Patent Publication Number: US-9849054-B2

Title: Patient positioning support structure

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/627,752, which was filed Oct. 17, 2011, and which is incorporated by reference herein. This application is a continuation-in-part of U.S. application Ser. No. 12/803,173, filed Jun. 21, 2010, which is a continuation-in-part of U.S. application Ser. No. 12/460,702, filed Jul. 23, 2009, now U.S. Pat. No. 8,060,960, which is a continuation of U.S. application Ser. No. 11/788,513 filed Apr. 20, 2007, now U.S. Pat. No. 7,565,708, which claimed the benefit of U.S. Provisional Application No. 60/798,288, filed May 5, 2006 and is a continuation-in-part of U.S. application Ser. No. 11/159,494 filed Jun. 23, 2005, now U.S. Pat. No. 7,343,635, which is a continuation-in-part of U.S. application Ser. No. 11/062,775, filed Feb. 22, 2005, now U.S. Pat. No. 7,152,261. 
    
    
     BACKGROUND OF THE INVENTION 
     The present disclosure is broadly concerned with structure for use in supporting and maintaining a patient in a desired position during examination and treatment, including medical procedures such as imaging, surgery and the like. More particularly, it is concerned with structure having patient supports that can be adjusted to allow a surgeon to selectively position the patient for convenient access to the surgical field and provide for manipulation of the patient during surgery including the tilting, angulation or bending of a trunk and/or a joint of a patient while in a generally supine, prone or lateral position. It is also concerned with structure for adjusting and/or maintaining the spatial relation between the inboard ends of the patient supports and for synchronized translation of the upper body of a patient as the inboard ends of the two patient supports are angled upwardly and downwardly. 
     Current surgical practice incorporates imaging techniques and technologies throughout the course of patient examination, diagnosis and treatment. For example, minimally invasive surgical techniques, such as percutaneous insertion of spinal implants involve small incisions that are guided by continuous or repeated intra-operative imaging. These images can be processed using computer software programs that product three dimensional images for reference by the surgeon during the course of the procedure. The patient support system should be constructed to permit unobstructed movement of the imaging equipment and other surgical equipment around, over and under the patient throughout the course of the surgical procedure without contamination of the sterile field. 
     It is also necessary that the patient support system be constructed to provide optimum access to the surgical field by the surgery team. Some procedures require positioning of portions of the patient&#39;s body in different ways at different times during the procedure. Some procedures, for example, spinal surgery, involve access through more than one surgical site or field. Since all of these fields may not be in the same plane or anatomical location, the patient support surfaces should be adjustable and capable of providing support in different planes for different parts of the patient&#39;s body as well as different positions or alignments for a given part of the body. Preferably, the support surface should be adjustable to provide support in separate planes and in different alignments for the head and upper trunk portion of the patient&#39;s body, the lower trunk and pelvic portion of the body as well as each of the limbs independently. 
     Certain types of surgery, such as orthopedic surgery, may require that the patient or a part of the patient be repositioned during the procedure while in some cases maintaining the sterile field. Where surgery is directed toward motion preservation procedures, such as by installation of artificial joints, dynamic stabilization systems, spinal ligaments and total disc prostheses, for example, the surgeon must be able to manipulate certain joints while supporting selected portions of the patient&#39;s body during surgery in order to facilitate the procedure. It is also desirable to be able to test the range of motion of the surgically repaired or stabilized joint and to observe the gliding movement of the reconstructed articulating prosthetic surfaces or the tension and flexibility of artificial ligaments, spacers and other types of dynamic stabilizers before the wound is closed. Such manipulation can be used, for example, to verify the correct positioning and function of an implanted prosthetic disc, spinal dynamic longitudinal connecting member, interspinous spacer or joint replacement during a surgical procedure. Where manipulation discloses binding, sub-optimal position or even crushing of the adjacent vertebrae, for example, as may occur with osteoporosis, the prosthesis can be removed and the adjacent vertebrae fused while the patient remains anesthetized. Injury which might otherwise have resulted from a “trial” use of the implant post-operatively will be avoided, along with the need for a second round of anesthesia and surgery to remove the implant or prosthesis and perform the revision, fusion or corrective surgery. 
     There is also a need for a patient support surface that can be articulated and angulated so that the patient can be moved when prone, for example, into an upwardly angled position or when supine into a downwardly angled position and whereby intra-operative bending (flexion and extension) of at least a portion of the spinal column can be achieved. The patient support surface must also be capable of easy, selective adjustment without necessitating removal and repositioning of the patient or causing substantial interruption of a surgical procedure. 
     For certain types of surgical procedures, for example spinal surgeries, it may be desirable to position the patient for sequential procedures done anteriorly, posteriorly and laterally. The patient support surface should be capable of providing correct positioning of the patient and optimum accessibility for the surgeon, as well as imaging equipment during such sequential procedures, when the patient is positioned prone, supine and lateral. 
     Articulated robotic arms are increasingly employed to perform surgical techniques. These units are generally designed to move short distances and to perform very precise work. Reliance on the patient support structure to perform any necessary gross movement of the patient can be beneficial, especially if the movements are synchronized or coordinated. Such units require a surgical support surface capable of smoothly performing the multi-directional movements which would otherwise be performed by trained medical personnel. There is thus a need in this application as well for integration between the robotics technology and the patient positioning technology. 
     While conventional operating tables generally include structure that permits tilting or rotation of a patient support surface about a longitudinal axis, previous surgical support devices have attempted to address the need for access by providing a cantilevered patient support surface on one end. However, existing cantilevered patient support structures are unsatisfactory, incorporating either a massive base to counterbalance the extended support member or a large overhead frame structure to provide support from above. The enlarged base members associated with such cantilever designs are problematic in that they can and do obstruct the movement of C-arm and O-arm mobile fluoroscopic imaging devices and other equipment. Surgical tables with overhead frame structures are bulky and may require the use of dedicated operating rooms, since in some cases they cannot be moved easily out of the way. Neither of these designs is easily portable or storable. 
     Articulated operating tables that employ cantilevered support surfaces capable of upward and downward angulation require structure to compensate for variations in the spatial relation of the inboard ends of the supports as they are raised and lowered to an angled position either above or below a horizontal plane. As the inboard ends of the supports are raised or lowered, they form a triangle, with the horizontal plane of the table forming the base of the triangle. Unless the base is commensurately shortened or the frame or patient support structure is elongated, a gap will develop between the inboard ends of the supports. 
     Such up and down angulation of the patient supports also causes a corresponding flexion or extension, respectively, of the lumbar spine of a supine or prone patient positioned on the supports. Raising the inboard ends of the patient supports generally causes flexion of the lumbar spine of a prone patient with decreased lordosis and a coupled or corresponding posterior rotation of the pelvis around the hips. When the top of the pelvis rotates in a posterior direction, it pulls the lumbar spine and wants to move or translate the thoracic spine in a caudad direction, toward the patient&#39;s feet. If the patient&#39;s trunk, entire upper body and head and neck are not free to translate or move along the support surface in a corresponding caudad direction in association with the posterior pelvic rotation, excessive traction along the entire spine can occur, but especially in the lumbar region. Conversely, lowering the inboard ends of the patient supports with downward angulation causes extension of the lumbar spine of a prone patient with increased lordosis and coupled anterior pelvic rotation around the hips. When the top of the pelvis rotates in an anterior direction, it pushes and wants to translate the thoracic spine in a cephalad direction, toward the patient&#39;s head. If the patient&#39;s trunk and upper body are not free to translate or move along the longitudinal axis of the support surface in a corresponding cephalad direction during lumbar extension with anterior pelvic rotation, unwanted compression of the spine can result, especially in the lumbar region. 
     Thus, there remains a need for a patient support system that provides easy access for personnel and equipment, that can be positioned and repositioned easily and quickly in multiple planes without the use of massive counterbalancing support structure, and that does not require use of a dedicated operating room. There is also a need for such a system that permits upward and downward angulation of the inboard ends of the supports, either alone or in combination with rotation or roll about the longitudinal axis, all while maintaining the ends in a preselected spatial relation, and at the same time providing for coordinated translation of the patient&#39;s upper body in a corresponding caudad or cephalad direction to thereby avoid excessive compression or traction on the spine. 
     SUMMARY OF THE INVENTION 
     The present disclosure is directed to a patient positioning support structure that permits adjustable positioning, repositioning and selectively lockable support of a patient&#39;s head and upper body, lower body and limbs in up to a plurality of individual planes while permitting rolling or tilting, angulation or bending and other manipulations as well as full and free access to the patient by medical personnel and equipment. The system of the invention includes at least one support end or column that is actively adjustable and is used to control the height, up and down angular orientation and side-to side tilting of the patient support structure. 
     The patient support structure includes first and second patient support frames connected together by a hinge assembly to form a patient support framework. One of the support frames is adapted to support the patient&#39;s lower body, the other to support the upper body, although it is to be understood that the support frames could be adapted to selectively support either the upper or lower body. The first patient support frame is supported on a pedestal or base that incorporates a lift mechanism for raising or lowering the first patient support frame, a translation mechanism, a mechanism to angulate the first patient support frame up or down and a side to side roll mechanism for rolling the first patient support frame. 
     In one embodiment, the second patient support frame is hingedly supported above the floor only through connections through the first patient support frame. One or more actuators connected between the first and second patient support frames control the angular orientation between the frames. 
     In another embodiment, the second patient support frame is supported proximate a distal end to a second end support column assembly. The second patient support frame is pivotally connected to the second end support column assembly to permit the second patient support section to passively pivot about a distal end pivot axis extending parallel to the hinge axis of the patient support. The first patient support frame is mounted to the pedestal on a carrier that is slidable relative to the pedestal in response to fore and aft pivoting of a pivotal support frame linkage or raising and lowering of the lift mechanism. 
     Various objects and advantages of this patient support structure will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this disclosure. 
     The drawings constitute a part of this specification, include exemplary embodiments, and illustrate various objects and features thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of a patient positioning structure having an adjustable pedestal base shown in a raised alignment and with a head end support column shown raised and a patient support structure connected between the pedestal base and the head end support column shown in a horizontal alignment. 
         FIG. 1A  is a perspective view of another embodiment of the patient positioning structure of  FIG. 1 . 
         FIG. 2  is a side, elevational view of the patient positioning structure as shown in  FIG. 1  with a controller and remote control unit shown schematically. 
         FIG. 3  is a top view of the patient positioning structure of  FIG. 1 . 
         FIG. 4  is an enlarged and exploded perspective view of a trunk translator shown disengaged from the patient positioning structure of  FIG. 1 . 
         FIG. 5  is an enlarged fragmentary perspective view of the base of a head end support column of the patient positioning structure of  FIG. 1 . 
         FIG. 6  is an enlarged and fragmentary, perspective view of the head end support column and a head end patient support of the patient positioning structure of  FIG. 1 . 
         FIG. 7  is an enlarged and fragmentary, side, elevational view of the patient positioning structure of FIG.  1 . 
         FIG. 8  is an enlarged and fragmentary, cross-sectional view of the patient positioning structure of  FIG. 1 , taken along line  8 - 8  of  FIG. 3 . 
         FIG. 9  is an enlarged and fragmentary, cross-sectional view of the patient positioning structure of  FIG. 1 , taken along line  9 - 9  of  FIG. 2 . 
         FIG. 10  is a side, elevational view of the patient positioning structure of  FIG. 1  showing foot end and head end patient supports pivoted in an upward breaking position and the pedestal and head end support column in lowered positions. 
         FIG. 11  is a side, elevational view of the patient positioning structure of  FIG. 1  showing the foot end and head end patient supports pivoted in a downward breaking position and with the pedestal and head end support column in raised positions. 
         FIG. 12  is a side elevational view of the structure of  FIG. 1  shown with a pair of planar patient support surfaces replacing the patient supports of  FIG. 1  and showing the pedestal raised and the head end support column lowered. 
         FIG. 13  is a side elevational view of an alternative embodiment showing a cantilevered patient positioning structure with a pedestal base supporting a foot end patient support and a head end patient support connected to and supported as a cantilever through the foot end patient support. 
         FIG. 14  is a top plan view of the cantilevered patient positioning structure as shown in  FIG. 13 . 
         FIG. 15  is a side elevational view of the cantilevered patient positioning structure of  FIG. 13  showing the foot end and head end patient supports pivoted in an upwardly breaking orientation. 
         FIG. 16  is a side elevational view of the cantilevered patient positioning structure of  FIG. 13  showing the foot end and head end patient supports pivoted in a downwardly breaking orientation and a trunk translator moving toward a head end of the head end patient support. 
     
    
    
     DETAILED DESCRIPTION 
     As required, detailed embodiments of the patient positioning support structure are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the apparatus, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the disclosure in virtually any appropriately detailed structure. 
     Referring now to the drawings, an embodiment of a patient positioning and support assembly, table or system according to the disclosure is generally designated by the reference numeral  1  and is depicted in  FIGS. 1-12 . The assembly  1  includes first and second patient support sections, frames or structures  3  and  4  connected together by spaced apart opposed hinges  6  and  7  to form an articulated patient support or patient support framework  8 . The first patient support frame  3  may be referred to as the lower body or foot end support frame  3  and the second patient support frame  4  may be referred to as the upper body or head end support frame  4 . Hinges  6  and  7  are formed or secured on hinge ends of the patient support frames  3  and  4 , such that the patient support frames  3  and  4  are connected together along a hinge axis, which is denoted by the letter A, that is substantially perpendicular to a longitudinal axis of the patient positioning and support assembly  1  and also substantially parallel with the floor. The hinges  6  and  7  enable rotation or angulation about the associated hinge axis A of the frames  3  and  4  relative to one another. 
     In the embodiment shown in  FIGS. 1-12 , the lower body support frame  3  is supported on a carrier  11 , or longitudinal translation subassembly, which is connected to and supported by an adjustable pedestal  12 . The pedestal  12  includes a foot end base  13 , a lift assembly or mechanism  15  operable to raise and lower the carrier  11  relative to the base  13  and a pedestal pivot assembly  16  operable to pivot the carrier  11  fore and aft and side to side relative to the base  13 . As used herein the base  13  generally comprises the lower portion of the pedestal  12  or associated structure that is adapted to contact or be positioned in close contact with the floor for supporting the patient support assembly  1 . 
     The carrier  11  and the attached lower body support frame  3  slide or translate relative to the pedestal  12  as the pedestal pivot assembly  16  pivots the carrier  11  fore and aft relative to the base  13 . The carrier  11  slides parallel to a longitudinal axis of the lower body support frame  3 . 
     The upper body support frame  4  is pivotally and rotatably supported at its distal end or head end  19  on a second end support column  21  supported on a second end base  23 . The second end support column  21  telescopes or vertically translates to adjust the height of the head end of the upper body support frame  4 . The foot end base  13  and second end base  23  are interconnected by a beam  25  or the like so that the spacing between the pedestal  12  and the second end support column  21  is fixed. The upper body support frame  4  freely pivots and rotates relative to the second end support column  21  to allow the upper body support frame  4  to pivot and rotate in response to raising or lowering, fore and aft pivoting or side to side rotation of the lower body support frame  3  in response to adjustments to the pedestal  12 . Operation of the pedestal  12  and other adjustments to the patient support assembly  1  may be controlled by a computer controller  26  shown schematically in  FIG. 2 . 
     The lower body support frame  3 , connected to pedestal  12 , is adapted to support the lower portion of a patient including the legs and up to the waist. The upper body support frame  4  is adapted to support the torso, arms and head of a patent. As best seen in  FIG. 3 , each patient support frame  3  and  4  is a generally U-shaped open framework with a pair of elongate, generally parallel spaced apart arms or support spars. The lower body support frame  3  includes spars  28   a  and  28   b  connected across a foot end by foot end cross bar  29 . The upper body support frame  4  includes spars  31   a  and  31   b  connected across a head end by head end cross bar  32 . The spars  28   a ,  28   b  and  31   a ,  31   b  are spaced so as to allow a prone patient&#39;s belly to depend therebetween. The lower body support frame  3  is illustrated with longer spars  28   a  and  28   b  than the spars  31   a  and  31   b  of the upper body support frame  4  to accommodate the longer, lower body of a patient. It is foreseen that all of the spars, and the patient support frames  3  and  4  may also be of equal length, or that the spars of upper body support frame  4  could be longer than the spars of the lower body support frame  3 , so that the overall length of frame  4  will be greater than that of frame  3 . It is also foreseen that a patient could be supported on the support framework  8  with his head supported on the first support frame  3  over the pedestal  12  and with his legs supported on the second support frame  4 . An optional cross brace (not shown) may be provided between the longer spars  28   a  and  28   b  of the lower body support frame  3  to provide additional stability and support. However, any cross brace is located so as to not substantially hinder dependence of the patient&#39;s belly between the spars  28   a ,  28   b  and  31   a ,  31   b , or between the hinges  6  and  7 . Hinges  6  and  7  connecting the first and second patient support frames  3  and  4  are connected between inner ends of spars  28   a  and  31   a  and spars  28   b  and  31   b . It is foreseen that the spars  28   a ,  28   b  of the lower body support frame  3  may be shaped so as to allow a patient&#39;s legs to depend therebetween. For example, as shown in  FIG. 1A , the spars  28   a ,  28   b  may be space farther apart, outwardly bowed, or otherwise shaped or contoured so as to allow a patient&#39;s legs to depend therebetween. For example, the spars may be spaced wider or offset with side-to-side hinges  6 ,  7 , to provide more room for the legs, such as but not limited to when a patient&#39;s legs are supported by a sling  28   c  suspended from the spars  28   a ,  28   b.    
     As best seen in  FIGS. 1-3 , the lower body support frame  3  is equipped with a pair of hip or lumbar support pads  38   a  and  38   b  that are selectively positionable for supporting the hips of a patient and are held in place by a pair of clamp style brackets or hip pad mounts  39   a ,  39   b  that surmount the respective spars  28   a  and  28   b . The hip pads  38   a  and  38   b  may be shaped or contoured, such as but not limited to as is shown in  FIGS. 3, 10-11 and 13-14 , so as to allow the patient&#39;s belly to depend therebetween without excessively pinching or compressing the patient&#39;s body. Each of the hip pad mounts  39   a  and  39   b  is connected to a hip pad plate  40   a  and  40   b  (not shown) respectively that extend at a downward angle. The hip pads  38   a  and  38   b  are thus supported at an angle that is pitched or directed toward the longitudinal center axis of the supported patient. It is foreseen that the plates  40   a  and  40   b  could be pivotally adjustable rather than fixed. The hip pad mounts  39   a  and  39   b  and the attached support pads  38   a  and  38   b  are removably connected to the spars  28   a  and  28   b  respectively. It is foreseen that a single hip pad may be used instead of the pair of hip pads  38   a  and  38   b.    
     The chest, shoulders, arms and head of the patient are supported by a trunk or torso translator assembly  43  that enables sliding translational movement of the head and upper body of the supported patient along a length of the upper body support frame  4  in both caudad and cephalad directions. The translational movement of the trunk translator  43  is coordinated or synchronized with the upward and downward angulation of the inboard or hinge ends of the upper and lower body patient supports  3  and  4 . 
     The translator assembly  43  is constructed as a removable component or module, and is shown in  FIG. 4  disengaged and removed from the structure  1 . The translator assembly  43  includes a head support portion or trolley  45  that extends between and is supported by a pair of elongate support or trolley guides  46   a  and  46   b . Each of the guides is sized and shaped to receive a portion of one of the spars  31   a  and  31   b  respectively of the upper body support frame  4 . The guides  46   a  and  46   b  are preferably lubricated on their inner surfaces to facilitate shifting or sliding back and forth along the spars  31   a  and  31   b . The guides  46   a  and  46   b  are interconnected at their inboard ends by a crossbar, cross brace or rail (not shown), which supports a sternum pad  49 . 
     An arm rest support bracket  51  is connected to each of the trolley guides  46   a  and  46   b  respectively. The support brackets  51  are generally Y-shaped with a lower leg  52  and an inner and outer branched arm  53  and  54  respectively. The inner branched arm  53  of each support bracket  51  is connected to the associated trolley guide  46   a  and  46   b . Each of the brackets  51  supports a respective arm rest  56 . It is foreseen that arm-supporting cradles or slings may be substituted for the arm rests  56 . Each lower leg  52  terminates in an expanded base  58 , so that the two brackets  51  form a stand for supporting the trunk translator assembly  43  when it is removed from the patient support assembly  1 . 
     The trunk translator assembly  43  includes a pair of linear actuators  60   a  and  60   b . Each actuator includes a motor  61 , a tubular housing  62  and an extendable shaft  63 . A distal end of the shaft  63  of each actuator  60   a  and  60   b  is pivotally connected to a flange  65  depending from a respective trolley guide  46   a  and  46   b . An opposite end of each linear actuator  60   a  and  60   b  is connected to a clevis  67  (see  FIG. 2 ) projecting from respective spars  31   a  and  31   b . The linear actuators  60   a  and  60   b  are controlled by computer controller  26  to adjust the position of the trunk translator  43  as the first and second support frames  3  and  4  pivot at the hinges  6  and  7  relative to one another. The actuators  60   a  and  60   b  preferably include integral position sensors which determine the degree of extension of the shaft  63  of each actuator and communicate this information to the controller  26 . Because the linear actuators  60   a  and  60   b  are connected to the trunk translator assembly  43 , the computer controller  26  can use the data to determine and coordinate the position of the trunk translator assembly  43  with respect to the spars  31   a  and  31   b . Accordingly, the position or location of the trunk translator assembly  434  is synchronized with the position or angulation of the hinges  6  and  7  by the computer controller  26 . Each of the linear actuators may incorporate an integral home switch, not shown. Cabling or the like for the actuators  60   a  and  60   b  is preferably routed within the patient support framework  8 . 
     It is foreseen that the position of the trunk translator  43  may be adjusted by a drive linkage (not shown) incorporated into the patient support framework  8 . Such a linkage would preferably extend through one or both of the spars  28   a  and  28   b  of the foot end patient support frame  3  and through one or both of the spars  31   a  and  31   b  of the head end patient support frame  4 . 
     The base  23  of the second end or head end support column  21  may include spaced apart casters or wheels  69  each equipped with a floor-lock foot lever for lowering the base  23  into a floor-engaging position. The column  21  includes two or more telescoping lift segments, such as lower lift segment  71 , medial lift segment  72  and upper lift segment  73  that permit the height of column  21  to be selectively increased and decreased in order to raise and lower the head end of the second patient support section  4 . Telescoping movement of the lift segments  71 - 73  may be controlled by hydraulic actuators, screws or other lifting mechanisms (not shown) the operation of which are controlled by controller  26 . 
     As best seen in  FIGS. 6 and 7 , the upper body patient support frame  4  is connected to the head end column  21  by a pivotal support frame linkage  74  which is connected to a head  76  of the upper lift segment  73 . The support frame linkage  74  includes a rotation subassembly  78  and an angulation subassembly  80  that are interconnected as will be described in greater detail below. The rotation subassembly  78  enables side to side pivoting, tilting, rolling or rotation of the head end patient support frame  4  about a longitudinal axis of rotation R (see  FIGS. 6-7 ) of the structure  1  in response to side to side pivoting of the carrier  11  by the pedestal pivot assembly  16 . The angulation subassembly  80  enables pivoting, tilting or rotation of the head end patient support frame  4  about an axis B (see  FIG. 6 ) extending laterally across the support frame linkage  74  which permits hinging or articulation of the patient support framework  8  at the hinges  6  and  7  at desired levels and increments as well as selective tilting of the patient support sections  3  and  4  with respect to a longitudinal axis of the support sections  3  and  4 . 
     The rotation subassembly or mechanism  78 , includes a longitudinal pivot shaft  82  pivotally mounted within and projecting from the upper lift segment head  76  and connected to a pivotal beam or strut  84 . The pivot shaft  82  is substantially coaxial with the longitudinal axis of rotation R. A pair of flanges  86 , each with a pin receiving aperture (not shown) formed therein, project outward from the beam  84  on opposite ends thereof and toward the foot end of the assembly  1 . The beam  84  and flanges  86  generally form a clevis for connecting the angulation subassembly  80  thereto. 
     The angulation subassembly  80  generally includes a vertical angulating connector  90 , a side to side pivot connector  92  and first and second pivot pins  94  and  95  associated therewith. Angulating connector  90  is positioned between and pivotally connected to the flanges  86  on beam  84  by first pivot pin  94  extending through pin receiving apertures in flanges  86  and through a first pivot bore  96 , which in some embodiments is an elongate slot, extending laterally through the connector  90  such that the connector  90  pivots between the flanges  86 . It is foreseen that in certain embodiments the bore  96  will not be required to be slot-shaped, to provide lateral translation compensation, because most or all of the longitudinal translation compensation may be actively provided in the foot end structures, such as but not limited to carriers  11  and similar translation structures. 
     The side to side pivot connector  92  connects the angulating connector  90  to the head end cross bar  32  of the head end patient support frame  4 . The pivot connector  92  includes first and second outwardly opening and opposed slots  102  and  103  formed therein. The first slot  102  is sized and shaped for receiving the angulating connector  90  and the second slot  103  is sized and shaped for receiving the head end cross bar  32 . The pivot connector  92  further includes a through bore  105  running substantially perpendicular to the first slot  102  and communicating therewith. The bore  105  is aligned with a second pivot bore  107  extending generally vertically through the angulating connector  90  with the second pivot pin  95  extending therethrough to permit the pivot connector  92  to pivot side to side relative to the angulating connector  90  providing a degree of freedom and clearance needed for rotation the patient support about a longitudinal axis of a patient. The head end cross bar  32  is fixedly secured within second slot  103 . 
     It is noted that the first pivot pin  94  is substantially coaxial with the axis B, which may be referred to as a pitch axis B. The second pivot pin  95  is substantially coaxial with a yaw rotational axis denoted by the letter C (see  FIGS. 6-7 ), which enables at least some rotational movement of the side pivot connector  92  with respect to the vertical angulating connector  90 . 
     Although the rotation subassembly  78  and the angulation subassembly  80  are generally shown as passive and allowing movement in response to active movement of the patient support framework  8  by the pedestal  12 , it is foreseen that drive means, such as a motor connected to shaft  82  could be used to actively rotate the shaft  82  and the head end patient support frame  4  and further actuating means could be used to pivot the head end patient support frame  4  relative to the rotation subassembly  78 . It is foreseen that the rotation subassembly  78  and the angulation subassembly  80  may be any other structure that enables rotational movement with respect to the axes R, B and C, such as but not limited to universal joints, ball joints and the like. 
     Referring to  FIGS. 8-10 , the lift assembly  15  of the pedestal  12  is shown as a jack  111  supported on the foot end base  13  and supporting a lift plate  113  connected to the jack  111 . Jack  111  as shown may be hydraulically or mechanically actuated and operation of the jack  111  is controlled by controller  26 . Extension of the jack  111  raises the lift plate  113  and retraction of the jack  111  lowers the lift plate  113 . A flexible or expandable enclosure  114  preferably surrounds the lift assembly  15  and is connected at one end to the lift plate  113  and at the other end to the base  13 . The enclosure  114  telescopes or expands and contracts as the lift plate  113  is raised and lowered. 
     The pedestal pivot assembly  16  includes a ball joint  115  connecting a swivel plate or panel  117  to the lift plate  113 . The ball joint  115  as shown includes a socket  119  mounted on top of the lift plate  113  and a ball member  121  connected to and depending from the swivel plate  117  and received in socket  119 . One or more linear actuators  123  (one shown) are operable to tilt or pivot the swivel plate  117  in a fore and aft direction relative to foot end base  13 . One or more linear actuators  125  (one shown) are operable to pivot or roll the swivel plate  117  side to side relative to the foot end base  13 . The linear actuators  123  and  125  may be hydraulic or mechanical actuators or the like and operation of the actuators  123  and  125  is controlled by controller  26 . Safety panels or shielding  126  depends from the swivel plate  117  along the sides and across the outer end of the pivot assembly  16 . 
     The carrier  11  is slidably mounted on the swivel plate  117  and slides longitudinally relative thereto. In the embodiment shown, the swivel plate  117  includes grooves  128  formed along the sides of the swivel plate  117  which receive opposed flanges  130  which project inwardly from legs  131  extending downwardly from the carrier  11 . A linear actuator  133  connected between the swivel plate  117  and the carrier  11  is operable by the controller  26  to slide the carrier  11  longitudinally relative to the swivel plate  117 . The carrier  11  may be described as supporting the lower body patient support frame  3  in cantilevered relationship. The pedestal  12  and base  13  extend below the carrier  11  and a distal portion of lower body support frame  3  to support the support frame  3  in a cantilevered arrangement. In the embodiment shown, the spars  28   a  and  28   b  of the lower body support frame  3  extend above the carrier  11  and pedestal  12  to provide unobstructed access to the patient supported thereon with equipment that can move over the foot end of the table  1 . 
     A user controls the positioning of the patient support framework  8  with a hand held controller  140  which communicates with the computer control system  26  which in turn controls the operation of the actuators and motors incorporated into the patient support structure  1 . Extending linear actuator  123 , tilts the swivel plate  117 , the attached carrier  11  and the lower body support frame  3  extending toward hinges  6  and  7  upward which results in the patient support framework  8  breaking upward as shown in  FIG. 10 . Retracting linear actuator  123  tilts the swivel plate  117 , attached carrier  11  and the lower body support frame  3  extending toward the hinges  6  and  7  downward which results in the patient support framework  8  breaking downward as shown in  FIG. 11 . As the hinge end of the lower body support frame  3  is raised or lowered, the adjacent hinge end of the upper body support frame  4  is raised or lowered due to its connection to the lower body support frame  3 . The upper body support frame  4  pivots about pivot pin  94  in the angulation subassembly  80  as the hinge end thereof rises and lowers. 
     As the lower body support frame  3  and upper body support frame  4  pivot from horizontal, the distance between the distal or outer ends of the support frames  3  and  4  decreases while the distance between the foot end base  13  and head end base  23  remains fixed. Sliding of the carrier  11  relative to the swivel plate  117  accommodates the reduction in distance between the ends of the support frames  3  and  4 . As the lower and upper body support frames  3  and  4  pivot upward, the carrier plate  11  generally slides toward the head end of the patient support assembly  1 . As the lower and upper body support frames  3  and  4  pivot downward, because the pivot point is below the carrier, the carrier  11  generally slides away from the head end of the patient support assembly  1 . 
     The controller  26  preferably controls the operation of actuators  60  for adjusting the position of the trunk translator  43  in response to changes in the breaking angle between the lower and upper body support frames  3  and  4 . Sensors, not shown, may be incorporated into the lower and upper body support frames  3  and  4  proximate hinges  6  and  7  to determine the breaking angle and use the sensed angle to operate actuators  60  to adjust the position of the trunk translator  43 . It is also foreseen that an operator can separately control the operation of actuators  60  and the position of the trunk translator  43  using the hand held controller  140 . It is also foreseen that the actuators  60  could be replaced by other types of drive linkages to control operation of the trunk translator  43 , including a drive linkage extending through the spars  28   a  and  28   b  and  31   a  and  31   b  of the support frames  3  and  4 . 
     The trunk translation assembly  43  enables coordinated shifting of the patient&#39;s upper body along the longitudinal axis of the patient support  11  as required for maintenance of normal spinal biomechanics and avoidance of excessive traction or compression of the spine as the breaking angle between the lower and upper body support frames  3  and  4  is adjusted. 
     Positioning of the translator assembly  43  may be based on positional data collection by the computer in response to inputs by an operator. The assembly  43  is initially positioned or calibrated within the computer by a coordinated learning process and conventional trigonometric calculations. In this manner, the trunk translator assembly  43  is controlled to travel or move a distance corresponding to the change in overall length of the base of a triangle formed when the inboard ends of the patient support frames  3  and  4  are angled upwardly or downwardly. The base of the triangle equals the distance between the outboard ends of the patient support frames  3  and  4 . The distance of travel of the trunk translator assembly  43  may be calibrated to be identical to the change in distance between the outboard ends of the patient support frames  3  and  4 , or it may be approximately the same. The positions of the patient support frames  3  and  4  are measured as they are raised and lowered, the assembly  43  is positioned accordingly and the position of the assembly is measured. The data points thus empirically obtained are then programmed into the computer controller  26 . 
     The actuator or actuators  60  drive the trolley guides  46  supporting the trolley  45 , sternum pad  49  and arm rests  56  back and forth along the spars  31   a  and  31   b  in coordinated movement with the spars  28   a  and  28   b . By coordinated operation of the actuators  60  with the angular orientation of the lower and upper body patient support frames  3  and  4 , the trolley  45  and associated structures are moved or translated in a caudad direction, traveling along the spars  31   a  and  31   b  toward the inboard articulation thereof, in the direction of the patient&#39;s feet when the ends of the spars are raised to an upwardly breaking angle as seen in  FIG. 10 , thereby avoiding excessive traction on the patient&#39;s spine. Conversely, by reverse operation of the actuators  60 , the trolley  45  and associated structures are moved or translated in a cephalad direction, traveling along the spars  31   a  and  31   b  away from the inboard articulation of the patient support frames  3  and  4 , in the direction of the patient&#39;s head when the ends of the spars are lowered to a downwardly breaking angle as seen in  FIG. 11 , thereby avoiding excessive compression of the patient&#39;s spine. It is foreseen that the operation of the actuators may also be coordinated with the tilt orientation of the patient support frames  3  and  4 . When not in use, the translator assembly  43  preferably is easily removed from the spars  31   a  and  31   b.    
     Operating linear actuators  125  to roll or pivot the swivel plate  117  side to side causes the carrier plate  11  and the lower body support frame  3  to pivot or roll side to side and the rotation subassembly  78  simultaneously allows side-to-side pivoting or rolling of the upper body support frame  4  about pivot shaft  82 . It is to be understood that the head end cross bar  32  can pivot about pivot pin  95  through pivot connector  92  to prevent binding when the patient support frames  3  and  4  roll side to side, particularly when the support frames  3  and  4  are in upwardly or downwardly breaking angular orientation relative to one another. 
     The height of the foot end of lower body support frame  3  is adjusted by extending or retracting jack  111 , the operation of which can be controlled through hand held controller  140 . Similarly, the height of the head end of upper body support frame  4  is adjusted by extending the middle and upper lift segments  72  and  73  relative to lower lift segment  71  of the head end support column  21  which may be controlled by hand held controller  140  interfacing with computer controller  26 . One or more linear actuators, not shown, mounted within the head end support column  21  may be used for raising and lowering the lift segments  72  and  73  relative to lift segment  71 . The upper body support frame  4  similarly pivots about pivot pin  94  in angulation subassembly  80  as the height of the head  76  of upper lift segment  73  rises and lowers. 
     The patient support frames  3  and  4  may be positioned in a horizontal or other convenient orientation and height to facilitate transfer of a patient onto the translator assembly  43  and hip supports  38 . The patient may be positioned, for example, in a generally prone position with the head supported on the trolley  45 , and the torso and arms supported on the sternum pad  49  and arm supports  56  respectively. A head support pad may also be provided atop the trolley  45  if desired. Once the patient is positioned on the translator assembly  43  and hip supports  38  or otherwise positioned on the support frames  3  and  4 , the controller  26  is then used to control the operation of the patient support structure  1  to position the patient in the desired alignment for the surgical procedure to be performed. As discussed previously, jack  111  is used to adjust the height of the foot end of the patient support framework  8  while head end support column  21  is adjusted to control the height of the head end of the framework  8 . Fore and aft pivoting of swivel plate  117  adjusts the breaking angle between the patient support frames  3  and  4  and side to side pivoting of the swivel plate  117  causes rolling of the support frames  3  and  4 . 
       FIG. 12  shows the support table  1  with the trunk translator assembly  43  and the hip supports  38  removed from the patient support framework  8  and replaced with lower and upper body support panels  151  and  152  for supporting a patient thereon. The lower body support panel  151  is connected to lower body support frame  3  and upper body support panel  152  is connected to upper body support frame  4  by bolting, clips or other fastening means. The patient is then supported on the panels  151  and  152 , in a prone, supine or lateral position. The panels  151  and  152  move with the support frames  3  and  4  to which they are attached. 
     An alternative embodiment of a patient support assembly  201  is shown in  FIGS. 13-16  and includes lower body and upper body support frames  203  and  204  which are connected together by hinges  206  and  207 . Patient support assembly  201  is constructed similar to assembly  1 , except that the head end of upper body support frame  204  is unsupported such that the patient support framework  208  is supported in a cantilevered fashion on the carrier  211  and pedestal  212 . The base  213  of the pedestal  212  is preferably enlarged relative to base  13  of assembly  1  to prevent tipping of the cantilevered support assembly  201 . 
     By supporting the patient support framework  208  above and only through the foot end pedestal  212 , diagnostic or imaging equipment may be more readily positioned relative to the patient supported on the framework  208  to procure images during a surgical procedure. As seen in the drawings, the upper body support frame  204  is only supported above the ground through its connection to and through the lower body support frame  203 . 
     Articulation of the upper body support frame  204  relative to the lower body support frame  203  in assembly  201  is controlled by actuators, such as linear actuators  214  connected between spars  228   a  and  231   a  and spars  228   b  and  231   b  of the patient support frames  203  and  204 . Operation of the actuators  214  to control the breaking angle between patient support frames  203  and  204  is controlled by computer controller  226 . Because the upper body support frame  204  is only supported through the lower body support frame  203 , the lower body support frame  203  is not required to slide relative to the pedestal  212 . In this embodiment, a carrier separate from the swivel plate  217  is not required and the swivel plate  217  may be described as or considered the carrier for the lower body support frame or section  203 . 
     The lower body and upper body support sections  203  and  204  are shown in an upwardly breaking orientation in  FIG. 15  and in a downward breaking position in  FIG. 16 , with the pedestal retracted in  FIG. 15  and extended in  FIG. 16 . A trunk translator assembly  243  similar in construction and operation as trunk translator  43  is mounted on the spars  231   a  and  231   b  of the upper body support frame  204 . 
     It is foreseen that in some embodiments that the actuator that moves the trunk translator relative to the housing may not be directly secured or affixed to the translator. In particular, an additional trolley may be utilized that rides on the frame or housing and that is secured to the actuator. The trunk translator portion that supports the patient is then separate from the trolley and removably sits on top of the trolley. The trolley may include vertical projections or the like to hold the translator so as to move with the trolley when placed thereon. It is also foreseen that the actuator may be enclosed within the frame or housing for a reduced profile. 
     In an exemplary embodiment, an apparatus  1  for supporting a patient above a floor during a medical procedure is provided, including an elongate patient support structure having a first section  3  hingedly connected to a second section  4  by a pair of spaced apart opposed hinges  6  and  7 , a base and a chest slide  43 . The base includes spaced opposed upright first and second end supports  12  and  21 , respectively. The first end support  12  is connected to an outer end of the first section  3  by a cantilever lifting mechanism  15  configured to move the hinges  6  and  7  upwardly and downwardly when the second end support  21  is connected to an outer end of the second section  4 , wherein at least one of the end connections therebetween is configured to provide for three degrees of rotational freedom including pitch, roll and yaw. For example, pitch may be provided by rotational movement about one or both of the hinge axes A and B, roll may be provided by rotational movement with respect to the longitudinally extending roll axis R, and yaw may be provided by rotational movement about the axis C associated with the pivot pin  95 . The a chest slide  43  is operational along at least one portion of at least one section of the patient support structure and in slidable relation therewith, wherein the chest slide  43  is mechanically non-linked to either of the hinges  6  and  7 . For example, the chest slide  43  may slidingly translate longitudinally along a length of the second section  4 . In a further embodiment, each of the first and second sections  3  and  4  is an open frame adapted for a patient&#39;s belly to depend therethrough or an imaging table top  151  and  152 . In another further embodiment, the hinges  6  and  7  are spaced apart or otherwise adapted for a patient&#39;s belly to depend therebetween. In another further embodiment, the chest slide  43  is reversibly attachable to the section  3  or  4  of the patient support structure. In another further embodiment, there is no second end support  21  and the hinges  6  and  7  are passively moved by the cantilevered lifting mechanism. In yet another embodiment, the chest slide  43  is actively driven by an actuator or motor  61  that is synchronized with the angulation of the hinges  6  and  7  by a computer software program such as but not limited by controller  26 . Numerous variations are foreseen. 
     It is to be understood that while certain forms of the patient positioning support structure have been illustrated and described herein, the structure is not to be limited to the specific forms or arrangement of parts described and shown.