WO2004082522A2

WO2004082522A2 - Multi-axial positioning system for a surgically-implanted spinal support

Info

Publication number: WO2004082522A2
Application number: PCT/US2004/002497
Authority: WO
Inventors: Ian P. Murray
Original assignee: Murray Ian P
Priority date: 2003-01-31
Filing date: 2004-01-29
Publication date: 2004-09-30
Also published as: WO2004082522A3

Abstract

A surgically-implanted spinal support having at least one screw (10) embedded in the bone of the patient’s spinal column. Clamps (12) held between yokes (18) (washers) mounted on the screw (10) and secured by nut (11) . A rod (16) received in slots in the clamps. The end connecting spaced-apart screws. A method of use is disclosed.

Description

MULTI-AXIAL POSITIONING SYSTEM FOR A SURGICALLY-IMPLANTED SPINAL SUPPORT

BACKGROUND OF THE INVENTION Field ofthe Invention The present invention relates to a surgical procedure for implanting a spinal support and more specifically to a multi-axial system which can be adjusted to the anatomy ofthe patient, reducing the time required for surgery and reducing stress on the patient. Description of Related Art

Spinal disorders such as degenerative discs, stenous, trauma, scoliosis, kyphosis and spondylolisthesis are treated by surgical procedures which require screws in the bone portion of the spine connected to a length of rod which is bent to conform to the spinal anatomy ofthe patient. Various devices and techniques have been proposed which require bending ofthe rod in the operating room to provide the required anatomical support for the particular patient. In most available systems, however, bending is mandatory. These bends generate stress concentrations and potential failure points which inherently weaken the system. The normal body movements of he patient, over time, may cause the rod or rods to break due to metal fatigue, and a catastrophic failure ofthe rod will require a further spinal procedure and much risk and inconvenience to the patient. This is a serious problem alleviated by the present invention with the use of pre-formed rods. Moreover, the competitive rods are repeatedly bent by the surgeon (to accommodate the particular patient's anatomy) in a sort of "coarse and fine" or "cut and try" procedure, which is somewhat time-consuming. Minutes in the operating room translate into many dollars of cost, and even more significantly, a shortened surgical procedure means less patient exposure and risk, a lower infection rate, less anesthesia, and less blood loss for the patient. U.S. Patent No. 6,478,798 to Howland discloses an anchor screw assembly in which the stress and load is placed on a pin and the rod is offset from the axis ofthe anchor screw.

An improved system is required which reduces the time required for the surgeon to perform the procedure, requires less bending of rods, is less costly, reduces stress and trauma to the patient and wherein the location ofthe anchor screw is determined by the- anatomy ofthe patient rather than by the nature and location ofthe rod. SUMMARY OF THE INVENTION It is an object ofthe invention to provide a surgically-implanted spinal support which conforms to the anatomy ofthe patient.

It is a further object ofthe invention to provide a multi-axial positioning system which is aligned and adjusted by the surgeon during surgery with minimum adjustments and in reduced time.

It is another object ofthe invention to provide a less costly system as compared to present systems.

It is still another object ofthe invention to provide a kit containing a mimmum number of components for use by the surgeon in the procedure.

In accordance with the teachings ofthe present invention, there is disclosed a surgically- implanted spinal support, wherein at least two screws are embedded into a patient's spinal column. Each screw has an axis and each screw carries a pair of clamps tightened by a nut on each screw. The clamps include an upper clamp and a lower clamp having respective cooperating semi-cylindrical slots for receiving a rod therebetween. The rod has an axis. The improvement is a pair of yokes (washers) carried by each screw and including an upper yoke disposed above and adjacent to the upper clamp and further including a lower yoke disposed below and adjacent to the lower clamp. Each ofthe yokes has a substantially semi-cylindrical seat, and each of the clamps has a substantially semi-cylindrical complementary outer surface engaging the seats ofthe respective yoke. In this manner, the clamps may swivel in either direction and to a limited degree about an axis which is substantially perpendicular to the axis of the respective screw.

In further accordance with the teachings ofthe present invention, there is disclosed a multi-axial positioning system for a surgically implanted spinal support embedded into a patient's spinal column. The system has at least one screw, a lower yoke having a semi- cylindrical seat having a first opening therein and an upper yoke having a semi-cylindrical seat having a second opening therein. The screw is received in the first and second openings and projects above the upper yoke. The system has an upper clamp and a lower clamp. Each clamp has a planar inner surface, the inner surface being disposed opposite one another. Each clamp has a semi-cylindrical outer surface, the opposed clamps forming a cylindrical outer surface.

Each clamp has a through opening therein, the opposed clamps being disposed in the respective semi-cylindrical seat of he upper yoke and the lower yoke. The screw passes through the through openings in the clamps wherein the clamps may swivel in either direction to a limited degree within the upper yoke and the lower yoke thereby providing a first axis of positioning. Each clamp has an end distal from the screw. A semi-cylindrical slot is formed in each clamp near the respective end of each clamp. A rod having a length is adjustably received in the semi- cylindrical slots in the clamps, thereby providing a second axis of positioning. Each clamp has a length between the screw and the rod. The length ofthe clamp is selected to be adapted to the anatomy ofthe patient's spinal column, thereby providing a third axis of positioning. Each screw is adjustably embedded at a preselected angle and depth into the patient's spinal column thereby providing a fourth axis of positioning.

In still further accordance with the teachings ofthe present invention there is disclosed a multi-axial positioning system for a surgically implanted spinal support anchored in the bone portion of a patient's spine. A first axis of positioning is formed by a pair of opposing clamps. Each clamp has a semi-cylindrical outer surface and a through opening formed therein. A screw is received in the through openings, wherein the clamps may swivel in either direction and to a limited degree with respect to the screw. A second axis of positioning is formed by a rod, the rod being movably received in a respective slot formed in an end of each ofthe clamps distal from the screw. A third axis of positioning is formed by a length of each clamp between the screw and the distal end ofthe respective clamp. A plurality of clamps are provided, each pair of clamps having a length different from the other pairs of clamps. A fourth axis of positioning is formed by the screw being adjustably anchored at a preselected angle and depth into the bone portion ofthe patient's spine.

Additionally, in accordance with the teachings ofthe present invention, there is disclosed a spinal surgical procedure in an operating room for implanting a spinal brace between spaced- apart vertebrae. A plurality of spaced-apart screws or other fasteners are anchored in the bone portion of a patient's spine. The screws carry respective clamping means for retaining a rod serving as a brace between vertebrae. The improvement is a multi-axial positioning system for the respective clamps, thereby minimizing the number of loose parts on the sterile field in the operating room, thereby facilitating a quick, convenient and easier implant ofthe spinal brace by the surgeon, and thereby involving substantially less time and hence less risk to the patient in the operating room while substantially reducing overall costs. Also, in accordance with the teachings ofthe present invention, there is disclosed a method of surgically implanting a spinal support in a bone portion of a spine of a patient. There is provided a plurality of screws, a plurality of pairs of clamps, the pairs of clamps having lengths different from other pairs of clamps, a plurality of upper yokes and a plurality of lower yoke, a plurality of nuts, and a plurality of rods, the rods having differing lengths and differing curvature. The patient is prepared for surgery. The patient is incised to expose the bone portion ofthe spine ofthe patient which is in need of repairs. At least two screws are inserted into the bone portion at a spaced-apart distance, a depth and an angle required to treat the patient. Lower yokes are disposed on each ofthe screws. A selected pair of clamps are disposed on each ofthe screws. Each pair of clamps is seated in a respective lower yoke. Upper yokes are disposed on the respective screws, each pair of clamps being seated in a respective upper yoke. A respective nut is disposed on each screw and partially tightened to secure the upper yoke loosely on the clamps. A selected rod is disposed into longitudinal slots on the ends ofthe clamps distal from the screws. The selected rod is moved axially within the longitudinal slots while swivelling the clamps within the upper and lower yokes such that the rod connects the at least two pairs of clamps and the rod is disposed substantially parallel to and conforming to the bone portion ofthe spine ofthe patient. The degree of swivel and length ofthe clamps are adjusted, the axial movement ofthe rod is adjusted to align the rod with the spinal column anatomy. The nut is tightened to secure the components in the desired relative positions. These and other objects ofthe present invention will become apparent from a reading of the following specification taken in conjunction with the enclosed drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a patient undergoing the surgically implanted spinal support. FIG. 2 is a perspective view of a spinal support of the prior art.

FIG. 3 is a perspective view of a different spinal support ofthe prior art. FIG. 4 is a perspective view ofthe spinal support ofthe present invention. FIG. 5 is an exploded perspective view ofthe screw, lower yoke, lower clamp, upper clamp, upper yoke, nut and rod. FIG. 6 is a side elevation view ofthe lower yoke.

FIG. 7 is a bottom plan view ofthe lower yoke. FIG. 8 is a top plan view ofthe lower yoke.

FIG. 9 is an end view ofthe lower yoke.

FIG. 10 is a side elevation view ofthe upper yoke.

FIG. 11 is a top plan view ofthe upper yoke. FIG. 12 is a bottom plan view ofthe upper yoke.

FIG. 13 is an end view ofthe lower yoke.

FIG. 14 is a side elevation view ofthe nut.

FIG. 15 is a top plan view ofthe nut.

FIG. 16 is a top plan view of a clamp. FIG. 17 is an end view ofthe clamp of FIG. 16.

FIG. 18 is a cross-section view taken across the lines 18-18 of FIG. 16.

FIG. 19 is a bottom plan view of he clamp of FIG. 16.

FIG. 20 is a front elevation view ofthe yokes holding the clamps on the screw.

FIG., 21 is a top plan view of FIG. 20. FIG. 22 is a cross-section view taken across the lines 22-22 of FIG. 21.

FIG. 23 is a side elevation view ofthe yokes holding the clamps on the screw.

FIG. 24 is a top plan view of FIG. 23.

FIG. 25 is a cross-section view taken across the lines 25-25 of FIG. 24.

FIG. 26 is a perspective view ofthe spinal support showing swiveling ofthe clamp 15° in a first direction.

FIG. 27 is the view of FIG. 22 showing swivelling ofthe clamp 15° in a second opposite direction.

FIG. 28 is a perspective view ofthe spinal support showing lateral movement ofthe clamp. FIG. 29 is a perspective view showing a tool crimping the upper yoke to the nut.

FIG. 30 is a perspective view ofthe crimped upper yoke securing the nut.

FIG. 31 is a perspective view of a kit containing components for use in an operating room. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, the patient is placed in the operating room (O.R.) so the surgical team has ready access to the patient's spine. An incision is made to expose the bone and the spinal support is surgically implanted as will be described. FIGS. 2 and 3 show spinal implants ofthe prior art. A plurality of spaced-apart screws

10 are driven into the bone portion ofthe patient's spinal column. The screws may be self- tapping. At the upper end of each screw 10, there is a spacer or clamp 12. The clamp 12 may be a pair of opposing members. The clamp 12 is secured to the screw 10 with a nut 14. A reinforcing rod 16 is mounted between the pair of clamps 12 and the rod 16 connects clamps on the spaced-apart screws. The rods 16 preferably are formed from titanium and usually are bent during the surgical procedure to conform to the anatomy ofthe individual patient. As previously noted, bending of the rods may result in failure ofthe surgical procedure. In most prior art spinal supports, the rods are 5-10 inches in length. The spinal implant usually consists of two rows of screws and rods, each row being on opposite sides ofthe spinal column. The spinal implant ofthe present invention, as shown in FIG. 4 differs from the prior art in that it is multi-axial in positioning as will be described.

As seen in FIG. 5, the lower portion ofthe body ofthe screw 10 has a relatively coarse thread and is threaded into the bone portion ofthe patient's spinal column. The screw 10 is inserted at a preselected angle to engage a significant thickness ofthe spinal column to assure a secure anchoring ofthe spinal implant. The angle may vary from patient to patient. Also, the depth ofthe insertion ofthe threaded portion ofthe screw 10 is determined by the anatomy of the patient since maximum depth is desired consistent with absence of potential injury to the spinal cord. A flange 22 is formed on the screw 10 immediately above the coarse threaded portion ofthe body ofthe screw 10. The portion ofthe body of he screw 10 immediately above the flange is formed having at least two parallel opposite sides 24 winch extend upwardly from the flange 22. The parallel sides 24 are oriented substantially parallel to the vertical axis ofthe spine ofthe patient. The remaining portion ofthe body ofthe screw 10 is formed with a thread 25 thereon from the upper reach ofthe parallel sides 24 to the end ofthe screw 10. Seated on the flange 22 is the lower yoke 18 (FIGS. 6-9). The lower yoke 18 has an opening 26 in the center. The opening 26 has at least two parallel opposite sides which cooperate with the body of the screw 10 such that when the screw 10 is received in the opening 26 in the lower yoke 18, the lower yoke 18 is supported by the flange 22 and the lower yoke 18 cannot rotate about the screw 10. Also, the orientation ofthe cooperating parallel opposite sides 24 ofthe body ofthe screw 10 and the opening 26 in the lower yoke, assure that the clamps 12 extend outwardly from the screw 10 in the desired direction as related to the anatomy ofthe patient as will be described. The lower yoke 18, has two arms 28 on opposite sides ofthe lower yoke 18, extending upwardly from the lower face ofthe lower yoke 18 foπning a substantially semi-cylindrical seat 30 within the lower yoke 18.

As shown in FIGS. 10-13, an upper yoke 20 has an opening 32 in the upper face, the upper body ofthe screw 20 is received in the opening 32. The upper yoke 20 has two arms 34 extending downwardly toward the arms 28 on the lower yoke 18. The arms 34 on the upper yoke 20 are on opposite sides ofthe upper yoke and form a substantially semi-cylindrical seat 36 which is opposite from the substantially semi-cylindrical seat 30 in the lower yoke 18. Together, there is formed a cylindrical seat between the lower yoke 18 and the upper yoke 20. In the top face ofthe upper yoke 20, there is formed a recess 38 which has a depth terminating in a radially inwardly projecting annular shelf.

The nut 14 has a threaded through opening 40 which cooperates with the threaded upper portion ofthe body of he screw. It is preferred that the nut 14 have at least one slot formed therein to facilitate tightening and loosening ofthe nut 14 with a tool such as a screwdriver.

When the nut 14 is threaded into the threaded upper body 25 ofthe screw 10, the nut is seated in the recess 38 in the top face ofthe upper yoke 20. The depth ofthe recess is approximately equal to the height ofthe nut 14 such that the top ofthe nut 14 is approximately flush with the top surface of the upper yoke 20. In a preferred embodiment the nut 14 is received in the recess 38 and the top surface ofthe upper yoke 20 is rolled to retain the nut 14. This is done during the manufacture ofthe components so there are fewer parts for the surgeon to account for during the surgical procedure.

FIGS. 18-19 show one ofthe clamps 12. The other clamp 10 is identical thereto and the clamps 12 are interchangeable. Each clamp 12 has an inner planar surface 44 and a semi- cylindrical outer surface 46. A through opening 48 is formed near an end of each clamp 12. The opening 48 has a diameter larger than the diameter ofthe body ofthe screw 10 and is elongated in axis perpendicular to the length ofthe clamp 12. Distal from the opening 48 in each clamp, a semi-cylindrical slot 50 is formed on the inner planar surface 44 perpendicular to the length of the clamp. Preferably, a plurality of ribs 52 are formed longitudinally in the slot 50 as will be explained. The clamps 12 are always provided as a pair, each member having the same length. However, the length ofthe clamps 12 may be varied so that longer pairs and shorter pairs are available. This provides a flexibility to the positioning ofthe clamps 12 to better conform to the anatomy ofthe patient.

As shown in FIGS. 20-25, the clamps 12 are disposed with the planar surfaces 44 adjacent to one another, the respective openings 48 aligned and the semi-cylindrical slots 50 opposed to one another forming a cylindrical opening distal from the screw 10. Preferably, the imier surfaces ofthe clamps have roughened to provide friction between the surfaces and to deter movement.

A length ofthe rod 16 is received in the cylindrical opening formed between the slots in the distal ends ofthe clamps (FIG. 4). The rod 16 is connected to the respective clamps 12 on the spaced-apart screws 10. Preferably, the rod 16 has a plurality of ribs formed thereon which extend longitudinally the length ofthe rod 16 and are circumferentially around the rod 16. The ribs on the rod 16 cooperate with the ribs 52 in the slot 50 on the clamps 12 such that rotational movement ofthe rod 16 with respect to the clamps is prevented. During the surgical procedure the rod 16 is placed in the lower clamp 12 before the upper clamp is secured which reduces the time ofthe operation and greatly simplifies the disposition ofthe components. Further the rods preferably have a length of about 4 inches and are provided as a set, each rod 16 having a different pre-bent curvature (with different radii). The purpose is to eliminate or to minimize the bending ofthe rod in the operating room during the surgical procedure.

Because ofthe cylindrical form ofthe adjacent clamps 12 disposed within the cylindrical seat between the upper yoke 20 and the lower yoke 18 and the elongated opening 48 in each clamp, the pair of clamps can be swivelled in either direction within the cylindrical seat (FIGS. 26-27). The swivel action is about an axis which is substantially perpendicular to the axis ofthe screw 10. The clamps may swivel approximately 15° in either direction for a total excursion of approximately 30°. This swivelling ability provides an axis of positioning for the spinal support to adapt the spinal support to the anatomy ofthe patient.

Also, because the through openings 48 in the clamps 12 have a diameter greater than the diameter ofthe screw 10, the clamps 12 may be moved, to a limited extent, in a plane perpendicular to the axis ofthe screw 10. This incremental sliding movement provides a "fine tuning" to the effective length of he pair of clamps 12 and provides for a further axis of positioning for the spinal support (FIG. 28).

If desired, after the spinal support system has been surgically implanted in the bone portion ofthe patient's spine, the nut 14 on each screw 10 may be locked in place to prevent any back-off. As shown in FIGS. 29-30, the upper yoke 20 is crimped with a tool 56 to produce an inward projection 58 within the slotted portion ofthe nut 14. This projection 58 prevents rotation ofthe nut 14.

The components minimally required in the operating room for performing the spinal surgery are shown in FIG. 31. A container 54 is provided having a plurality of screws 10, clamps 12, upper yokes 20, lower yokes 18, nuts 14 and rods 16 to constitute a kit. The yokes

18 and 20 may be provided separately or the lower yoke 18 may be preassembled or the screw 10 and the nut 14 may be retained in the upper yoke 20. The clamps 12 are pairs with different lengths and the rod 16 may have different curvatures. The number of individual components may be varied from kit to kit but the total number of components is significantly less than those required in presently available technology. This kit reduces the time the surgeon needs to perform the surgery. The reduction in the bending of he rods further shortens the time ofthe operation. As a result, there is less stress and trauma on the patient. Also, the costs for components is reduced as compared to present technology.

The procedure used by the surgeon is to have at least one kit 54 of components, or a plurality of individual components available in the operating room. The patient is prepared for the surgery and an incision is made to expose the bone portion ofthe patient's spine which is in need of repair. At least two screws 10 are inserted into the bone portion ofthe spine. The screws 10 are spaced apart a distance and are inserted at an angle and to a depth which is required to treat the individual patient. Lower yokes 18 are disposed on each screw 10. At least two pairs of clamps 12 are selected to be disposed on the at least two screws and the clamps are seated in the respective lower yokes 18. The lengths of each pair of clamps 12 is determined by the anatomy ofthe individual patient. An upper yoke 20 is disposed on each screw such that the pair of clamps 12 are seated in the upper yoke on each respective screw. A nut 14 is disposed on each screw 10 and the nut is partially tightened to secure the respective upper yokes loosely on the clamps 12. A rod 16 is selected which has a desired curvature. The rod 16 is disposed in semi-cylindrical slots 50 formed in the clamps distal from the screws. The rod 16 is moved axially within the semi-cylindrical slot while swivelling the clamps within the upper and lower yokes such that rod connects the at least two pairs of clamps. The rod 16 is disposed substantially parallel to and conforming to the bone portion ofthe spine ofthe patient. The rod may be further bent as required. The clamps and rod are axially positioned to align the rod with the bone portion ofthe patient's spine. The nut 14 is tightened to secure the components in the desired relative positions. If desired, the upper yoke may be crimped to prevent rotation ofthe nut.

The clamps 12 may be color coded to indicate different lengths ofthe clamps. The color code simplifies the procedure for the surgical team. Each member of a pair of clamps 12 is identical so that either clamp ofthe pair may be the upper or the lower clamp. This reduces the number of components and eliminates possible mismatch. The swivelling and sliding movement ofthe clamps provides axial positioning which was achieved in prior devices with a ball joint.

The present device is easy for the surgeon to use because the clamps may be separated to place the rod in the semi-cylindrical slot as opposed to a "C" shaped opening in prior devices.

The surgeon can place the rod in the open clamp and does not need to thread the rod tlirough the opening. Because of this, the location ofthe screw in the bone portion ofthe spine is determined by the anatomy ofthe patient. In prior devices, the curvature ofthe rod determined the location ofthe anchoring screw. The present device provides a multi-axial positioning system. The clamps may swivel in either direction between the upper yoke and the lower yoke. The rod has a length which may be adjustably received in the distal ends of he clamps. The clamps are provided in different lengths and may be selected to be adapted to the anatomy ofthe patient's spinal column. The clamps may further be slid perpendicularly with respect to the screw. Each screw is adjustably imbedded at a preselected angle and depth into the patient's spinal column.

Obviously, many modifications may be made without departing from the basic spirit of the present invention. Accordingly, it will be appreciated by those skilled in the art that within the scope ofthe appended claims, the invention may be practiced other than has been specifically described herein.

Claims

WHAT IS CLAIMED IS:

1. In a surgically-implanted spinal support, wherein at least two screws are embedded into a patient's spinal column, each screw having an axis and each screw carrying a pair of clamps tightened by a nut on each screw, the clamps including an upper clamp and a lower clamp having respective cooperating semi-cylindrical slots for receiving a rod therebetween, the rod having an axis, the improvement comprising a pair of yokes carried by each screw and including an upper yoke disposed above and adjacent to the upper clamp and further including a lower yoke disposed below and adjacent to the lower clamp, each ofthe yokes having a substantially semi-cylindrical seat, and each ofthe clamps having a substantially semi-cylindrical complementary outer surface engaging the seats ofthe respective yoke, such that the clamps may swivel in either direction and to a limited degree about an axis which is substantially perpendicular to the axis ofthe respective screw.

2. The spinal support of claim 1 , comprising at least a first screw and a second screw, the screws being spaced apart, the rod being connected between the respective clamps carried by the spaced-apart screws, the clamps on the first screw having a first length between the screw and the rod, the clamps on the second screw having a second length between the screw and the rod, wherein the first length may be different from the second length such that the rod may be disposed of at a preselected distance from each the first screw and the second screw as adapted to the anatomy ofthe patient's spinal column.

3. The spinal support of claim 1 , wherein the upper yoke has a recessed top surface, a securing nut being received in the recessed top surface.

4. The spinal support of claim 1, wherein the clamps may swivel approximately ±15° about the axis, ofthe screw.

5. A kit for surgically implanting a spinal support, comprising a plurality of sets of screws and cooperating clamps, a plurality of yokes, and a plurality of nuts together with at least one rod in accordance with the improvement of claim 1, wherein at least two ofthe sets have clamps of different lengths measured from the axis ofthe screw to the axis ofthe rod retained within the respective slots in the clamps, such that a multi-axial positioning system is provided for relatively-rapid surgical implantation ofthe rod with a substantially-reduced number of separate parts in the kit available in the operating room (O.R.), thereby providing the surgeon with increased flexibility while reducing the number of bends made in the rod during the surgical procedure to conform to the patient's spinal configuration, and thereby reducing the stress concentrations normally imposed on the rod during the bending procedure while reducing the time required for the surgical procedure in the O.R., reducing stress and trauma on the patient and being less costly.

6. The kit of claim 5, wherein the multi-axial positioning system comprises the swiveling ofthe clamps, the clamps having different lengths, and the rod being adjustable lengthwise ofthe axis thereof and within the cooperating slots in the respective clamps.

7. The kit of claim 6, wherein the clamps may swivel by approximately 15° in either direction for a total excursion of approximately 30°.

8. A multi-axial positioning system for a surgically implanted spinal support embedded into a patient's spinal column, comprising: at least one screw, a lower yoke having a semi-cylindrical seat having a first opening therein, an upper yoke having a semi-cylindrical seat having a second opening therein, the screw being received in the first and second openings and projecting above the upper yoke, an upper clamp and a lower clamp, each clamp having a planar inner surface, the inner surfaces being disposed opposite one another, each clamp having a semi-cylindrical outer surface, the opposed clamps forming a cylindrical outer surface, each clamp having a through opening therein, the opposed clamps being disposed in the respective semi-cylindrical seat ofthe upper yoke and the lower yoke, the screw passing through the through openings in the clamps wherein the clamps may swivel in either direction to a limited degree within the upper yoke and the lower yoke thereby providing a first axis of positioning, each clamp having an end distal from the screw, a semi-cylindrical slot being formed in each clamp near the respective end of each clamp, a rod having a length being adjustably received in the semi-cylindrical slots in the clamps, thereby providing a second axis of positioning, each clamp having a length between the screw and the rod, the length of the clamp being selected to be adapted to the anatomy ofthe patient's spinal column, thereby providing a third axis of positioning, and each screw being adjustably embedded at a preselected angle and depth into the patient's spinal columns thereby providing a fourth axis of positioning.

9. The multi-axial positioning system of claim 8, wherein the through opening in each clamp is elongated along a longitudinal axis of each clamp such that the clamps may be further slidably moved perpendicularly with respect to the screw thereby making incremental changes to the effective length ofthe clamps in the third axis of positioning.

10. A multi-axial positioning system for a surgically implanted spinal support anchored in the bone portion of a patient's spine comprising: a first axis of positioning being formed by a pair of opposing clamps, each clamp having a semi-cylindrical outer surface and a through opening formed therein, a screw being received in the through opening, wherein the clamps may swivel in either direction and to a limited degree with respect to the screw, a second axis of positioning being formed by a rod, the rod being movably received in a respective slot formed in an end of each ofthe clamps distal from the screw, a third axis of positioning being formed by a length of each clamp between the screw and the distal end ofthe respective clamp, a plurality of clamps being provided, each pair of clamps having a length different from the other pairs of clamps, a fourth axis of positioning being formed by the screw being adjustably anchored at a preselected angle and depth into the bone portion ofthe patient's spine.

11. In a spinal surgical procedure in an operating room ("O.R.") for implanting a spinal brace between spaced-apart vertebrae wherein a plurality of spaced-apart screws or other fasteners are anchored in the bond portion of a patient's spine, and wherein the screws carry respective clamping means for retaining a rod serving as a brace between vertebrae, the improvement comprising a multi-axial positioning system for the respective clamps, thereby minimizing the number of loose parts on the sterile field in the O.R., thereby facilitating a quick, convenient and easier implant of the spinal brace by the surgeon, and thereby involving substantially less time and hence less risk to the patient in the O.R. while substantially reducing overall costs.

12. A method of surgically implanting a spinal support in a bone portion of a spine of a patient comprising the steps of: providing a plurality of screws, a plurality of pairs of clamps, the pairs of clamps having lengths different from other pairs of clamps, a plurality of upper yokes and a plurality of lower yokes, a plurality of nuts, and a plurality of rods, the rods having differing lengths and differing curvature, preparing the patient for surgery, incising the patient to expose the bone portion ofthe spine ofthe patient which is in need of repair, inserting at least two screws into the bone portion at a spaced-apart distance, a depth and an angle required to treat the patient, disposing lower yokes on each ofthe screws, disposing a selected pair of clamps on each ofthe screws, each pair of clamps being seated in a respective lower yoke, disposing upper yokes on the respective screws, each pair of clamps being seated in a respective upper yoke, disposing a respective nut on each screw and partially tightening the nut to secure the respective upper yoke loosely on the clamps, disposing a selected rod into semi-cylindrical slots on the ends ofthe clamp distal from the screws, moving the selected rod axially within the semi-cylindrical slots while swivelling the clamps within the upper and lower yokes such that the rod connects the at least two pairs of clamps and the rod is disposed substantially parallel to and conforming to the bone portion ofthe spine ofthe patient, adjusting the degree of swivel and length ofthe clamps, adjusting the axial movement ofthe rod to align the rod with the bone portion ofthe spine and tightening the nut to secure the components in the desired relative positions.