has been provided, in accordance with the present invention, a vertebral stabilization assembly and method that satisfies one or more of the advantages set forth above. Although the preferred embodiment has been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the scope of the present invention, even if all of the advantages identified above are not present. For example, the various embodiments shown in the drawings herein illustrate that the present invention may be implemented and embodied in a variety of different ways that still fall within the scope of the present invention. 
   Also, the techniques, designs, elements, and methods described and illustrated in the preferred embodiment as discrete or separate may be combined or integrated with other techniques, designs, elements, or methods without departing from the scope of the present invention. Other examples of changes, substitutions, and alterations are readily ascertainable by one skilled in the art and could be made without departing from the spirit and scope of the present invention.