EP2146656A1

EP2146656A1 - Implant insertion and alignment system

Info

Publication number: EP2146656A1
Application number: EP08747256A
Authority: EP
Inventors: Jennifer Diederich; Noelle Dye; Jennifer Mclaughlin; Arnold Oyola; Terrance Wong
Original assignee: Theken Spine LLC
Current assignee: Theken Spine LLC
Priority date: 2007-04-30
Filing date: 2008-04-30
Publication date: 2010-01-27
Also published as: WO2008134758A1

Abstract

A surgical system may be provided for a surgical procedure such as spinal surgery. The surgical system may include a spinal implant insertion system (100) having a first implant inserting tool (400 A) for inserting a first spinal implant (30 A), a second implant inserting tool (400 B) for inserting second spinal implant (30 B), and an aligner (700) for aligning the first and second spinal implants to a center of rotation region.

Description

IMPLANT INSERTION AND ALIGNMENT SYSTEM

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from co-pending and commonly assigned U.S.

Provisional Patent Application Serial Number 60/914,988, entitled "Alignment Insertion Instrument" by Jennifer Diederich, filed April 30, 2007; Provisional Patent Application Serial Number 60/914,975 entitled "Extension Guide Assembly" by Jennifer Diederich, filed April 30, 2007; Provisional Patent Application Serial Number 60/944,655 entitled "Alignment Insertion Instrument and Dual Driver" by Jennifer McLaughlin, filed June 18, 2007. This application is related to U.S. Patent Application 11/467,798, entitled "Alignment Instrument for Dynamic Spinal Stabilization Systems," filed on August 28, 2006; and U.S. Patent Application entitled "Offset Adjustable Dynamic Stabilization System" by Perriello al, filed September 10, 2007, Serial Number 11/852,821. All of the above applications are incorporated by reference herein in their entirety for all purposes.

BACKGROUND OF THE INVENTION

Field of the Invention

[0002] The present invention relates to skeletal stabilization and, more particularly, to aligning dynamic stabilization systems for the stabilization of human spines.

[0003] The human spine is a complex structure designed to achieve a myriad of tasks, many of them of a complex kinematic nature. The spinal vertebrae allow the spine to flex in three axes of movement relative to the portion of the spine in motion. These axes include horizontal movement (bending either forward/anterior or aft/posterior), rolling movement

(bending to either left or right side) and vertical movement (twisting of the shoulders relative to the pelvis).

[0004] In flexing about the horizontal axis into flexion (bending forward or in an anterior direction) and extension (bending backward or in a posterior direction), vertebrae of the spine must rotate about the horizontal axis to various degrees. The sum of all such movement about the horizontal axis produces the overall flexion or extension of the spine.

For example, the vertebrae that make up the lumbar region of the human spine move through roughly an arc of 15° relative to adjacent or neighboring vertebrae. Vertebrae of other regions of the human spine (e.g., the thoracic and cervical regions) have different ranges of movement. Thus, if one were to view the posterior edge of a healthy vertebra, one would observe that the edge moves through an arc of some degree (e.g., of about 15° in flexion and about 5° in extension if in the lumbar region) centered about a center of rotation. During such rotation, the anterior (front) edges of neighboring vertebrae move closer together, while the posterior edges move farther apart, compressing the anterior of the spine. Similarly, during extension, the posterior edges of neighboring vertebrae move closer together while the anterior edges move farther apart, thereby compressing the posterior of the spine. During flexion and extension the vertebrae move in horizontal relationship to each other providing up to 2-3 mm of translation.

[0005] In a normal spine, the vertebrae also permit right and left lateral bending.

Accordingly, right lateral bending indicates the ability of the spine to bend over to the right by compressing the right portions of the spine and reducing the spacing between the right edges of associated vertebrae. Similarly, left lateral bending indicates the ability of the spine to bend over to the left by compressing the left portions of the spine and reducing the spacing between the left edges of associated vertebrae. The side of the spine opposite that portion compressed is expanded, increasing the spacing between the edges of vertebrae comprising that portion of the spine. For example, the vertebrae that make up the lumbar region of the human spine rotate about an axis of roll, moving through an arc of around 10° relative to neighbor vertebrae throughout right and left lateral bending.

[0006] Rotational movement about a vertical axis relative is also natural in the healthy spine. For example, rotational movement can be described as the clockwise or counter-clockwise twisting rotation of the vertebrae during a golf swing. [0007] In a healthy spine, the inter-vertebral spacing between neighboring vertebrae is maintained by a compressible and somewhat elastic disc. The disc serves to allow the spine to move about the various axes of rotation and through the various arcs and movements required for normal mobility. The elasticity of the disc maintains spacing between the vertebrae during flexion and lateral bending of the spine, thereby allowing room or clearance for compression of neighboring vertebrae. In addition, the disc allows relative rotation about the vertical axis of neighboring vertebrae, allowing twisting of the shoulders relative to the hips and pelvis. A healthy disc further maintains clearance between neighboring vertebrae, thereby enabling nerves from the spinal chord to extend out of the spine between neighboring vertebrae without being squeezed or impinged by the vertebrae.

[0008] In situations where a disc is not functioning properly, the inter-vertebral disc tends to compress, thereby reducing inter-vertebral spacing and exerting pressure on nerves extending from the spinal cord. Various other types of nerve problems may be experienced in the spine, such as exiting nerve root compression in the neural foramen, passing nerve root compression, and enervated annulus (where nerves grow into a cracked/compromised annulus, causing pain every time the disc/annulus is compressed), as examples. Many medical procedures have been devised to alleviate such nerve compression and the pain that results from nerve pressure. Many of these procedures revolve around attempts to prevent the vertebrae from moving too close to one another in order to maintain space for the nerves to exit without being impinged upon by movements of the spine.

[0009] In one such procedure, screws are embedded in adjacent vertebrae pedicles and rigid rods or plates are then secured between the screws. In such a situation, the pedicle screws press against the rigid spacer that serves to distract the degenerated disc space, thereby maintaining adequate separation between the neighboring vertebrae to prevent the vertebrae from compressing the nerves. Although the foregoing procedure prevents nerve pressure due to extension of the spine, when the patient then tries to bend forward (putting the spine in flexion), the posterior portions of at least two vertebrae are effectively held together. Furthermore, the lateral bending or rotational movement between the affected vertebrae is significantly reduced due to the rigid connection of the spacers. Overall movement of the spine is reduced as more vertebrae are distracted by such rigid spacers. This type of spacer not only limits the patient's movements, but also places additional stress on other portions of the spine, such as adjacent vertebrae without spacers, often leading to further complications at a later date.

[0010] In other procedures, dynamic fixation devices are used. However, conventional dynamic fixation devices may not facilitate lateral bending and rotational movement with respect to the fixated discs. This can cause further pressure on the neighboring discs during these types of movements, which over time may cause additional problems in the neighboring discs. Furthermore, alignment of such dynamic fixation devices to enable a relatively natural range of motion while restricting undesirable motion is often difficult.

[0011] Accordingly, improvements are needed in insertion and alignment instruments for aligning dynamic systems that approximate and enable a fuller range of motion while providing stabilization of a spine.

SUMMARY

The Basic System:

[0012] Disclosed are embodiments of a spinal implant insertion system comprising a right implant inserting tool for inserting a right spinal implant, a left implant inserting tool for inserting a left spinal implant, and an aligner for aligning the right spinal implant and left spinal implant to a center of rotation region. Each of the right and left implant inserting tools include a handle means, an implant coupling means, the implant coupling means having a first end coupling means for coupling to one end of a spinal implant, a second end coupling means for coupling to the other end of the spinal implant, an angular distance adjusting means for adjusting an angle between the first end coupling means and the second end coupling means, the angular distance adjusting means including a first curved longitudinal member, and a second curved longitudinal member slidingly coupled to the first curved member, wherein the angular adjusting means is coupled to the handle means. Furthermore, the aligner has a first means to detachably couple to the right implant inserting tool, a second means to detachably couple to the left implant inserting tool, a means for angularly aligning the right implant inserting tool and the left implant inserting tool such that the right implant and a left implant are aligned to the center of rotation region.

[0013] In some of the above embodiments, the angular distance adjusting means of the right or left implant inserter further comprise an adjustment means for adjusting the position of the first curved member relative to the second curved member and the adjustment means further comprises a pinion means coupled to a distal end of an interior shaft coupled to the handle means and rotatably coupled to a rack gear means coupled to one of the first or second curved longitudinal members. [0014] In some of the above embodiments, the means for angularly aligning on the aligner further comprises a first curved longitudinal member, a second curved longitudinal member slidingly coupled to the first curved member, and a locking means for locking the position of the first curved member relative to the second curved member, and a target means for visually confirming alignment of the right spinal implant and left spinal implant.

[0015] In some of the above embodiments, the aligner includes a means showing relative distances from the implant inserters to determine the relative offset of the right spinal implant and left spinal implant.

[0016] In some of the above embodiments, there is also a means to adjust for the radial implantation positions of the left spinal implant and right spinal implant relative to the center of rotation region.

[0017] In some of the above embodiments, the handle means includes vertical markings for positioning the aligner marked on the shaft, a longitudinal bore defined within an exterior shaft such that the interior shaft can rotate within the longitudinal bore to transmit torque from a turning knob positioned at the proximal end of the handle to the pinion means.

Collet Driver Sub-System:

[0018] In some of the above embodiments, the first end coupling means or the second end coupling means each comprise a collet driver means detachably coupled to the respective end coupling means, wherein the collet driver means further includes a proximal end having a driver engagement means for receiving a torque from a driver, a distal end having a collet coupling means for detachably coupling to a collet of a spinal implant and transmitting the torque to the collet of a spinal implant, and a passage means for allowing a passage of a second driver through the collet driver means.

[0019] In some of the above embodiments, there is also included a first tubular coupler having a first plurality of projections adapted to couple to one side of a series of dovetail projections on the collet of a spinal implant, a second tubular coupler rotatably coupled to the first tubular coupler and having a second plurality of projections adapted to couple to the other side of the series of dovetail projections, and an interlinking means for rotating the first tubular coupler relative to the second tubular coupler between an unlocked position and a locked position, wherein in the unlocked position the first and second plurality of projections do not couple to both sides of the plurality of dovetail connections and in the locked position the first and second plurality of projections engage both sides of the plurality of dovetail projections.

[0020] In some of the above embodiments, there is dual driver means, the dual driver means comprising an internal shaft means including an internal proximal portion having an internal torque receiving engagement means, an internal distal portion having an internal distal torque transmission means adapted to couple to a torque receiving means of a bearing post of a spinal implant, an outer casing means slidingly and rotatably coupled to the internal shaft means, the outer casing means including an outer proximal portion having an outer torque receiving engagement means, and an outer distal end portion having an outer torque transmission means adapted to couple to the driver engagement means of the collet driver means.

The Po Iy head Holder Sub-System:

[0021] In some of the above embodiments, there is included a plurality of longitudinal guide means, wherein each longitudinal guide means has a longitudinal guide portion for slidingly engaging a portion of one of the implant coupling means of the right or left inserting tools, and a polyaxial screw head holding means detachably coupled to the longitudinal guide means.

[0022] In some of the above embodiments, there is a torque receiving means coupled to the polyaxial screw head holding means for receiving a torque from a driver, a first arm coupled to the polyaxial screw head holding means and having a first engagement means for engaging a polyaxial screw head, a second arm coupled to the polyaxial screw head holding means having a second engagement means for engaging the polyaxial screw head, an arm adjustment means coupled to the torque receiving means such that when torque is received the adjustment means adjusts the position of the first arm and second arm to allow the engagement means to engage the polyaxial screw head, and an access port defined within the longitudinal guide means for providing access to the torque receiving means for the driver. [0023] In some of the above embodiments, the arm adjustment means also includes a first pivot post, a second pivot post, a first cam surface coupled to the first arm, a second cam surface coupled to the second arm, an arm actuator means coupled to the torque receiving means such that as the torque receiving means is rotated, the arm actuator moves longitudinally to engaging the first and second cam surfaces causing the first and second arms to pivot about the first and second pivot posts, respectively.

[0024] In some of the above embodiments, there is included a screw driver means comprising an internal shaft means having a proximal portion and a distal portion, wherein the distal portion having a distal torque transmission means adapted to couple to a torque receiving means of a screw, an outer casing having a distal end portion wherein the distal end portion includes a screw shaft coupling means for coupling to a screw shaft while bypassing a polyaxial screw head coupled to the screw shaft, and an adjustment means for securing the torque transmission means to the torque receiving means of the screw.

[0025] In some of the above embodiments, the screw shaft coupling means further includes a C-clip means having a first end portion adapted for coupling to the outer casing and a second portion adapted for coupling to the shaft of the screw shaft.

Miscellaneous Subsystems:

[0026] In some of the above embodiments, there is included a decoupler means, the decoupler means comprising an elongated member having a proximal end portion and a distal end portion, an engagement means coupled to the distal end of the elongated member and adapted to releasably couple to an interior engagement surface of the collet driver means, wherein the engagement means moves from an unexpanded position to an expanded position, an actuator means coupled to the proximal end portion and to the engagement means such that the actuator means controls the movement of the engagement means from the unexpanded position to the expanded position.

[0027] In some embodiments, there is also disclosed spinal implant inserting tool comprising a handle means, an implant coupling means, the implant coupling means having a first end coupling means for coupling to one end of a spinal implant, the first end coupling means including a housing for a collet driver means, and a detachable collet driver means, a second end coupling means for coupling to the other end of the spinal implant, a housing for a collet driver means, and a detachable collet driver means, an angular distance adjusting means for adjusting an angle between the first end coupling means and the second end coupling means, wherein the angular adjusting means is coupled to the handle means and includes a first curved longitudinal member coupled to the first end coupling means, a second curved longitudinal member slidingly coupled to the first curved longitudinal member and coupled to the second end coupling means.

[0028] In some of the above embodiments, each of the right and left implants further comprises a first bearing post means, a first bushing rotabably coupled to the first bearing post means, a first member having a housing rotatably coupled to the first bushing, a second bearing post means, a second bushing rotabably coupled to the second bearing post means, a second member slidingly coupled to the first member and having a second housing rotatably coupled to the second bushing.

[0029] In some of the above embodiments, each of the right and left implants further comprises: a means for coupling to a first polyaxial screw head, a means for coupling to a second polyaxial screw head, and a means for allowing curved movement about a center of rotation region between the first polyaxial screw head and the second polyaxial screw head. [0030] In some of the above embodiments, there may also be a plurality of polyaxial screws, wherein each polyaxial screw includes a shaft having a distal and proximal end, a head coupled to the proximal end of the shaft, the head having temporary angular movement relative to the shaft about three axis, the head including a first groove for engaging the first arm defined within a side surface of the head, a second groove for engaging the second arm defined within a side surface of the head, and a lip radially extending the side surface of the head at a proximal end portion of the head. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following Detailed Description taken in conjunction with the accompanying drawings, in which:

[0032] FIG. IA illustrates a perspective view of an implant insertion and alignment system coupled to a portion of a spine;

[0033] FIG. IB depicts another perspective view of the implant insertion and alignment system of Fig. IA;

[0034] FIG. 1C illustrates a top posterior view of the spine with one possible embodiment of a pair of spinal implant devices coupled to a pair of adjacent vertebrae;

[0035] FIG. 2A illustrates a perspective view of one possible embodiment of an instrument delivering a screw to a vertebrae;

[0036] FIG. 2B illustrates an exploded view of the instrument of Fig. 2A;

[0037] FIG. 2C illustrates a cross-sectional view of a portion of the instrument of Fig.

2A;

[0038] FIG. 2D illustrates a detail perspective view of a portion of the instrument of

Fig. 2A and one possible embodiment of a c-clip;

[0039] FIG. 2E illustrates a partial assembly view of the instrument of Fig. 2A;

[0040] FIG. 3A illustrates an exploded view of one possible embodiment of a holder for a polyaxial screw head;

[0041] FIG. 3B illustrates a rear, cross-sectional view of the holder of Fig. 3A in a possible first position; [0042] FIG. 3C illustrates a top view of the holder of Fig. 3 A a pedicle screw with a polyaxial head in the first position;

[0043] FIG. 3D illustrates a rear, partial phantom view of the holder of Fig. 3A in a possible second position;

[0044] FIG. 3E illustrates a top view of the holder of Fig. 3 A a pedicle screw with a polyaxial head in the second position;

[0045] FIG. 4A illustrates an exploded view of a dual driver assembly;

[0046] FIG. 4B illustrates a cross-sectional view of the dual driver assembly of Fig.

4A;

[0047] FIG. 4C illustrates a perspective view of the dual driver assembly of Fig. 4A;

[0048] FIG. 5A illustrates a perspective view of one possible embodiment of an implant inserter assembly coupled to one possible embodiment of an implant;

[0049] FIG. 5B depicts an exploded view of the implant inserter assembly and implant of Fig. 5 A;

[0050] FIG. 5C depicts an exploded detail view of a portion of the implant inserter assembly of Fig. 5 A;

[0051] FIG. 6 A depicts an exploded view of one possible embodiment of a collet bushing assembly;

[0052] FIG. 6B depicts a perspective view of one possible embodiment of a component which may be incorporated into the collet bushing assembly of Fig. 6A;

[0053] FIG. 6C depicts a perspective view of one possible embodiment of another component which may be incorporated into the collet bushing assembly of Fig. 6A;

[0054] FIG. 6D depicts a perspective view of the collet bushing assembly of Fig. 6A; [0055] FIG. 6E depicts a cross-sectional view of the collet bushing assembly of Fig.

6A;

[0056] FIG. 6F illustrates a top view of the collet bushing assembly of Fig. 6A in a possible first position;

[0057] FIG. 6G illustrates a side view of the collet bushing assembly of Fig. 6A in a possible first position;

[0058] FIG. 6H illustrates a top view of the collet bushing assembly of Fig. 6A in a possible second position;

[0059] FIG. 61 illustrates a side view of the collet bushing assembly of Fig. 6A in a possible second position;

[0060] FIG. 6J illustrates a side view of the collet bushing assembly of Fig. 6A in a locked position;

[0061] FIG. 7A depicts a perspective view of one possible embodiment of a left-right alignment device;

[0062] FIG. 7B depicts an exploded view of the left-right alignment device of Fig.

7A;

[0063] FIG. 8A depicts an exploded view of one possible embodiment of a decoupling instrument; FIG. 8B illustrates a cross-sectional view of the decoupling instrument of Fig. 8 A in a possible first position;

[0064] FIG. 8C illustrates a cross-sectional view of the decoupling instrument of Fig.

8A in a possible second position;

[0065] FIG. 9A-B illustrate perspective views of one possible embodiment of a pedicle screw inserted over a guidewire; [0066] FIG. 1OA illustrates a perspective view of an extension guide exploded from a polyhead holder;

[0067] FIG. 1OB illustrates a perspective view of an implant inserter being guided along a pair of extension guide assemblies;

[0068] FIG. 1OC illustrates a perspective view of an implant inserter coupled to a spinal implant and a dual driver inserted into a collet bushing of the implant inserter;

[0069] FIG. 10D- 1OE illustrate cross-sectional views of a spinal vertebra showing centers of rotation of a pair of spinal implants and a desired common center of rotation;

[0070] FIG. 1 IA-I IB illustrate perspective views of a left-right aligner coupled to a shaft of an implant inserter;

[0071] FIG. 12A- illustrates a perspective view of a pair of implant inserters coupled to a left-right aligner;

[0072] FIG. 12B illustrates a perpective view of a pair of implant inserters coupled to a left-right aligner which is coupled to a locking member;

[0073] FIG. 13A illustrates a perspective view of a dual driver coupled to a collet bushing assembly of an implant inserter;

[0074] FIG. 13B illustrates a perspective view of a collet driver coupled to a collet bushing assembly of an implant inserter;

[0075] FIG. 14 illustrates a decoupler device inserted into a collet bushing assembly of an implant inserter; and

[0076] FIG. 15 illustrates a top posterior view of the spine with one possible embodiment of a pair of spinal implant devices coupled to a pair of adjacent vertebrae . DETAILED DESCRIPTION

[0077] Specific examples of components, methods, and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to limit the invention from that described in the claims. Well-known elements are presented without detailed description in order not to obscure the present invention in unnecessary detail. For the most part, details unnecessary to obtain a complete understanding of the present invention have been omitted inasmuch as such details are within the skills of persons of ordinary skill in the relevant art.

Alignment System 100 (Fig. 1)

[0078] Referring now to Figs. IA and IB, a perspective view is shown of one possible embodiment of an implant insertion and alignment system 100. Fig. IA shows the implant insertion and alignment system 100 coupled to a spine 10 and Fig. IB shows the implant insertion and alignment system 100 coupled to four bone anchors, such as pedicle screws 20A-20D. The spine 10 has been removed from Fig. IB for clarity purposes to better show implants such as the pedicle screws 20A-20D and a center of rotation 50 of one or more spinal implants 30A and 30B which may correspond to a natural center of rotation of a first and second vertebrae 12 and 14 of the spine 10. It is to be understood that other anchors may be used, such as other types of screws, plates or flexible rods, which have a means for dynamic stabilization of the spine 10 (not shown). The implant insertion and alignment system 100 may deliver and align the spinal implants 30A and 30B to the center of rotation 50. In certain emdodiments the center of rotation may be within a disc space between a pair of vertebrae, such as the vertebrae 12 and 14.

[0079] The implant insertion and alignment system 100 may comprise a first implant inserter instrument 400A , a second implant inserter instrument 400B, a left-right aligner 700 and four extension guide assemblies 11 OA- 11 OD . The extension guide assemblies 11 OA- HOD may couple directly or indirectly to a respective pedicle screws 20A-20D, which may each have a polyaxial head (not shown). In the embodiment illustrated, the extension guide assemblies 110A-110D may couple to respective polyhead holders 300A-300D, which may be coupled to the respective polyaxial head (not shown) of the pedicle screws 20A-20D. [0080] The first implant inserter instrument 400A may couple to the first spinal implant 30A and the first implant inserter instrument 400A and the implant 30A may be guided along the pair of extension guide assemblies HOA and HOB to an implantation site, such as a first vertebra 12 and a second vertebra 14 on one side of a spinous process of a spine 10. Once the first spinal implant 30A is guided to the implantation site, the first spinal implant 30A may couple directly or indirectly to the pedicle screws 2OA and 2OB. The pedicle screws 2OA and 2OB may have been previously implanted to the vertebrae 12 and 14, respectively. In a similar approach, the second implant inserter instrument 400B may deliver the second spinal implant 30B to couple to pedicle screws 2OA and 2OB implanted into the first and second vertebra 12 and 14 on an opposing side of the spinous process from the first spinal implant 30A. In certain embodiments the spinal implants 30A and 30B may be the same size; however, in other embodiments the spinal implants 30A and 30B may be of different sizes to accommodate variations in a patient's anatomy and a surgeons placement of the pedicle screws 20A-20D. The first and second implant inserters 400A and 400B may expand or contract the respective spinal implants 30A and 30B to properly insert and align the spinal implants 30A and 30B. In certain embodiments the spinal implants 30A and 30B may be expanded or contracted to bias the spinal implants 30A and 30B to allow either increased extension or increased flexion of the vertebrae 12 and 14 to which the spinal implant is coupled.

[0081] The first spinal implant 30A and the second spinal implant 30B may each have a unique center of rotation. A left-right aligner 700 may couple the first implant inserter 400A and the second implant inserter 400B. Installation of the left-right aligner 700 to the first implant inserter 400A and the second implant inserter 400B may align a center of rotation of the first implant 30A and a center of rotation of the second implant 30B to the common center of rotation 50. In some embodiments, the relative movement of the spinal implants 30A and 30B may be limited to a path within the intervertebral disc space as defined by the center of rotation 50. The center of rotation 50 may be stationary or may move within a disc space (between the vertebrae 12 and 14) in conjunction with movement of the vertebrae 12 and 14 to which the spinal implants 30A and 30B are coupled. Furthermore, the center of rotation 50 need not be a stationary point, but may follow a path on or through the disc space. For purposes of convenience, the term center of rotation may be used herein to refer to a specific point and/or a three dimensional area. [0082] Referring now to Fig. IC a posterior view of the spine 10 is shown illustrating the spinal implants 3OA and 30B aligned to the center of rotation 50. The spinal implants 30A and 30B may be locked or secured such that the spinal implants 30A and 30B remain aligned to the center of rotation 50 throughout various motions of the spine 10, such as flexion, extension, rotation and lateral bend. The spinal implants 30A and 30B may include one or more bearing posts 34A-34D to lock the spinal implants 30A and 30B such that one or more axis 4OA and 4OB of the spinal implant 30A and one or more axis 4OC and 4OD of the spinal implant 30B generally point to the center of rotation 50. The spinal implants 30A and 30B may also include one or more collets 32A-32D. The position of the center of rotation 50 may be adjusted by modifying the height of the spinal implants 30A and 30B relative to the respective bearing posts 34A-34D. The ability to adjust the height of the spinal implants 30A and 30B may account for variations or inconsistencies in the placement and insertion depth of pedicle screws 20A-20D (see Fig. IB). Once the proper position of the center of rotation 50 is determined, the final height of the spinal implants 30A and 30B may be locked by securing the collets 32A-32D to the respective bearing posts 34A-34D. [0083] As will be described later in detail, the implant insertion and alignment system

100 may comprise other instruments and implants to aid in inserting, securing, and aligning the pedicle screws 20A-20D, polyaxial heads 22A-22D, bearing posts 32A-32D, bushings 32A-D and spinal implants 30A and 30B (to stabilize the spine 10 and control various movements of the spine 10 (e.g. flexion, extension, rotation and lateral bending). For example, instruments may be provided to hold the polyaxial heads 22A-22D and insert the pedicle screws 20A-20D (see Fig. IB) into the first and second vertebrae 12 and 14. Other instruments may be provided to insert and lock bearing posts 34A-34D and collets 32A-32D.

Pedicle Screwdriver 200 (Fig. 2)

[0084] Referring to Fig. 2A, there is presented an assembly view of one embodiment of a pedicle screw driver 200 which may couple to the polyaxial head 22 of the pedicle screw 20 and may be used to advance the pedicle screw 20 into one or more vertebra of the spine 10. In the embodiment shown in Fig. 2A, the pedicle screw 20 may be advanced along a guide wire 60 to the pedicle insertion site at one or more vertebrae (shown in Fig. 2A as first vertebra 12 and second vertebra 14) with the aid of the pedicle screw driver 200. Alternatively, the pedicle screw driver 200 may deliver and advance the pedicle screw 20 without the use of a guide wire 60. In the embodiment shown in Fig. 2A, the polyhead holder 300 has been pre -installed to the polyaxial head 22 of the pedicle screw 20. The screw driver 200 and its parts may be manufactured in whole or in part from stainless steel or other metals.

[0085] The pedicle screw driver 200 may be comprised of an inner shaft 201, an outer housing 260, a compression member 280, and a c-clip 290, extending generally along a longitudinal axis 203. The c-clip 290 may function to maintain engagement of a torque transfer feature 248 (not shown) of the inner shaft 201 of the pedicle screw driver 200 with a torque transfer feature (not shown) of the pedicle screw 20. The pedicle screw 20 may be secured to the pedicle screw driver 200 by a compressive force applied by the compression member 280 to the inner shaft 201 which when engaged with the torque transfer feature (not shown) of the pedicle screw 20 pushes the pedicle screw 20 against the c-clip 290 creating a firm hold on the pedicle screw 20 but leaving the polyaxial head 22 free to rotate. A handle 202 may also assist to advance the pedicle screw 20 into a prepared pedicle site of the spine 10 by applying a torque to the inner shaft 201.

[0086] Referring now to Figure 2B, there is presented an exploded view of one embodiment of a pedicle screw driver 200. In certain embodiments, the inner shaft 201 (not shown as a whole) may comprise an upper shaft 220 and a lower shaft 240. The upper shaft 220 may be a generally solid circular shaft that extends longitudinally (as shown in Fig. 2A). A first end portion 222 of the upper shaft 220 may comprise an adapter 224 which may couple to a handle 202 (as shown in Fig. 2A). A second end portion 226 of the upper shaft 220 may comprise an insert 228 dimensioned to be at least partially received by the lower shaft 240. The upper shaft 220 may be dimensioned to be at least partially received by the outer housing 260 and the compression member 280.

[0087] In certain embodiments, the lower shaft 240 may be a generally solid circular shaft that extends longitudinally. The lower shaft 240 may be dimensioned to slide at least in part within a first bore 264 and a second bore 265 of the outer housing 260. A first end portion 242 of the lower shaft 240 may comprise a receptacle 244 which may be a bore dimensioned to receive the insert 228 of the upper shaft 220. The insert 228 of the upper shaft 220 may couple to the receptacle 244 of the lower shaft 240 forming the inner shaft 201 (not shown as a whole). Also, the first end portion 242 of the lower shaft 240 may further comprise an enlarged portion 250 having a relatively larger outer diameter than the second bore 265 which may restrict the enlarged portion 250 from sliding within the second bore 265 of the outer housing 260. The insert 228 and the receptacle 244 may be attached in order to transfer rotation of the upper shaft 220 to the lower shaft 240. Such means of attachment may include press fitting, slip fitting, welding, adhesives, mechanical fasteners, adapters. A second end portion 243 of the lower shaft 240 may comprise a torque transfer feature 248 (e.g. a male or female torx or hex) which may be dimensioned to operate with a torque receiving feature (not shown) of the pedicle screw 20. The lower shaft 240 may be dimensioned to be at least partially received by the outer housing 260 and the compression member 280.

[0088] In certain embodiments, the outer housing 260 may be a tubular member having an inner wall 262 defining the first bore 264 and the second bore 265. The upper shaft 220 and the lower shaft 240 may slide in part within the first bore 264 allowing it to extend from the second end portion 270 of the outer housing 260.

[0089] Referring now to Fig. 2C, there is shown a cross sectional view of the interaction of the upper shaft 220, the lower shaft 240, the outer housing 260, and the compression member 280. A first end portion 266 of the outer housing 260 may comprise a gripping portion 268 comprising a section of the first end portion 266 which may be dimensioned so that an outer diameter of the gripping portion 268 is larger than the rest of the outer diameter of the outer housing 260. The gripping portion 268 may have features such as depressions or a roughened surface which may prevent slippage or increase the amount of friction between the pedicle screw driver 200 and the operator's hand. The first bore 264 of the outer housing 260 may comprise a threaded portion 276 and be dimensioned to receive at least partially the compression member 280. The second bore 265 may be dimensioned to receive the lower shaft 240, except that the second bore 265 may be dimensioned to prevent the enlarged portion 250 from sliding within it. [0090] The compression member 280 may comprise a tubular member extending longitudinally and having an inner wall defining a bore 281 which may be dimensioned to allow the entire upper shaft 220 to pass through it but may not allow the enlarged portion 250 of the lower shaft 240 to pass within it. A first end portion 282 of the compression member 280 may comprise a threaded section 284 which may be dimensioned to threadably engage the threaded section 276 of the inner wall 262 of the outer housing 260. The compression member 280 may be dimensioned to be at least partially received by the outer housing 260 such that the compression member 280 may at least partially receive the upper shaft 220, as shown in Fig. 2C. A second end portion 286 of the compression member 280 may comprise a turning knob 288 which may be dimensioned with an outer diameter large enough to prevent at least a portion of the second end portion 286 from being received by the outer housing 260.

[0091] The upper shaft 220 may slide within the compression member 280 and the outer housing 260 a distance constrained by how far into the bore 281 the threaded portion 284 of the compression member 280 has engaged the threaded section 276 of the inner wall 262 of the outer housing 260. The enlarged portion 250 of the lower shaft 240 may prevent the upper shaft 220 from sliding out of the compression member 280 and be further constrained by a ridge 283 on the inner wall 262 of the first bore 264 of the outer housing 260. When the compression member 280 is fully engaged into the outer housing 260, the second end 246 (not shown) may extend from the outer housing 260 to engage the torque transfer feature (not shown) on top of the pedicle screw 20.

[0092] Referring now to Figure 2D, there is shown a detailed view of a second end portion 270 of the outer housing 260 coupled to a polyaxial head 22 of the pedicle screw 20 and the c-clip 290 is shown exploded. The second end portion 270 of the outer housing 260 may comprise a neck 272 and a collar 274. The neck 272 may be dimensioned as a recessed cylindrical band which may receive at least a portion of the c-clip 290. The collar 274 may comprise a cylindrical band and be located along the outer housing 260 at the second end portion 270. The collar 274 may have a larger outer diameter than the neck 272 but a smaller diameter than a body portion of the outer housing 260 so that the collar 274 creates a ridge 278.

[0093] In certain embodiments, a c-clip 290 may be comprised of a connection ring

292, an extension portion 294, and a clip 296. The connection ring 292 may comprise at least a portion of a circular band having a diameter and a width that may allow the c-clip 290 to receive the second end portion 270 of the outer housing 260 at the neck 272. The clip 296 may comprise a gapped circular band having a diameter and a width to receive a neck 28 of the pedicle screw 20 just below the polyaxial head 22 of the pedicle screw 20 so that the clip 296 may not easily slip off the pedicle screw 20.

[0094] A portion of the connection ring 292 and a portion of the clip 290 may be connected to each other by an extension portion 294, forming a "c" shaped profile (shown as a backwards "c" in Fig. 2D). The extension portion 294 may have a length which may allow the connection ring 292 to couple to the outer housing 260 and the clip 290 to couple to the pedicle screw 20. Proximal to the connection ring 292, the extension portion 294 may comprise a ridge 298 which may be dimensioned to insert in a gap between the connection ring 292 and the polyaxial head 22 of the pedicle screw 20, and may allow rotation but restrain tilting of the polyaxial head 22. Further, the ridge 298 may assist in stabilizing the polyaxial head 22 while the screw driver 200 engages the pedicle screw 20. [0095] In certain embodiments, a snap ring 210 may be utilized to assist in holding the c-clip 290 to the outer housing. The snap ring 210 may comprise at least a portion of circular band having a diameter that may allow the snap ring 210 to grasp the neck 272. The snap ring 210 may be installed between the connection ring 292 of the c-clip 290 and the lower ridge 278 of the neck 272 of the outer housing 260 and may prevent the c-clip 290 from slipping off of the neck 272.

[0096] Referring to Figure 2E, the pedicle screw driver 200 may be configured to apply rotation and torque to the pedicle screw 20 in order to advance the pedicle screw 20 into one or more vertebrae of the spine. In certain embodiments, certain components may be pre-configured prior to use in the operating room. In the embodiment shown in Fig. 2E, the inner shaft 201 may be preconfigured to be slidingly coupled to the compression member 280. The second end portion 286 of the compression member may slidingly couple to the second end portion 226 of the upper shaft 220 which may pass through to the first end portion 222 of the compression member 280. The compression member 280 may be constrained from sliding off of the second end portion 226 of the upper shaft 220 by the enlarged portion 250 of the lower shaft 240. Also, in the embodiment shown in Fig. 2E, the c-clip 290 may be preconfϊgured to be attached to the outer housing 260 by placing the snap ring 210 on the ridge 278 (as shown in Fig. 2D) and slipping the connection ring 292 of the snap ring 290 over the collar 274 and onto the neck 272 (not shown) such that the connection ring 292 snaps into place and is constrained from axial translation.

[0097] The operator may prepare the pedicle screw driver 200 for use by first inserting the lower shaft 240 of the inner shaft 201 into the first bore 264 of the outer housing 260. The compression member 280 may then be threadably engaged to the outer housing 260. The pedicle screwdriver may be in an non-engaged configuration where the inner shaft 201 may slide within the outer housing 260 constrained only by the compression member 280. The operator may then couple the clip 296 of the c-clip 290 to the neck 28 of the pedicle screw 20 which may be coupled to polyaxial head 22. A ratchet handle 202 (as shown Fig. 2A) may be attached to the adapter 224 at the first end portion 222 of the upper shaft 220. The polyaxial head 22 may also be coupled to a polyhead holder assembly 300. The c-clip 290 may be placed as to not interfere with the connection between the polyhead holder assembly 300 and the polyaxial head 22. The operator may turn the turning knob 288 of the compression member 280 until the torque transfer feature 248 extends to and engages the torque transfer feature (not shown) of the pedicle screw 20. The operator may place the pedicle screw driver 200 in an engaged configuration by further turning the turning knob 288 until the compression member 280 presses the pedicle screw 20, by means of the connection between the inner shaft 201 with the torque transfer feature of the pedicle screw 20, against the clip 296 and creates a firm hold between the pedicle screw 20 and the pedicle screw driver 200. The polyaxial head 22 may remain free to rotate but may be constrained from tilting. Once configured, the pedicle screw 20 may receive the guide wire 60 (as shown in Fig. 2A) to assist in guiding the tip of the pedicle screw (not shown) to the pedicle insertion site. Alternatively, the pedicle screw 20 may be inserted without the use of a guidewire. Polyhead Holder 300 (Fig. 3)

[0098] Referring to Fig. 3A, there is presented an exploded view of one embodiment of a polyhead holder 300 which may couple or grasp at least a portion of a polyaxial head 22 (not shown). The polyhead holder 300 may comprise a body 302, a first actuator 320, a first arm 340, a second arm 390, a first post 360A, a second post 360B, a second actuator 380, and an adapter 399. The adapter 399 may be rotated to drive the first actuator 320 which may be coupled to the second actuator 380 such that the second actuator 320 is driven in a direction opposite that of the first actuator 320. The opposing motion of the first actuator 320 and second actuator 380 may interact to open and close the first arm 340 and the second arm 390. The polyhead holder 300 and its parts may be manufactured from stainless steel or other metals.

[0099] The body 302 may comprise a solid structure having a top surface 304, a bottom surface 306, a first side 308, and a second side 310. The top surface 304 may be essentially a flat surface forming an area which may comprise a first bore hole 312, a second bore hole 314, and a third bore hole 316 each extending from the top surface 304 through the body 302 to the bottom surface 306. The first bore hole 312 and second bore hole 314 may have a generally cylindrical shape dimensioned to receive the first post 360A and the second post 360B, respectively.

[00100] The polyhead holder 300 may be coupled to an extension guide assembly (not shown) which may help guide and secure other instruments (not shown) such as the pedicle screw driver 200 to the polyhead 22. The first bore hole 312 and the second bore hole 314 may also be dimensioned to at least partially receive a first post (not shown) and a second post (not shown) of the first extension guide assembly (not shown).

[00101] The body 302 may comprise a first pin hole 363 A (not shown) and a second pin hole 363B each extending laterally into an outside surface of the body 302. The first pin hole 363A (not shown) and a second pin hole 363B may intersect the first bore hole 312 and second bore hole 314, respectively. The first pin hole 363A (not shown) and a second pin hole 363B may be dimensioned to receive a first pin 362A and a second pin 362B, respectively. The first pin 362A and the second pin 362B may pass into a pin hole 364A of the first post 360A and a pin hole 364B of the second post 360B, respectively, to couple first arm 340 and second arm 390, respectively, to the body 302. The first bore hole 312, the second bore hole 314 and the third bore hole 316 may be arranged along the top surface 304 so that the third bore hole 316 is generally between the first bore hole 312 and second bore hole 314 flank the third bore hole 316.

[00102] The third bore hole 316 may be dimensioned to at least partially receive the second actuator 380 and have an inner surface that may restrain the second actuator 380 from rotation within the third bore hole 316. A portion of an inner surface of the third bore hole 316 may comprise a threaded section 318 (not shown). The threaded section 318 (not shown) may extend proximally near the bottom surface 306 longitudinally along the third bore hole 316 to nearly the midpoint between the top surface 304 and the bottom surface 306. The threaded section 318 (not shown) may be dimensioned to threadably engage at least a portion of the first actuator 320.

[00103] The first side 308 of the body 302 may be dimensioned to curve inwards in a generally concave shape. The second side 310 may be located opposite side of the body 302 from first side 308. The second side 310 may wrap into the first side leaving the interaction of the first side 308 and the second side 310 without corners. The concave shape of the first side 308 may be dimensioned to at least partially receive inserter 400 and the implant 30 curve around a shaft (not shown) connected to the pedicle screw 20 (not shown). [00104] The first actuator 320 may comprise a generally cylindrical shape extending along a longitudinal axis and have a first threaded section 322 and a second threaded section 324. The first threaded section 322 may extend generally from an upper end portion 326 of the first actuator 320 towards a lower end portion 328 of the first actuator 320. The second threaded section 324 may extend from the lower end portion 328 of the post towards the upper end portion 326. The first actuator 320 may further comprise a non-threaded region between the two threaded sections 322 and 324..

[00105] The upper end portion 326 of the first actuator 320 may further comprise a connection portion 330. The connection portion 330 may comprise a means for rigidly connecting the upper end portion 326 to the adapter 399. In the embodiment shown, the means is a lateral bore hole 305 in adapter 399 and a lateral bore hole 307 in the connection portion 330 both dimensioned to receive a third pin 303. The adapter 399 may comprise a torque-receiving element 385 comprising, for example, a torx, a hex, or a square. The adapter 399 may be permanently press fitted or welded to the connection portion 330 by receiving the third pin 303.

[00106] The lower end portion 328 of the first actuator 320 may comprise a tapered section 332. The tapered section 332 may comprise a cylindrical shape that tapers to a blunt conical shape and points away from the upper end portion 326 of the first actuator 320. [00107] The first arm 340 and the second arm 390 may be configured to be placed around at least a portion of the polyaxial head 22 (not shown) of the pedicle screw 20 (not shown). It is to be understood that the second arm 390 may be a mirror image of the first arm 340, such that the features of the second arm 390 may be referred to as complementary features of the first arm 340. The first arm 340 and second arm 390 of the polyaxial head holder 300 may be comprised of a fulcrum portion 346, 396, respectively, which may each define a bore 347, 397, respectively, dimensioned to receive the first post 360A and the second post 360B, respectively. The fulcrum portion 346, 396 may act as a rotation point for a grasping portion 344 and 394 and a leverage portion 348, 398 of the first arm 340 and the second arm 390, respectively.

[00108] The grasping portion 344, 394 may comprise a rigid member which may rotate about the rotation point located in the fulcrum portion 346, 396 of the first arm 340 and the second arm 390, respectively. A curved inner wall 342, 392 of the grasping portion 344, 394, respectively, may further comprise locking features 350, 391 dimensioned to fit the locking features of the polyaxial head 22 of the pedicle screw 20 (not shown). The locking feature 350, 391 may be comprised of flanges and recesses designed to fit corresponding recesses and notches of the polyaxial head 22 of the pedicle screw 20 (not shown). [00109] The second actuator 380 may be comprised of a first elongated member 382, a second elongated member 384, and a middle member 386. The first elongated member 382 and second elongated member 384 may each comprise generally a solid cylinder shape extending longitudinally. The middle member 386 may comprise generally a cylinder shape having a threaded bore 389 extending longitudinally and dimensioned to receive and couple to the first threaded section 322 of the first actuator 320. The first elongated member 382, the second elongated member 384 and the middle member 386 may all be rigidly connected and may comprise one unit. The middle member 386 may be flanked by the first elongated member 382 and second elongated member 384 so that the first elongated member 382 and the second elongated member 384 are positioned generally positioned on opposite sides from each other along a circumference of the middle member 386. The second actuator 380 may be dimensioned to be received by the third bore hole 316 of the body 302. [00110] The first post 360A and the second post 360B may each comprise generally a solid cylindrical shape dimensioned to be at least partially received by the first bore hole 312 and the second bore hole 314, respectively, of the body 302. The first post 360A and the second post 360B may be received by the first arm 340 and second arm 390, respectively, and may allow rotation of the first arm 340 and second arm 390. The first post 360A and the second post 360B may each further comprise pin holes 364A and 364B, respectively dimensioned to receive pins 362 A and 362B which may couple the first post 360A and the second post 360B to the first bore hole 312 and the second bore hole 314 to the first arm 340 and second arm 390, respectively.

[00111] The leverage portion 348 and 398 of the first arm 340 and second arm 390, respectively, may comprise a rigid member which may rotate about the rotation point located in the fulcrum portion 346, 396 of the first arm 340 and second arm 390, respectively. In the embodiment shown, the leverage portion 348, 398 of the first arm 340 and second arm 390, respectively, may extend from the fulcrum portion 346, 396 a relatively smaller distance than the grasping portion 344, 394 of the first arm 340 and second arm 390, respectively. This configuration may allow the leverage portion 348, 398 to act as the short arm of a lever and allow for improved tension or holding force on the polyaxial head 22 which may decrease disengagement.

[00112] Referring now to the embodiment shown in Figs. 3B, the leverage portion

348, 398 of the first arm 340 and second arm 390, respectively, may comprise a first push surface 352, 393 and a second push surface 354, 395. The first push surface 352, 393 may comprise a sloped surface. The orientation of the first push surface 352, 393 of the first arm 340 and second arm 390, respectively, may provide a platform to rotate the grasping portions 344 and 398 (not shown) of the first arm 340 and second arm 390, respectively, outwards away from one another. [00113] The second push surface 354, 395 of the first arm 340 and second arm 390, respectively, may comprise a generally flat surface whose orientation may provide a platform to rotate the grasping portions 344 and 394 (not shown) of the first arm 340 and second arm 390, respectively, inwards towards each other (as shown in Fig. 3D and 3E). The first push surfaces 352 and 393 and the second push surfaces 354 and 395 acted upon by a combination of the second actuator 380 and the first actuator 320 may control the movement and position of the first arm 340 and second arm 390 relative to the polyaxial head 22 (not shown) of the pedicle screw 20 (not shown).

[00114] The polyhead holder 300 may be configured so that the first actuator 320 and the second actuator 380 interact with the first push surfaces 352 and 393 and the second push surfaces 354 and 395 of the first arm 340 and second arm 390, respectively, to rotate the first arm 340 and second arm 390 either towards or away from each other. This mechanical open and close mechanism may allow for increased tension or holding force on the polyaxial head and may decrease disengagement.

[00115] The second actuator 380 may interact with the first push surfaces 352 and 393 and the second push surfaces 354 and 345B of the first arm 340 and second arm 390, respectively, to rotate the first arm 340 and second arm 390 outwards away from and inwards towards each other.

[00116] Referring now to Fig. 3B, the second actuator 380 and first actuator 320 may have an initial configuration which may allow the first actuator 320 and second actuator 380 to be installed to the body 302. The first actuator 320 may be threaded in the third bore hole 316 at the bottom surface 306 so that the first threaded section 322 of the first actuator 320 may threadably engage the threaded bore hole 389 of the middle member 386 of the second actuator 380. The second actuator 380 may be threadably coupled to the first actuator 320 at the threaded section 322 by inserting the second actuator from the top surface 304 at the third bore hole 316. The second actuator 380 may be advanced to an opposite end from the connection portion 330 (not shown) of the first actuator 320 so that the first elongated member 382 and second elongated member 384 of the second actuator 380 are generally near to the tapered section 332 of the post, as shown in Fig. 3B. The adapter 399 may be coupled to the connection portion 330 of the first actuator 320 by fastening the third pin 303 through the lateral bore hole 307 in the connection portion 330 and the lateral bore hole 305 in the adapter 399. The initial configuration may allow the polyhead holder 300 to be placed in an open position as shown in Fig. 3C.

[00117] Referring now to Figure 3C, the operator may prepare the polyhead holder

300 for use with the spinal implant placement and alignment system 100 (not shown) by placing the polyhead holder in its initial configuration, as described in Fig. 3B. The operator may receive the polyhead holder 300 pre-configured so that the first actuator 320 and second actuator 380 act in concert to control the positions of the first arm 340 and second arm 390. In the initial configuration, the tapered portion 387 and 388 of the first elongated member 382 and second elongated member 384, respectively, may be protrude from the body 302 further than the tapered section 332 of the first actuator 320. The result may be that the tapered portions 387 and 388 of the first elongated member 382 and second elongated member 384, respectively, engage the first push surfaces 352 and 393 of the first arm 340 and second arm 390, which may rotate about the rotation posts 360A and 360B. The result may be that the grasping portions 344 and 394 of the first arm 340 and second arm 390 expand. With the first arm 340 and the second arm 390 expanded, the operator may place the polyaxial head 22 between the grasping portions 344 and 394 so that the grooves 24 and 26 of the polyaxial head 22 line up and generally point from the groove 26 to the groove 24 towards the polyhead holder 300. The locking features of the polyaxial head 22 may also generally line up, but not yet engage, the locking features 350 and 391 of the first arm 340 and second arm 390, respectively. The locking features 350 and 391 may be dimensioned to receive the polyaxial head 22 in a specific orientation that corresponds to an orientation of the grooves 24 and 26 of the polyaxial head 22 so that the polyaxial head is secured. In other embodiments, the polyhead holder 300 may grab the polyaxial head 22 in any orientation. [00118] Referring now to Fig. 3D, the operator may control the position of the first arm and second arm relative to the polyaxial head 22 by attaching a shaft of a polyhead holder driver 40 to the adapter 399. A torque-transfer feature such as a torx or hex may couple to the torque-receiving element 385 of the adapter 399. The operator may rotate the polyhead holder driver 40 which may translate the first actuator 320 through the threaded section 318 (not shown) of the body 302 to drive the tapered section 332 of the first actuator 320 out of or into the body 302. The second actuator 380 may be restrained from rotation relative to the first actuator 320 by interaction of the inner surface of the third bore hole 316 and the rigidly connected first elongated member 382 and second elongated member 384. [00119] In one embodiment, the rotational movement of the adapter 399 may be converted into linear movement of the second actuator 320. The first actuator 320 may rotate in the threaded bore 389 of the middle member 386 of the second actuator 380. Turning the threads of the threaded section 322 of the first actuator may translate the second actuator 380 toward the top surface 304 of the body 302 as the tapered section 332 of the first actuator 320 is driven toward the bottom surface 306 of the body 302. Conversely, the tapered section 332 of the first actuator 320 may translate toward the top surface with a rotation of the adapter 399 as the second actuator translates toward the bottom surface 306. The threads of the first threaded section 322 may comprise a double lead thread. An equal amount of rotations of the first actuator 320 may result in increased linear movement of the tapered portions 387 and 388 of the first elongated member 382 and second elongated member 384, respectively, relative to the motion of the tapered section 332 of the first actuator 320. [00120] The tapered section 332 of the first actuator 320 may engage the second push surfaces 354 and 395 of the first arm 340 and second arm 390. The first tapered portion 387 and second tapered portion 388 of the first elongated member 382 and second elongated member 384 of the second actuator 380 may disengage and retract into the body 302. The result may be that the leverage portion 348 and 398 of the first arm 340 and second arm 390, respectively, are driven apart by the tapered section 332 of the first actuator 320 wedging between the first push surface 354 and second push surface 395. Referring now to Fig. 3E, the grasping portion 344 and 394 of the first arm 340 and second arm 390, respectively, may contract around the polyaxial head of the pedicle screw engaging the locking features 350 and 391 (not shown). The grasping portion 344 and 394 of the first arm 340 and second arm 390, respectively, of the polyhead holder 300 may lock into the polyaxial head 22 by communicating with the flanges and recesses of the polyaxial head 22.

[00121] Once the polyhead holder 300 is locked onto the polyaxial head 22, the operator may remove the polyhead holder driver 40 from the adapter 399. Removing the shaft of the polyhead holder driver 40 may reduce tissue stress and stretching and reduce the risk of necrosis. To unlock the polyhead holder 300 from the polyaxial head 22, the operator may again couple the shaft of the polyhead holder driver 40 to the torque receiving element 385 of the adapter 399 and rotated so that the first actuator 320 rises from the top surface 304 and the second actuator 380 engages the first push surfaces 352 and 393 which may rotate the grasping portions 344 and 394 of the first arm 340 and second arm 390, respectively, away from the polyaxial head 22, releasing the locking features 350 and 391 (not shown), respectively. As a result the polyhead holder 300 may be placed in its open position, as described above, and shown in Figs. 3B and 3C.

Dual Driver 800 (Fig. 4)

[00122] Referring now to Fig. 4A there is presented an exploded view of one embodiment of a dual driver 800 which may connect to the implant inserter assembly 400 by engaging at least a portion of the collet bushing assembly 500 in some configurations. The dual driver 800 may be used to transfer torque to another instrument or directly to a spinal implant 30 (not shown). The dual driver 800 may incorporate a first drive shaft 802 and a second drive shaft 804. In certain embodiments, the first drive shaft 802 may engage the spinal implant 30 (not shown) directly and the second drive shaft 804 may engage another instrument to transmit a torque to each. The dual driver 800 may have at least two configurations: a first configuration where the first drive shaft 802 engages the spinal implant 30 and the second driver shaft 804 may be locked in a position where the second drive shaft 804 is not engaged. In a second configuration, the first drive shaft 802 and the second drive shaft 804 are both engaged to the spinal implant 30 to transfer torque either directly or indirectly to one more locking members on an implant such as a post or collet of the spinal implant 30. In other embodiments, the dual driver 800 may further comprise a torque limiting device (not shown).

[00123] In certain embodiments, the first drive shaft 802 may be a generally solid cylindrical shaft that extends along a longitudinal axis 898. The first drive shaft 802 may have an adapter 810 at a first end portion 806 and a torque-transfer feature 816 (e.g. a male or female hex or torx) at a second end portion 808. The first adapter 810 may couple to a handle 896 (not shown) or a counter-torque device (not shown). The first drive shaft 802 may be dimensioned to be at least partially received by the second drive shaft 804. [00124] The first drive shaft 802 may further comprise a first depression 812 and a second depression 814 (not shown) which may each lie substantially longitudinally along the first drive shaft 802. The first depression 812 and the second depression 814 (not shown) may each be located substantially near to the first end portion 806 of the first drive shaft 802 and positioned generally diametrically opposite from each other but at the same relative distance along the first drive shaft 802. The first depression 812 and the second depression 814 (not shown) may each further comprise a first j -hook portion 838 and a second j -hook portion 840 (not shown) and be dimensioned to at least receive a first pin 834A and a second pin 834B which may ride within each depression 812, 814 (not shown), respectively, and hook into each j-hook portion 838, 840, respectively. The first j-hook portion 838 and the second j-hook portion 840 (not shown) may be oriented to work in concert to allow the second driver shaft to rotate at least partially relative to the first driver shaft 802 [00125] In certain embodiments, the second drive shaft 804 may be a tubular member extending along the longitudinal axis 898 having an inner wall defining a bore 818 which is dimensioned to at least partially receive the first drive shaft 802. The second drive shaft 804 may have a first end portion 820 having a first pin hole 830A and a second pin hole 830B (not shown), each dimensioned to receive the first pin 834A and second pin 834B, respectively. The first end portion 820 may further comprise a gripping member 842 which may allow an operator to hold, pull or rotate the second drive shaft 804 relative to the first drive shaft 802. The second drive shaft 804 may further comprise a second end portion 822 having a torque transfer feature 826 which may be dimensioned to couple and transmit a torque to other instruments (not shown).

[00126] The second drive shaft 804 may at least partially receive slidingly the first drive shaft 802 within the bore 818 so that the torque-transfer feature 816 and the adapter 810 may extend from the second end portion 822 and the first end portion 820, respectively, of the second drive shaft 804.

[00127] Referring now to Fig. 4B, there is shown a cross-sectional view of the dual driver 800. The dual driver 800 may be preconfigured prior to use by an operator in the operating room. The dual driver 800 may be manufactured such that the second drive shaft 804 may receive and be attached to the first pin 834A and second pin 834B at the first pin hole 830A and the second pin hole 830B, respectively, by known means such as press fitting, slip fitting, welding, adhesives, or fasteners. The first pin 834A and second pin 834B may slidingly secure the first drive shaft 802 within the second drive shaft 804 so that the first pin 834A and the second pin 834B insert into the first depression 812 and the second depression 814, respectively, of the first drive shaft 802. The second drive shaft 804 may be slidingly and rotatably coupled to the first drive shaft 802 so that the second drive shaft 804 may slide along the longitudinal axis 898 of the first drive shaft 802 along the first pin 834A and second pin 834B in order to adjust the relative distance of the torque transfer feature 826 of the second drive shaft 804 from the torque transfer feature 816 of the first drive shaft 802. The second driver shaft may also be locked in the first configuration so that the torque transfer feature 826 may not engage any other instrument while the torque transfer feature 816 of the first drive shaft 802 may engage a torque transfer feature (not shown) of the spinal implant 30 (not shown).

[00128] In the first configuration, the operator may slide the second drive shaft 804 longitudinally along the first depression 812 and the second depression 814 until the second drive shaft 804 reaches the first j-hook portion 838 (not shown) and the second j-hook portion 840 (not shown). The operator may use the dual driver 800 in the first configuration to slightly engage the implant 30 (not shown). The operator may rotate the gripping member 842 of the second drive shaft 804 so that the first pin 834A and second pin 834B engage and lock into the first j-hook portion 838 (not shown) and the second j-hook portion 840 (not shown), respectively. The torque transfer feature 826 of the second drive shaft 804 may now be spaced apart in the proximal direction from the torque transfer feature 816 of the first drive shaft 802 and at a distance to prevent the torque transfer feature 826 from engaging another instrument. The operator may now insert and engage the torque transfer feature 816 of the first drive shaft 802 with the torque transfer feature (not shown) of the spinal implant 30 (not shown).

[00129] Referring now to Fig. 4C, showing a perspective view of the dual driver 800 in the second configuration, , the torque-transfer feature 816 of the first drive shaft 802 may extend from the second end portion 822 of the second drive shaft 804 at a relative distance to the torque transfer feature 826 of the second drive shaft 804 such that the dual driver 800 may simultaneously engage and transmit a torque to the spinal implant 30 (not shown) and the torque receiving feature of another instrument (not shown). The operator may rotate the second drive shaft 804 by grabbing and rotating the gripping member 842. The operator may slide the second drive shaft 804 longitudinally along the first depression 812 and the second depression 814 (not shown) until the second drive shaft 804 is constrained from further longitudinal translation when the first pin 834A and second pin 834B (not shown) each reach an end portion (not shown) of the first depression 812 and the second depression 814 (not shown), respectively. The first depression 812 and the second depression 814 (not shown) along with the pins 834 A and 834B may angularly align the torque transfer feature 826 of the second drive shaft 804 to a torque transfer feature of another instrument. The torque-transfer feature 816 of the first drive shaft 802 may be in proximity to the torque transfer feature 826 of the second drive shaft 804 such that each torque-transfer feature 816, 826 may work in concert to engage the spinal implant 30 (not shown) and another instrument (not shown). The device in whole or in part may be manufactured from stainless steel or other metals.

[00130] The dual driver 800 may further secure one or more other spinal implants to the spine 10, not shown, as part of a method or system of inserting and aligning one or more spinal implants to a common rotational axis 50 (not shown).

Inserter Assembly 400 (Fig. 5)

[00131] Referring now to Figure 5A, there is presented a perspective view of one possible embodiment of a implant inserter assembly 400 which may deliver the spinal implant 30 to the implantation site and provide a connection to one or more components or instruments of the stabilization system such that the spinal implant 30 may be accurately aligned or oriented. The device in whole or in part may be manufactured from stainless steel or other metals. The implant inserter assembly 400 may comprise in part a handle 402, a first shaft 404, a first body alignment member 406, a second body alignment member 408, and a turning knob 464. The implant inserter 400 may also comprise a first driver assembly, and a second driver assembly which may comprise a first collet bushing assembly 500A and a second collet bushing assembly 500B. The first collet bushing assembly 500A and a second collet bushing assembly 500B may couple to the spinal implant 30 may adjust, align or secure the spinal implant 30. A more detailed description of the collet bushing assembly 500 is provided in reference to Figs. 6A through 6J.

[00132] The first collet bushing assembly 500A may be inserted into the first body alignment member 406 and may axially rotate freely in the first body alignment member 406. The second collet bushing assembly 500B may be inserted into the second body alignment member 408 and may axially rotate freely in the second body alignment member 408. [00133] The implant inserter assembly 400 may couple to the spinal implant 30 and may interact with other instruments and implants to aid in the delivery and securing of various spinal implants to stabilize the spine. Accordingly, the handle 402, the first shaft 404, the first body alignment member 406, the second body alignment member 408, the first collet bushing assembly 500A, and the second collet bushing assembly 500B may interrelate to provide for accurate placement and attachment of spinal implants.

[00134] The implant 30 shown in Figure 5 A may be one example of an embodiment to be used. Other implants which could be used with the various embodiments of the implant inserter instrument 400 are described in U.S. Patent Application 11/693,394, entitled "Dynamic Motion Spinal Stabilization System," filed on March 29, 2007; U.S. Patent Application 11/738,990, entitled "Dynamic Motion Spinal Stabilization System and Device," filed on April 23, 2007; U.S. Provisional Patent Application 60/831,879, entitled "Locking Assembly," filed on July 19, 2006; U.S. Provisional Patent Application 60/825,078, entitled "Offset Adjustable Dynamic Stabilization System," filed on September 8, 2006; U.S. Provisional Patent Application 60/826,807, entitled "Offset Adjustable Dynamic Stabilization System," filed on September 25, 2006; U.S. Provisional Patent Application 60/826,817, entitled "Offset Adjustable Dynamic Stabilization System," filed on September 25, 2006; U.S. Provisional Patent Application 60/883,314, entitled "Dynamic Linking Member for Spine Stabilization System," filed on January 3, 2007; the disclosures of which are incorporated by reference herein in their entirety for all purposes. [00135] Although only one type of implant is shown in Fig. 5 A, various embodiments of the present invention may incorporate and use a variety of implants where the implants are sized according to the physical distance between the patient's vertebrae. Each size of implant comprising a combination of different lengths, arcs or radii may correlate to a slider assembly comprising the first body alignment member 406 and the second body alignment member 408.

[00136] Thus, the implant inserter 400 may be incorporated into a system or kit containing a numerous pairs of implants, where each pair is sized to a predetermined range of lengths. Such a system may allow for proper alignment and sizing according to the patient's physical characteristics. In other embodiments, the implant inserter instrument 400 may also be incorporated into a system or kit containing guide wires, dilators, and/or retractors. Such a system is described in the commonly assigned U.S. Application No. 10/ 989715, entitled "Extension For Use With Stabilization Systems For Internal Structures" filed on November 16, 2004, which is incorporated herein by reference for all purposes.

[00137] Referring to Fig. 5B an exploded assembly view of one possible embodiment of the implant inserter assembly 400 is illustrated. One end portion of the shaft 404 may be inserted into the handle 402 using standard assembly techniques such as press fitting, hot staking, insert molding, threading, or pinning. The shaft 404 may be permanently attached to the handle 402 or the handle 402 may be removable from the shaft 404 using various adapters (not shown) which are well known to those skilled in the art. The shaft 404 may comprise a distal end portion 405 which may further comprise an attachment feature 403, (e.g. threads, detents, dovetail) to removeably couple the shaft 404 to the first body alignment member 406. The shaft 404 may attach to either the first body alignment member 406 or the second body alignment member 408.

[00138] The first shaft may further comprise a set of transverse grooves 492 which may be set into an outer surface of the first shaft 404. The set of grooves 492 may be demarcated to assist in the alignment of one or more implants (not shown) by indicating a height between the set of grooves 492 and the spinal implant 30. The height may be correlated between one or more implant inserters (not shown). [00139] In certain embodiments, the first body alignment member 406 may slidingly couple to the second body alignment member 408, so that the distance between the first body alignment member 406 and second body alignment members 408 may be adjusted. The first collet bushing assembly 500A and the second collet bushing assembly 500B may at least partially fit within and rotatably couple to the first body alignment member 406 and second body alignment member 408, respectively. The first collet bushing assembly 500A and the second collet bushing assembly 500B may also be free to slide axially relative to the first body alignment member 406 and second body alignment member 408, respectively. [00140] As shown in Fig. 5B, the first body alignment member 406 may have a first end portion 420 that is generally cylindrical in shape with an aperture 422 extending there through for receiving the first collet bushing assembly 500A. The first body alignment member 406 may have a second end portion 424 having a first curved elongated member 426 that is generally rectangular in cross section and extends longitudinally along a curved path. [00141] The second body alignment member 408 may have a first end portion 432 that is generally cylindrical in shape with an aperture 434 extending there through for receiving the second collet bushing assembly 500B. The second body alignment member 408 may have a second end portion 433 having a second curved elongated member 438 that is generally rectangular in cross section and has a track feature 444 (not shown) that is dimensioned to slidingly mate with a track feature 445 of the first curved elongated member 426. The second curved elongated member 438 may include a rack or gear feature 427 (not shown) that may aid in the adjustment of the first body alignment member 406 and second body alignment member 408. Alternatively, it is understood that this mechanism may be included on either 406 or 408.

[00142] As shown in Fig. 5B, the first collet bushing assembly 500A may be inserted at least partially through aperture 422 of the first body alignment member 406. The first collet bushing assembly 500A may have a rim 508A which allows the first collet bushing assembly 500A to rest on a rim 446 of the first end portion 420, as shown in Fig. 5A. The rim 508A may prevent the first collet bushing assembly 500A from passing completely through the aperture 434 during assembly or use. In certain embodiments the first collet bushing assembly 500A may rotate and axially slide freely within the aperture 422 of the first body alignment member 406. The second collet bushing assembly 500B may be inserted at least partially through an aperture 434 of the second body alignment member 408. The second collet bushing assembly 500B may have a rim 508B which may allow the second collet bushing assembly 500B to rest on a rim 448 of the second end portion 432, as shown in Fig.5A. The rim 508B may prevent the second collet bushing assembly 500B from passing completely through the aperture 434 during assembly or use. In certain embodiments, the second collet bushing assembly 500B may rotate freely and axially slide within aperture 434 of the second body alignment member 408.

[00143] Referring now to Fig. 5B, the implant inserter may further comprise a second shaft 456 which may have at a distal end portion a gear 454 of a rack and pinion mechanism 436 (not shown). The rack and pinion mechanism 436 (not shown) may provide a mechanism to control the sliding motion of the first body alignment member 406 and the second body alignment member 408. The implant inserter 400 assembly may further comprise a turning knob 464 which may be coupled to the second shaft 456 at a proximal end portion. The turning knob 464 may comprise a generally cylindrical shape extending longitudinally having, substantially, a first cylindrical portion 466 having a larger outer diameter than a second cylindrical portion 468. The second shaft 456 may couple to the second cylindrical portion 468 by an adapter 470 on a proximal end portion of the second shaft 456. The adapter 470 may have a non-circular cross section such as a hexagon or a square, to transfer torque. The adapter 470 may be received into a longitudinal bore 472 (not shown) in the turning knob 464, having a non-circular cross section that matches the adapter 470 in order to transfer torque, in the second cylindrical portion 468 and may be secured by a pin 474 that may run laterally through a lateral bore 476 in the second cylindrical portion 468 and a lateral bore 478 in the adapter 470.

[00144] The turning knob 464 and the second shaft 456 may be at least partially received by a first bore 480 defined by an inner wall in the handle 402. The first bore 480 may be dimensioned to at least partially receive the second cylindrical portion 468. The inner wall of the handle 402 may further define a second bore 484 dimensioned to at least partially receive the second shaft 456. It is to be understood that the turning knob 464 and the second shaft 456 may freely rotate within the first bore 480 of the handle 402 so that rotation of the turning knob 464 translates into rotation of the gear 454 of the rack and pinion mechanism 436 at a distal end portion of the second shaft 456.

[00145] Now referring to Figs. 5C, showing embodiments of the implant inserter assembly 400 in a perspective assembly view and a partially exploded view. In certain embodiments, the track feature 444 of the second curved elongated member 426 and the track feature 445 of the first curved elongated member 426 may have a male-female dovetail or a tongue and groove configuration to allow of the first body alignment member 406 and second body alignment member 408 to translate relative to one another. In the embodiment shown, a groove portion of the track feature 444 of the second curved elongated member 438 may receive a tongue portion of the track feature 445 of the first curved elongated member 426 and the relative position of the two curved elongated members 426 and 438 may be temporarily secured using a pin 461 press fit into the hole 460 or other mechanical means known to those skilled in the art. In certain embodiments, the arc of the first curved elongated member and the second curved elongated member may correspond to an arc of the spinal implant 30 (not shown), an arc of a center of rotation, or the arc created when the spinal implant 30 (not shown) moves in relation to the center of rotation 50 (not shown). [00146] A housing 450 may be coupled to a top surface of the second curved elongated member 438 or, alternatively, to a top surface of the first curved elongated member 426. The housing may have a threaded aperture 452 that mates with the attachment feature 403 of the shaft 404,.

[00147] Referring to Fig. 5C, there is shown an exploded detail view of one possible embodiment of a portion of the rack and pinion mechanism 436 which may be incorporated in the implant inserter assembly 400. In certain embodiments, the implant inserter assembly 400 may incorporate a rack and pinion mechanism 436 to adjust the distance between the first curved elongated member 426 and the second curved elongated member 438 which may result in adjusting the length of the attached implant 30 (not shown). In Fig. 5C, certain components have been moved or cross-sectioned to aid in the description. One end portion of the housing 450 may be coupled to a top surface of the first curved elongated member 426 or alternatively to a top surface of the second curved elongated member 438 (as shown). Another end portion of the housing 450 may couple to the first shaft 404. The housing 450 may have walls which define a window 458 which may received a gear or pinion mechanism 436, such that the gear 454 is free to rotate within the window 458 of the housing 450. [00148] The first shaft 404 may comprise a tubular member extending along the longitudinal axis 498 having a bore 405 dimensioned to receive the second shaft 456. The attachment feature 403 of the first shaft 404 may comprise a enlarged portion 486, a threaded portion 488, and a stop 490. The enlarged portion 486, the threaded portion 488, and the stop 490 may all work in concert to secure the first shaft 404 to the housing 450. In one embodiment, the stop 490 may comprise a winged platform which may slide down longitudinal riders 494A and 494B within the threading of the threaded bore 452 as the threaded portion 488 engages the threaded bore 452 without engaging the threaded portion 488. The threaded portion 488 may be fully engaged when the winged platform of the stop 490 engages flanges 496A and 496B on an inner surface of the threaded bore 452. The stop 490 may prevent the first shaft 404 from threading too far into the threaded portion 488 and may assist in aligning the gear 454 to the rack 427 of the rack and pinion mechanism 436. The enlarged portion 486 may also be rotatably coupled to the threaded portion 488, such that the operator may turn the enlarged portion to drive the attachment feature into the housing 450.

[00149] Referring to Fig. 5C, when the first curved elongated member 426 is assembled to the second curved elongated member 438, the gear 454 of the rack and pinion mechanism 436 may project from the window 458 of the housing 450 to engage the rack feature 427 of the first curved elongated member 426 to move the first curved elongated member 426 along the track feature 444 of the second curved elongated member 438. In certain embodiments, the second curved elongated member 438 (or alternately the first curved elongated member 426) may have a stop, such as the pin 461, at one end portion which may insert into a bore hole 460 on the second end portion 424 of the first body alignment member 406. The stop may limit travel of the implant inserter 400. [00150] The second shaft 456 may further comprise a generally cylindrical shape dimensioned to be at least partially received by the first shaft 404 and in the first bore 480 and the second bore 484 of the handle 402, and the second cylindrical portion 468 of the turning knob 464, as previously described. The gear 454 of the rack and pinion mechanism 436 may be attached at to a distal end portion of the second shaft 456. The gear 454 may be coupled to the second shaft 456 so that an axial rotation of the second shaft 456 results in rotation of the gear 454 and at least a partial transfer of the torque applied to the turning knob 464 which may engage the rack 427 of the rack and pinion mechanism 436 on the first elongated curved member 426. The gear 454 may be rotated in either a clockwise or counterclockwise manner to translate the first curved elongated member and second curved elongated member either closer or farther apart, which may cause at least a portion of the spinal implant 30 (not shown) coupled to the implant inserter 400 to also translate.

The operator may receive the implant inserter 400 preassembled so that the handle 402 may be coupled to the second shaft 404 which has received the second shaft 456 coupled to the turning knob 464. The first body alignment member 406 and the second body alignment member 408 may be coupled to the pinion gear 454 of the second shaft 456 so that the rack and pinion mechanism 436 is engaged. The operator may fit and rotatably couple the first collet bushing assembly 500A (not shown) and the second collet bushing assembly 500B (not shown) to the first body alignment member 406 and second body alignment member 408, respectively. The operator may couple the distal end portion 504A of the first collet bushing assembly 500A and the distal end portion 504B of the second collet bushing assembly 500B by a torque transfer means to the spinal implant 30 such that a rotation of the first collet bushing assembly 500A or the second collet bushing assembly 500B may result in a tightening or loosening of at least one degree of freedom of the spinal implant relative to the spine 10 (not shown). Once the first collet bushing assembly 500A and the second collet bushing assembly 500B are locked to the spinal implant 30, the turning knob 464 of the inserter 400 may be rotated in order to contract or expand to align the bushings (not shown) of the spinal implant 30 (not shown) to the pedicle polyaxial heads (not shown).

Collet Bushing Assembly 500 (Fig. 6)

[00151] Referring now to Figure 6 A, the collet bushing assembly 500 may work in conjunction with other collet bushing assemblies and instruments to secure or at least partially secure one or more sides of a spinal implant 30 (not shown) in at least one degree of freedom. The collet bushing assembly may mate to a spinal implant (not shown) and receive one or more drivers (not shown) to assist in securing the spinal implant 30 (not shown). The collet bushing assembly 500 may also partially couple the implant inserter 400 (not shown) to the spinal implant 30 (not shown) to assist in aligning one or more spinal implants (not shown). The collet bushing assembly 500 and some or all of its parts may be manufactured from stainless steel or other metals.

[00152] Referring now to Fig. 6A, the collet bushing assembly 500 as shown in an exploded view may comprise a first outer member 510, a second outer member 540, an inner member 560 which extend generally along a longitudinal axis 598 and may be coupled by pins 580A and 580B. The first outer member 510 may be generally hollow and cylindrical in shape and have an inner surface defining at least a first bore 511 extending longitudinally, at least partially, through the first outer member 510. The first bore 511 may be dimensioned to receive at least a portion of the inner member 560 and be shaped as substantially concentric to a first portion 562 of the inner member 560. In the embodiment shown in Fig. 6A, the first bore 511 may be shaped as a hexagon dimensioned to receive concentrically a hexagon- shaped first portion 562 of the inner member 560 forming an adapter 506 (not shown configured) to transfer a torque from the inner member 560 to at least the outer member 510. It is to be understood that the first bore 511 and the received first portion 562 of the inner member 560 may form the adapter 506 (not shown) and be shaped as a hexagon, a square, a torx, or other sided polygon capable of transferring a torque. The adapter 506 (not shown) may receive one or more drivers which may rotate the collet bushing assembly 500 and transfer a torque to the spinal implant 30 (not shown).

[00153] The inner surface of the first outer member 510 may further define a second bore 512 extending longitudinally and lying along the longitudinal axis 598of the first outer member 510. The second bore 512 may be sized more narrowly and may have a generally cylindrical shape. The intersection of the first bore 511 and the second bore 512 may form an inner ridge 528 (not shown).

[00154] The first outer member 510 may also comprise a first interlocking feature 501 at an end portion corresponding to the second bore 512. The first interlocking feature 501 may comprise a first locking feature 505. The first interlocking feature 501 may interrelate with a second interlocking feature 503 of the second outer member 540 such that the first locking feature 505 and a second locking feature 507 of the second interlocking feature 503 form the locking feature 504 (not shown configured) of the collet bushing assembly 500. The locking feature 504 (not shown) of the collet bushing assembly 500 may couple and at least partially secure the spinal implant 30 (not shown).

[00155] The second outer member 540 may comprise a general cylindrical shape extending along the longitudinal axis 598 having an inner surface defining a bore 542 that is shaped as hexagon, a square, a torx, or other sided polygon capable of transferring a torque. The shape of the bore 542 may further be concentric to that of the first bore 511 of the first outer member 510. The outer diameter of the second outer member 540 may be generally smaller than the inner diameter of the first outer member 510 so that a portion 544 of the second outer member 540 may be received, at least partially, by the second bore 512 of the first outer member 510.

[00156] The inner member 560 may comprise the first portion 562 and a second portion 564. The first portion 562 may comprise an extended regular hexagonal shape dimensioned to fit at least partially into the bore 511 of the first outer member 510 and a lower outer edge 582 of the first portion 562 may sit on the ridge 528 (not shown) of the bore 511. The first portion 562 may be further dimensioned so that its shape is concentric to the shape of the bore 511 and is received by the bore 511 as to transfer torque at least between the inner member 560 and the first outer member 510. The second portion 564 may also comprise an extended regular hexagonal shape dimensioned to fit at least partially into the bore 542 of the second outer member 540. The second portion 564 may be further dimensioned to transfer a torque at least between the inner member 560 and the second outer member 540. The first and second portions 562 and 564 may be constructed as one unit and may each have an inner surface defining a bore 561 that runs through both the first portion 562 and second portion 564 and may be dimensioned to receive a shaft from various instruments such as the dual driver 800 (not shown), the collet driver 66 not shown), decoupler 900 (not shown). The bore 561 may further allow access to a torque -transfer element of the spinal implant 30 (not shown).

[00157] The inner member 560 may also comprise tracks 566 and 568 (not shown).

Each track 566, 568 (not shown) comprises an oblong recess in an outer surface of the second portion 564 with a sufficient width to receive the pins 580A and 580B allowing them to slide in each track 566, 568 (not shown). Each track 566, 568 (not shown) may have a length that extends longitudinally along one outer wall of the inner member 560. Each track 566, 568(not shown) may run along an outer wall of the second portion 564 of the inner member 560 that is opposite from the other. Tracks 566 and 568 (not shown) may also comprise a curved transverse portion which may turn the each track 566, 568 from running generally longitudinally to generally laterally and each generally extending laterally to form a general lateral section. The tracks 566 and 568 (not shown) may work and be oriented to allow a longitudinal sliding and a partial axial rotation of the inner member 560. [00158] The first portion 562 of the inner member 560 may further comprise along an inner surface of the bore 561 a plurality of bores 571, 572, 573, 574, 575, 576 which may each be dimensioned to receive a portion of the decoupler 900 (not shown) in order to allow the decoupler 900 (not shown) to remove the collet bushing assembly 500 from its connection with the spinal implant 30 (not shown). This interaction will be explained later in greater detail in reference to Figs. 8A, 8B, and 8C.

[00159] In the embodiment shown in Fig. 6B, the first interlocking feature 501 may comprise a plurality of extensions 514, 515, 516, and 517 of the outer member 510, each of the plurality of extensions 514, 515, 516, and 517 having a width which may define slots 518, 519, 520, and 521. End portions of each extension 514, 515, 516, 517 may comprise the first locking feature 505. The first locking feature 505 may be comprised of connection features on each of the extensions 514, 515, 516, and 517, respectively. In the embodiment shown in Fig. 6B, each connection feature of the first locking feature 505 may comprise a half tail shape of a dovetail joint dimensioned to mate with a connection feature comprising a half tail shape of a second locking feature 507 (not shown) of the second outer member 540. [00160] The first outer member 510 may comprise pin holes 522A and 522B, which may be located generally diametrically opposite from each other and along the same transverse plane along the outer surface of the first outer member 510. Pin holes 522A and 522B may be generally circular in shape and pass through the surface of the first outer member 510 and into the bore 512. Pin holes 522A and 522B may be dimensioned to receive pins 580A and 580B, as shown in Fig. 6A. The outer surface may further comprise at an end corresponding to the first bore hole 511, a ridge 508 which may rest on a corresponding rim of the implant inserter assembly 400 (not shown).

[00161] Now referring to Fig. 6C, there is shown a perspective view of the second outer member 540. The second outer member 540 may comprise a second interlocking feature 503 which may comprise enlarged portions 546, 547, 548, and 549 which may extend radially from an outer surface of the second outer member 540 and extend longitudinally from one end portion of the second outer member 540 generally towards the center of the second outer member 540. The enlarged portions 546, 547, 548, and 549 may be dimensioned to fit at least partially in slots 518, 519, 520, and 521 of the first outer member 510, as shown in Fig. 6B. The enlarged portions 546, 547, 548, and 549 may further define channels 550, 551, 552, and 553 between the enlarged portions 546, 547, 548, and 549. The channels 550, 551, 552, and 553 may be dimensioned to receive at least partially the extensions 514, 515, 516, and 517, respectively, of the first outer member 510. The locking feature 507 may comprise a connection feature on one end of each enlarged portion 546, 547, 548, 549. Each connection feature may comprise a half of a tail shape of dovetail joint dimensioned to mate with the first locking feature 505 of the first outer member 510, as shown in 6B.

[00162] The second outer member 540 of the collet bushing assembly 500 also may comprise pin slots 554A, 554B which may be located on the portion 544 of the second outer member 540. Each of the pin slots 554A, 554B generally forms a racetrack shape — two semicircles extended from each other by straight lines. Pin slot 554A may be generally located opposite from pin slot 554B on the same rotational plane of the second outer member 540 and may be dimensioned to receive pins 580A and 580B, respectively. The pins 580A and 580B may be dimensioned to slide laterally within the pin slots 554A and 554B and may allow the second outer member 540 to rotate relative to the first outer member 510. [00163] Referring now to Fig. 6D, the first outer member 510 may receive the second outer member 540 such that the extensions 514, 515, 516, and 517 translate between the enlarged portions 546, 547, 548, and 549. A partial rotation of the second outer 540 member may allow the connection features of the second outer member 540 to mate with the connection features of the first outer member 510 to form a set of complete tail shapes to connect with one or more features (not shown) on the spinal implant 30 (not shown). In the embodiment shown in Fig. 6D, the second outer member 540 has been rotated relative to the first outer member 510 such that the connection feature of each enlarged portion 546, 547, 548, 549 has rotated to form a complete tail shape of a dovetail joint with the connection feature of each extension 514, 515, 516, 517. The enlarged portions 546, 547, 548, and 549 and the extensions 514, 515, 516, and 517 may form a substantially equal outer diameter so that the first outer member 510 and the second outer member 540 form a substantially smooth and uniform cylindrical shape which may be received by the implant inserter assembly 400 (not shown).

[00164] Referring now to Fig. 6E, a cross sectional view of the collet bushing assembly 500 is shown. The pins 580A and 580B may couple the first outer member 510 by passing through the pin holes 522A and 522B of the first outer member 510 into the pin slots 554A and 554B of the second outer member 540 and into the tracks 566 and 568 of the inner member 560. The pins 580A and 580B may be permanently attached to the first outer member 510 by known methods such as press fitting or welding.

[00165] As a result, the inner member 560 may translate along the tracks 566 and 568 longitudinally relative to the first outer member 510 and the second outer member 560. The tracks 566 and 568 and the pin slots 554A and 554B of the second outer member 540 may allow for a partial rotation of the inner member 560 and the second outer member 540 relative to the first outer member 510.

[00166] Referring now to Figs. 6F through 6J, Fig. F illustrates a top view of the collet bushing assembly 500 where the inner member 560 and the first outer member 510 may be misaligned. Fig. G shows a side view corresponding to Fig. F. Fig. H F illustrates a top view of the collet bushing assembly 500 where the inner member 560 and the first outer member 510 may be aligned which may allow the inner member 560 to slide into at least the first outer member 510. Fig. 61 shows a side view corresponding to Fig. 6H. Fig. 6J is a side view showing that the inner member 560 has been inserted into at least the first outer member 510.

[00167] Referring now to Fig. 6F, the operator may use the collet bushing assembly

500 to connect to the bushing 32 of the spinal implant 30. The operator may receive the collet busing assembly 500 preassembled so that the inner member 560, first outer member 510 and second outer member 540 are coupled by the pins 580A and 580B (not shown). As shown in Fig. 6F and 6G, the operator may place the collet bushing assembly 500 in an initial configuration where the inner member 560 is pulled out at least in part from the first outer member 510. The hex shapes of the bore 511 of the first outer member 510 and the inner member 560 may be misaligned, such that the inner member may be prevented from sliding into the first outer member and the collet bushing assembly may be prevented from coupling to one or more features 34 and 36 of the bushing 32 of the spinal implant 30. The locking feature 507 of the second outer member 540 may be in an unmated position where the tails of the connection features are open to receive the one or more features 34 and 36 from bushing 32 of the spinal implant 30.

[00168] As shown in Fig. 6H and 61, the operator may place the collet bushing assembly 500 in a locked configuration by rotating the inner member 560 at least partially in order to align the hex shapes of the bore 511 of the first outer member 510 and the inner member 560. The operator may use an instrument (not shown) to rotate the inner member 560 or the inner member 560 may be manipulated by hand. The rotation of the inner member 560 may also rotate the second outer member 540 along the pin slots 554A (not shown) and 554B (not shown) which may mate the first locking feature 505 of the first outer member 510 with the second locking feature 507 of the second outer member 540 to form the locking feature 504. As shown in Fig. 61, the operator may close the tail shapes of the locking feature 504 so that the tail shapes grasp the one or more features 34 and 36 of the bushing 32 of the spinal implant 30. As shown in Fig. 6J, with the hexes of the inner member 560 and outer member 510 aligned, the inner member 560 may be pushed into the first outer member 510 and second outer member 540 so that the hexagon shape of the bore 511 of the first outer member 510 and the bore 542 (not shown) of the second outer member 540 align with the hexagon shape of the first portion 562 and second portion 564 (not shown) of the inner member 560, respectively. As shown in Fig. 6J, the inner member 560 may slide into at least the first outer member 510 and may engage the second outer member 540 in order to transfer a torque to the bushing 32 of the spinal implant 30. The operator may use a driver (not shown) to rotate inner member bore 561 and transfer a torque to the locking feature 504 of the collet bushing assembly 500 and to the spinal implant 30.

Left-Right Aligner 600 (Fig. 7)

[00169] Now turning to Fig. 7A a perspective view of the left-right alignment device

700 as shown which may be used to align a pair spinal implants 30A and 30B (not shown) implanted on opposite sides of the spine 10 (not shown). In certain embodiments the left- right alignment device 700 may have first elongated member 710 slidingly coupled to a second elongated member 720. A first end portion 712 of the first elongated member 710 may comprise a first hinged member 730 having a first bore 732. The first bore 732 may be dimensioned to receive a shaft of a first implant inserter device 400A (not shown). A first end portion 722 of the second elongated member 720 may comprise a second hinged member 740 having a second bore 742. The second bore 742 may be dimensioned to receive the shaft of a second implant inserter 400B (not shown). A locking member 750 with a locking nut 752 may constrain the position of the first elongated member 710 relative to the second elongated member 720. The whole device and its components may be composed of stainless steel, other metals, high strength polymers such as polyethersulfone and polyphenylsulfone, or any combination thereof.

[00170] In certain embodiments, the first elongated member 710 and the second elongated member 720 may each comprise a curved arc such that each trace at least a portion of a substantially common circumference. A surface of the first elongated member 710 and a surface of the second elongated member 720 may have a configuration such as a dovetail or tongue and groove which may allow a controlled sliding motion. In the embodiment shown in Fig. 7A, tongue portion 714 of the first elongated member 710 slidingly inserts into groove portion 724 (not shown) of the second elongated member 720. In some configurations, a surface of the first elongated member 710 and a surface of the second elongated member 720 may comprise demarcations 760 and 762 , respectively, such as lines showing relative distances from implant inserters 400A and 400B (not shown), respectively. These demarcations may be used to correlate the center of the common rotation axis 50 (not shown) to the position of the locking member 750 along the arcs of the first and second elongated members 710 and 720.

[00171] In the embodiment shown in Fig. 7B, the first hinged member 730 may be separately coupled by screws 713A and 713B or other fasteners to the first end portion 712 of the first elongated member 710. A first hinge pin 738 A may at least partially couple a first hinge plate 734 and a first closure member 736 of the first hinged member 730 so that the first closure member 736 may open to allow the first bore 732 to receive the shaft of the implant inserter instrument 400A, as shown in Figs. IA and IB. The first hinge plate 734 of the first hinged member 730 may have a first locking feature 764 comprising a slot which may communicate with a second locking feature 766 comprising a tab of the first closure member 736. The first locking feature 764 and second locking feature 766 may secure the first hinged member 730 around the shaft of the implant inserter instrument 400A (not shown).

[00172] The second hinged member 740 may be separately coupled by screws 723 A and 723B or other fasteners to the second end portion 722 of the second elongated member 720. A second hinge pin 738B may at least partially couple a second hinge plate 744 and a second closure member 746 of the second hinged member 740 so that the second closure member 746 may open to allow the second bore 742 to receive the shaft of the implant inserter instrument 400A, as shown in Figs. IA and IB. The second hinge plate 744 of the second hinged member 740 may have a third locking feature 768 comprising a slot which may communicate with a fourth locking feature 770 comprising a tab of the closure member 746. The third locking feature 768 and the fourth locking feature 770 may secure the second hinged member 740 around the shaft of the implant inserter 400B (not shown). [00173] The tongue portion 714 of the first elongated member 710 may comprise a protruding ridge along one side of the arc of the first elongated member 710. The groove portion 716 of the second elongated member 720 may comprise a slot along one side of the arc of the second elongated member 720 dimensioned to slidingly receive the tongue portion 714 so that the first elongated member 710 and second elongated member 720 fit together closely and slide along a common circumference. [00174] The locking member 750 may comprise a clamp configuration with a transverse bore 751 dimensioned to receive the locking nut 752. In some embodiments, the locking member 750 may fit the first elongated member 710 and the second elongated member 720 together as the first elongated member 710 slidingly engages the second elongated member 720. The locking member may lock the first elongated member 710 and the second elongated member 720 rigidly and prevent sliding between the first elongated member 710 and the second elongated member 720. The locking nut 752 may fit into the bore 751 in the locking member 750 and lock the relative position of the first elongated member 710 to the second elongated member 720 by compressing the locking member 750, the first elongated member 710 and the second elongated member 720 together. [00175] A target 754 may couple to a surface of the locking member 750 and may indicate the area correlating to the common center of rotation 50 (not shown) by providing a visual means of alignment and reducing the need for fluoroscopic imaging. The target 754 may be positioned so that when the first hinge member 730 and second hinge member 740 are properly positioned and locked to the shaft of the first and second alignment instrument 400A and 400B (not shown), respectively, the target 754 may assist in the alignment of the implants 30A and 30B (not shown) to the common center of rotation 50 (not shown). The target 754 may be comprised of a metal or other radio-opaque material which may distinctly appear during a fluoroscopic observation of the alignment instrument 700. The target 754 may be inlaid by press fitting or other commonly used method to fit the target 754 to the surface of the locking member 750.

[00176] The first elongated member 710 and the second elongated member 720 may have an arc or radius or other dimension which may correlate to the common center of rotation 50 (not shown). In other embodiments, the first elongated member 710 and the second elongated member 720 have an arc or radius or other dimension which may correlate to an arc about which the spinal implants 30A and 30B (not shown) may move. [00177] The operator may receive the left-right aligner 700 preconfigured so that the first hinge member 730 and the second hinge member 740 are coupled to the first elongated member 710 and second elongated member 720, respectively. The operator may lock the first hinge member 730 and second hinge member 740 of the first elongated member 710 and second elongated member 720 to the shafts of the implant inserters 400A and 400B (not shown). The operator may position the tongue portion 714 of the first hinge member 710 into the groove portion 724 of the second hinge member 720 adjusting the position of the shafts of the implant inserters 400A and 400B (not shown) until the first hinge member 730 and second hinge member 740 snap together. The operator may clamp the first and second elongated members 710 and 720 together by placing the locking member 750 over the first and second elongated members 710 and 720 and turning the locking nut 752 in the transverse bore 751. The operator may then position the target 754 by moving the left-right aligner 700 in order to properly align the spinal implants 30A and 30B (not shown) with a center of rotation. The operator may use fluoroscopy to assist the operator with placing the target 754.

Decoupler 900 (Fig. 8)

[00178] Referring now to Fig. 8A there is presented an exploded view of one embodiment of a decoupler 900 which may decouple the collet bushing assembly 500 (not shown) from the bushing 32 of one side of the spinal implant 30. The decoupler 900 may comprise a first shaft 902, a second shaft 904, a shaft head 906, a handle 908, a spring member 910, and a push cap 912, extending generally along a longitudinal axis 998. The entire assembly of the decoupler 900 may be manufactured from stainless steel or other metal.

[00179] The first shaft 902 may comprise a solid cylindrical member extending longitudinally and dimensioned to be received at least in part by the second shaft 904, the shaft head 906, the handle 908, the spring member 910, and the push cap 912. The first shaft

902 may have a first end portion 914 comprising a pin hole 920 which may extend laterally through the first shaft 902 and be dimensioned to receive a pin 922. The first shaft 902 may have second end portion 918 which may comprise an enlarged portion 916.

[00180] The second shaft 904 may comprise a tubular member extending along the longitudinal axis 998 and having a bore 924. The bore 924 may be dimensioned to receive, at least in part, the first shaft 902. The second shaft 904 may be dimensioned to be received, at least in part, by the shaft head 906 and by the handle 908. The second shaft 904 may have a first end portion 926 which may comprise a first attachment portion 928. The second shaft 904 may have a second end portion 930 which may comprise a second attachment portion 932.

[00181] The shaft head 906 may comprise a tubular member 946 extending along the longitudinal axis 998 and having a bore 934 dimensioned to receive, at least in part, the second attachment portion 932 of the second end portion 930 of the second shaft 904 and the second end portion 918 of the first shaft 902 including the enlarged portion 916. The shaft head 906 may further comprise a first extension 942 and a second extension 944 which may each comprise a cantilever extending longitudinally from a rim of the tubular member 946. In at least one embodiment, the first extension 942 and the second extension 944 may be positioned along the rim of the tubular member 946 so that the first extension 942 and the second extension 944 extend substantially parallel and may be dimensioned to connect to the collet bushing assembly 500 (not shown). A first end portion of the first extension 942 may comprise a first catch 938, and a first end portion of the second extension 944 may comprise a second catch 940. Each catch 938, 940 may comprise a flange dimensioned to insert into a bore hole (not shown) in the collet bushing assembly 500 (not shown). The first extension 942 and the second extension 944 may be biased inward toward each other in an undeflected position. It is to be understood that there may be more than two extensions and more than two bore holes which engage more than two bore holes on the collet bushing assembly 500 (not shown).

[00182] As shown in Fig. 8A, the handle 908 may comprise a gripping member comprising an inner surface defining a first bore 950, a second bore 951 and a rim 952. The first bore 950 may extend longitudinally at least partially through the handle 908 and have a rim 952 proximally near a first end portion 948 of the handle 908. The first bore 950 may be dimensioned to receive the spring member 910, at least a portion of the first shaft 902, and at least a portion of the push cap 912. The second bore 951 may extend longitudinally at least partially through the handle 908 and meet the first bore 950 on the inner surface of the handle 908 at the rim 952. The second bore 951 may be dimensioned to at least partially receive the first attachment portion 928 of the second shaft 904 and the first shaft 902. The rim 952 may comprise a flat surface which may bear a compression load from the spring member 910. The spring member 910 may comprise a standard compression spring having a generally helical shape dimensioned to fit in the bore 950 and transfer a compression load of the spring member 910 to the rim 952 and to a bottom surface 954 of the push cap 912. The spring member 910 may have a bore dimensioned to receive at least a portion of the first shaft 902. [00183] The push cap 912 may comprise a generally solid cylindrical member extending along the longitudinal axis 998 and having a first bore 956 (not shown) extending at least partly but not fully into a bottom surface 954 of the push cap 912. The first bore 956 (not shown) may be dimensioned to at least partially receive the first shaft 902. The push cap 912 may further comprise a second bore hole 957 which may extend laterally and intersect the first bore hole 956. The second bore hole may be dimensioned to receive the pin 922 so that the pin 922 passes laterally through the push cap 912.

[00184] Referring now to Fig. 8A, the decoupler 900 may be assembled prior to use in the operating room. The decoupler 900 may be constructed by fitting the second attachment portion 932 of the second end portion 930 of the second shaft 904 into the bore hole 934 of the shaft head 906. It is to be understood that the second attachment portion 932 may couple to the bore hole 934 by many standard methods, such as a threaded configuration or a gripping surface. The first shaft 902 may be inserted at least partially into the shaft head 906 and the bore 924 of the second shaft 904 so that the enlarged portion 916 is generally oriented toward the shaft head 906 and between the first extension 942 and the second extension 944. The first shaft 902 may slide freely with the second shaft 904 and the shaft head 906.

[00185] Referring now to Fig. 8B, the first end portion 914 of the first shaft 902 may be inserted at least partially into the first bore hole 951 of the handle 908 so that the first end portion 914 of the first shaft 902 extends from the second bore hole 950 of the handle 908. The first end portion 948 may receive in the first bore hole 950 the spring member 910, at least partially, so that one end of the spring member 910 sits on the rim 952. The first shaft 902 may pass through the helical shape of the spring member 910 and may be received by the first bore 956 of the push cap 912 so that the spring member 910 may be compressed between a bottom surface 954 of the push cap 912 and the rim 952.

[00186] The pin 922 may be received by a portion the second bore hole 957 of the push cap 912 and be received by the bore 920 of the first shaft 902 and be received by an opposing portion of the second bore hole 957 of the push cap 912. The pin 922 may be permanently affixed to the second bore hole 957 of the push cap 912 by standard methods, such as press fitting. The pin 922 may couple the first shaft 902 to the push cap 912 so that depressing the push cap 912 may compress the spring member 910 and may provide for a longitudinal movement of the first shaft 902 through the second shaft 904 and shaft head 906. [00187] As shown in Fig. 8B, the operator may use the decoupler 900 to pull and release the collet bushing assembly 500 from the spinal implant 30 (not shown). The operator may place the decoupler 900 into an engagement/release configuration by depressing the push cap 912 which may deflect the spring member 910 and extend the enlarged portion 916 away from the shaft head 906. The operator may insert the first extension 942 and the second extension 944 into the collet bushing assembly 500 which because of the inward bias of the first extension 942 and the second extension 944 may enter the collet bushing assembly 500 without making contact with any surface of the collet bushing assembly 500.

[00188] The decoupler 900 may have a pulling out configuration as shown in Fig. 8C.

The operator may release the push cap 912 which may retract the enlarged portion 916. The enlarged portion 916 may comprise a lead-in surface 958 which may make contact with the first extension 942 and the second extension 944. The lead- surface 914 may act as a wedge to introduce the enlarged portion 916 into a volume between the first extension 942 and the second extension 944. When the push cap is released, the spring member 910 may expand which may transfer the compression load of the spring member 910 to the enlarged portion 916 and further pull the enlarged portion 916 into the volume. The enlarged portion 916 may deflect the first extension 942 and the second extension 944 and push the first catch 938 and second catch 940 into a first bore hole 572 and second bore hole 575 of the collet bushing assembly 500. The catches 938 and 940 may give the dual driver 900 contact with which to apply a removing force on the collet bushing assembly 500. The enlarged portion 916 may rest between the extensions 942 and 944 so that the enlarged portion 916 applies a holding force to the catches 938 and 940 in the bore holes 572 and 575. The operator may pull up on the handle 908 to disengage the collet bushing assembly 500 from the bushing 32 (not shown) of the spinal implant 30 (not shown). [00189] After the collet bushing assembly 500 has been disengaged from the spinal implant 30 (not shown), the operator may again place the decoupler 900 into the engagement/release configuration, as shown in Fig. 8B, by depressing the push cap 912 on the handle 908. The enlarged portion 916 of the first shaft 902 may advance through the shaft head 906 into the collet bushing assembly 500. The extensions 942 and 944 may return to the inward bias and disengage from the catches 938 and 940, respectively. The operator may pull the decoupler 900 from the collet bushing assembly 500, and release the decoupler 900.

Method of Spinal Implant Alignment (Fig. 9-15)

[00190] A method of inserting the spinal implant 30 will be described with reference to Figures 9A and 9B through 10. Figs. 9A and 9B are two perspective views of a bone anchor (such as a pedicle screw, bone screw, plate, hook or cage) connected to the pedicle screw driver 200. In the embodiments, the bone anchor is referred to as a pedicle screw 2OA. Figure 1OA, 1OB, and 1OC are perspective views of the spine 10 collectively showing embodiments of a pair of polyhead holders 300A and 300B with extension guide assemblies HOA and HOB and the implant inserter 400A in use with the implant insertion and alignment assembly 100.

Patient Positioning

[00191] Referring now to Fig. 9A and 9B, prior to placement of the implant 30A, the patient may be positioned and prepped using preferred surgical techniques. A vertebral level may be chosen comprising the second vertebra 14 and the first vertebra 12, as shown in Fig. 9. The second vertebra 14 and first vertebra 12 each define a side with a pedicle site and an opposite side with a pedicle site, respectively. In addition, use of C-arm fluoroscopy may be utilized for pedicle site identification and targeting. The pedicle site may be targeted using standard interoperative techniques under fluoroscopy. A device such as a pedicle targeting device ("PTD") (not shown) may be advanced to a desired depth within the vertebral body without breaching the pedicle during placement. A guide wire 60 may be placed through the PTD (not shown) and advanced into the vertebral body and may define a guide wire trajectory which may assist the operator with aligning an angle of a threaded portion 21 A of the pedicle screw 2OA to ensure proper advancement of the pedicle screw 2OA into the bone. The guide wire 60 may comprise a tip such as a blunt or trocar tip, depending on the preference of the operator. The guide wire 60 may be positioned approximately two-thirds of the way through the vertebral body. Throughout the procedure, the guide wire 60 position may be monitored to ensure that the tip is not advanced. The PTD (not shown) may be removed while maintaining control of the guide wire to prevent pullout. A more detailed description of these methods and steps is provided in U.S. Patent Application 10/989,715, entitled "An Extension For Use With Stabilization Systems For Internal Structures," filed on November 16, 2004, which is hereby incorporated by reference for all purposes. [00192] The pedicle may be prepared to receive the pedicle screw 2OA through use of a combination of dilators (not shown), a pedicle preparation device (not shown), and a tap (not shown). The dilators may assist in separating tissue and muscle from the pedicle site. The pedicle preparation device (not shown) may create a countersink on a dorsal surface of the pedicle that may be sized to match the screw tip. The tap (not shown) may create a tap hole (not shown) for the pedicle screw 2OA. The depth of the tap hole may be estimated using known surgical techniques. The tap hole may at least extend beyond the posterior wall of the pedicle. Once the pedicle site is prepared, the tap may be removed and the pedicle screw length and diameter selected using standard practice and fluoroscopic imaging. A more detailed description of these methods and steps is provided in U.S. Patent Application 10/989,715, entitled "An Extension For Use With Stabilization Systems For Internal Structures," filed on November 16, 2004, which is hereby incorporated by reference for all purposes.

Screw Assembly and Insertion

[00193] Referring now to Fig. 9A, prior to pedicle screw placement, the pedicle screw

2OA may be coupled to the polyaxial head 22A and the joined assembly may be connected to the polyhead holder assembly 300A. Referring now to Fig. 9B, the polyhead holder 300A may be locked onto the polyaxial head 22A by aligning the first head groove 24 and the second head groove 26 so that the first head groove 24 is proximal to the body 302 of the polyhead holder 300. [00194] Referring now to Fig. 3E, the first arm 340 and the second arm 390 may be rotated as to firmly grasp the polyaxial head 22 by using a small polyhead driver 40 (as shown in Fig. 3D). The small polyhead driver 40 may coupled to the adapter 399 of the polyhead holder 300. The small polyhead driver 40 may apply a torque to the adapter 399 as to rotate the arms by means described above. The locking features 350 and 391 of the first arm 340 and the second arm 390 of the polyhead holder 300 may mate with the locking features (not shown) of the polyaxial head 22. These steps may be applied to the polyhead holders 300A, 300B, 300C, and 300D shown in Fig. IA to attach to the respective polyaxial heads 22A, 22B, 22C, and 22D.

[00195] Referring now to Fig. 9A and 9B, a first pedicle site may be chosen by the operator according to known surgical techniques. The pedicle site corresponding to a side of the first vertebra 12 has been chosen. By means described above in Fig. 2E and as shown in Fig. 9A, the screwdriver assembly 200 may be mated to the joined assembly of the polyaxial head 22A and the pedicle screw 2OA, which may already be attached to the polyhead holder 300A. In addition, a handle 202 may be attached to an end of the inner shaft 201 to assist in the application of torque to the pedicle screw 2OA.

[00196] Referring now to Fig. 9B, the pedicle screw 2OA may receive a portion of the guide wire 60 through a bore 23 A in a threaded portion 21 A of the pedicle screw 2OA. The pedicle screw 2OA may be slid down the guide wire 60 to the bone surface until the screw tip portion 25 A is fully seated in the tap hole. The location of the pedicle screw 2OA in relation to the pedicle site and tap hole may be confirmed with fluoroscopy.

[00197] The screwdriver assembly 200 may be held in place as the guide wire 60 is removed. The angle of the threaded portion 21 A of the pedicle screw 2OA may be aligned to the previous trajectory of the guide wire 60. The screw tip portion 25A may comprise a conical shape which may follow the tapped pedicle path. With the screw tip portion 25A in place and the angle of the threaded portion 21 A aligned, a torque may be applied to the ratchet handle 202 (as shown in Fig. 9A) as to advance the pedicle screw 2OA into the pedicle site. The operator may use the pedicle screw driver 200 to advance the pedicle screw 2OA to an appropriate depth according to known surgical techniques and under the guidance of fluoroscopy. The ratchet handle 202 and screwdriver assembly 200 may be removed. The polyaxial head 22A may be rechecked to ensure polyaxial movement.

[00198] Tissue and muscle may be swept away from the entry point of the pedicle.

Prior to removal of the screwdriver 200, a tissue separator (not shown), comprising a sharp and a dull side at an end and a handle at an opposing end, may be inserted down a side of the screwdriver 200 so that the tissue separator may pass through without cutting additional tissue. The sharp or dull side (not shown) may then be used to sweep tissue from the second pedicle 14 to the first pedicle 12 or vice versa.

[00199] The above described method may be utilized to insert additional pedicle screws 2OB, 2OC, and 2OD (as shown in Fig. IB). Generally, for the placement of a spinal implant 30, at least two pedicle screws 2OA, 2OB, 2OC, and 2OD and respective polyaxial heads 22A, 22B, 22C, and 22D may need to be inserted, one on the first vertebra 12 and one on the second vertebra 14. By example, Fig. IB shows the pedicle screws 2OA, 2OB, 2OC, and 2OD have been inserted by using the described method. Additional pedicle screws beyond the four shown may be inserted into adjacent vertebral levels depending on the requirements of the medical procedure.

Implant Size Selection

[00200] Prior to insertion, the operator may select the appropriate size spinal implant

30 by using a pedicle to pedicle measurement device such as the rod-length indicator as described in A more detailed description of these methods and steps is provided in U.S. Patent Application 11/676,101, entitled "Rod Length Measuring Instrument," filed on February 16, 2007, which is hereby incorporated by reference for all purposes. The operator may utilize other known surgical methods to determine the correct size implant. [00201] Once the correct size spinal implant 30A is determined, the implant inserter

400A may be coupled to the spinal implant 30A, as described in Figures 5A and 5B. The collet bushing drivers 500A and 500B are inserted into the first body alignment member 406A and the second body alignment member 408A, respectively. According to methods described previously in Figure 6E-6I of this specification, the operator may couple the first collet bushing driver 500A and the second collet bushing driver 500B to a first and second bushing (not shown) of the spinal implant 3OA. In certain embodiments, the correct position of the first body alignment member 406A and second body alignment member 408A may be locked. The position of a first end relative to a second end of the spinal implant 3OA may also be locked.

Implant Placement

[00202] Referring now to Figs. 1OA, 1OB, and 1OC, there is shown perspective views of the first polyaxial head 22A and second polyaxial head 22B installed in the first vertebra 12 and the second vertebra 14, respectively, on the chosen side of the spinous process of the spine 10. The operator may install the first polyhead holder 300A and second polyhead holder 300B to the first polyaxial head 22A and second polyaxial head 22B, respectively. In Fig. 1OA, the operator may install a first extension guide assembly HOA and a second extension guide assembly HOB to the first polyhead holder 300A and second polyhead holder 300B. The first extension guide assembly HOB may comprise an elongated body 112B having a head portion 114B and an elongated shank 116B. At a distal end of the elongated shank 116B, a first bore hole 118B (not shown) and a second bore hole 120B (not shown) may be dimensioned to receive a first connection post 122B and a second connection post 124B in order to couple the first extension guide assembly 11OB to the second polyhead holder 300B.

[00203] As shown in Fig. IA and IB, the first extension guide assembly 11OA may be identical to the first extension guide assembly 11 OA, the third extension guide assembly HOC, and the fourth extension guide assembly HOD. The same steps may be used to connect one or more extension guide assemblies 11 OA, HOC, and HOD to each respective polyhead holder 300A, 300C, and 300D.

[00204] Referring now to Fig. 1OA, the head portion 114B of the first extension guide assembly HOB may comprise a generally cylindrical structure with a bore 126B extending longitudinally through the center axis of the head portion 114B. The elongated shank 116B may extend from the head portion 114B towards a distal end of the elongated body 112B. The elongated shank 116B may have a concave front surface for receiving and guiding one more spinal implants (not shown). [00205] As shown in Fig. 1OA, the operator may couple the first extension guide assembly 11OB to the first polyhead holder 300B which may at least partially receive the first connection post 122B and the second connection post 124 A in the first bore hole 312A and the second bore hole 314A of the of the polyhead holder 300A.

[00206] Referring now to Fig. 1OB, once the extension guide assemblies HOA and

HOB are installed and the implant inserter 400A is coupled to the spinal implant 30A, the operator may then slide the implant inserter 400A with the attached spinal implant 30A down the pair of extension guide assemblies 11OA and HOB, as shown in Figure 1OB. In certain embodiments, the implant inserter assembly 400A may help guide the spinal implant 30A along the concave surface of the elongated shank 116A of the first extension guide assembly 11 OA until the spinal implant 30A is adjacent to the polyaxial head 22A (not shown) of the pedicle screw 2OA. Alternatively, the implant inserter assembly 400A may help guide the spinal implant 30A along the concave surface of the elongated shank 116B of the second extension guide assembly HOB until the spinal implant 30A is adjacent to the polyaxial head 22 A (not shown) of the pedicle screw 2OA.

[00207] Once the spinal implant 30A is adjacent to the polyaxial head and pedicle screw 2OA (not shown), the operator may secure a first side of the spinal implant 30A to the first pedicle screw 2OA. A second non-secured side of the spinal implant 30A may then be secured to second pedicle screw 2OB.

[00208] Now referring to Fig. 1OC, the dual driver 800 may assist in at least partially securing the bearing posts of the spinal implant 30A to the polyaxial heads 22 A and 22B. The operator may insert the dual driver 800 into the collet bushing assembly 500B in the second configuration, as described previously, so that the dual driver 800 may engage the bearing post (not shown) and the bushing (not shown) of the spinal implant 30A. The dual driver 800 may pass through the head portion 114B of the second extension guide assembly HOB and may engage the bearing post torx (not shown) and the hex portion (not shown) of the collet bushing assembly HOB. The bearing post (not shown) of the spinal implant 30A may be engaged first followed by aligning the hex (not shown) of the dual driver 800 with the hex of the adapter 506A of the collet bushing assembly HOB. The bearing post (not shown) of the spinal implant 30A may be lightly tightened to the polyaxial head 22B. The polyaxial motion of the polyaxial head may be maintained by only rotating the dual driver 800 through 2 or 3 turns. The same steps may be applied to secure the non-secured side of the spinal implant 3OA corresponding to the polyaxial head 22 A by removing the dual driver 800 from the collet bushing assembly 500B and the second extension assembly HOB. This process for securing the spinal implant 30A may be repeated for the same vertebrae 12 and 14, but on the left side of the spinous process for the spinal implant 30B.

Repeat Procedure on Lateral Side

[00209] Referring now to Figs. 1OD and 1OE a top view of the first vertebra 12 is shown illustrating a theoretical center of rotation 52 and 54 from spinal implants 30A (not shown) and 30B (not shown), respectively. After the first spinal implant 30A is inserted, a second spinal implant 30B may be inserted into the same vertebrae, but a contra-lateral side of the spinous process. Once inserted, the respective center of rotations 52 and 54 may not be aligned in a left-right configuration, as shown in Fig. 10D. In certain embodiments as shown in Fig. 1OE, it may be desirable for the center of rotation 52 of the first spinal implant 30A to be aligned with the center of rotation 54 of the second spinal implant 30B (not shown) forming a common center of rotation 50. The operator may need to take several fluoroscopy images as the operator adjusts the spinal implant 30A to determine if the spinal implant 30 is properly aligned with the center of rotation 50. An overlay (not shown) may be placed over the fluoroscopy image screen to aid the operator in aligning the spinal implant 30A to the center of rotation 50. The common center of rotation 50 for both implants 30A and 30B may allow a more natural motion of the spine as the spinal implants 30A and 30B control and stabilize the movement along the common center of rotation 50.

Implant Alignment

[00210] Referring now to Figs. HA and HB, a first and second perspective view of the attachment of the left-right aligner 700 to the implant inserter 400A is shown. In certain embodiments, the left-right aligner 700 may be used in conjunction with one or more implant inserters 400A and 400B (not shown) to align two or more spinal implants 30A and 30B (not shown) and more specifically two or more centers of rotation 52 and 54 to a common center of rotation 50 (as shown previously in Figs 1OD and 10E). The left-right aligner 700 may temporarily couple the implant inserter 400A of the first spinal implant 3OA with the implant inserter 400B (not shown) of the second spinal implant 30B (not shown). [00211] The left-right aligner 700 may be coupled to the first implant inserter 400A by inserting the shaft 404 A of the first implant inserter 400A into the first hinged member 730 of the left-right aligner 700. Referring now to Fig. 1 IB, the first hinged member 730 may be locked to the shaft 404 A at a height correlated to the spinal implant 30A by snapping the locking feature of the first piece 734 of first hinged member 730 in into the locking feature of the second piece 736 of the first hinged member 730. Demarcated grooves 492A along the shaft 404 A may assist in positioning and locking the first hinged member 730 along and to the shaft 404A.

[00212] Referring now to Fig. 12A, the same steps may be repeated for locking the second hinged member 740 to the shaft 404B of the second implant inserter 400B. The demarcated grooves 492B of the second implant inserter 400B and the demarcated grooves 492 A of the first implant inserter 400A may be coordinated such that the first hinged member 730 and the second hinged member 740 are locked at substantially the same height. The operator may bring together the first elongated member 710 and the second elongated member 720 so as to be substantially parallel and so that one slides into the other. In some embodiments, the first elongated member 710 and the second elongated member 720 may snap together at a certain distance apart which may define a relative orientation between the first elongated member 710 and the second elongated member 720 where the first elongated member 710 and the second elongated member 720 may be locked. As shown in Fig. 12A, the operator may adjust the arcs of the first elongated member 710 and the second elongated member 720 by opening and closing the left-right aligner 700 until the motion feels smooth to the operator.

[00213] Referring now to Fig. 12B, once the arcs of first elongated member 710 and the second elongated member 720 have acquired the locking position, the operator place the locking member 750 in the center of an arc formed by the first elongated member 710 and the second elongated member 720. The operator may lock the left right aligner 700 in place by inserting and fastening the locking nut 752 into the locking member which may tighten the first elongated member 710 and the second elongated member 720 together. Final Tightening

[00214] As shown in Fig. 12B, once the left-right aligner 700 is locked in place, the left-right aligner 700 the operator may adjust and move the implant inserters 400A and 400B and thus the spinal implants 30A and 30B relative to one another which may align the two corresponding centers of rotation 52 and 54 to a common center of rotation 50, as shown in Fig. IB and 1OE. The operator may take fluoroscopy images to confirm the corresponding centers of rotation 52 and 54 (not shown) are aligned. The operator may also utilize the target 754 to help adjust the left-right aligner 700 and correctly align the spinal implants 30A and 30B to the center of rotation 50 (not shown).

[00215] Referring now to Fig. 13 A, the operator may tighten the spinal implants 30A and 30B to a certain torque level which may prevent any further movement of the polyaxial heads 22A and 22B (not shown) of the pedicle screws 2OA, 2OB, 2OC, and 2OD (not shown). The operator may use the dual driver 800 to tighten the bearing posts (not shown) of the spinal implants 30A and 30B. The dual driver 800, configured in the second configuration, may be inserted into the extension guide assembly HOD through the head portion 114D and along the elongated shank 116D so that the dual driver 800 engages the bearing post (not shown) of the pedicle screw 2OD (not shown). A counter-torque wrench 62 may be attached to the extension guide assembly HOD so as to hold the polyhead holder 300D in place throughout tightening. A torque-limiting T-handle 64 may be attached to the dual driver 800. While holding the counter-torque wrench 62, the operator may tighten the bearing post (not shown) of the spinal implant 30B until one or two audible clicks (indicating 75 in- lbs, for example) are achieved with the first torque limiting T-handle 64. In the second configuration, the dual driver 800 may engage the collet bushing assembly 500D of the spinal implant 30B throughout the tightening of the bearing post (not shown). The operator may remove the dual driver 800 along with the counter wrench 62 and the first torque limiting T-handle 64.

[00216] The operator may follow the same steps to tighten the bearing posts (not shown) of the spinal implants 30A and 30B corresponding to the other collet bushing assemblies 500B, 500A and 500C. The operator may tighten the bearing posts in a specific pattern such as the first vertebrae on one side and the second vertebrae on the other. In the embodiment shown in Fig. 12A, the extension guide assemblies HOA, HOB, HOC and HOD may be attached prior to tightening of all of the bearing posts (not shown). Alternatively, each extension guide assembly 11OA, HOB, HOC, HOD may be attached only when needed to secure a respective collet bushing assembly 11OA, HOB, HOC, HOD. [00217] Referring now to Figure 13B, following the tightening of the bearing posts

(not shown) of the spinal implants 3OA and 30B, the operator may tighten the bushings (not shown) of the spinal implants 30A and 30B using a collet driver 66. The collet driver 66 may be inserted into the extension guide assembly HOD through the head portion 114D and along the elongated shank 116D so that the collet driver 66 engages the collet bushing assembly 500D at the adapter 506D. The collet driver 66 may be comprised of a shaft with a first end portion further comprising a hex feature (not shown) which may be dimensioned to transfer a torque to the adapter 506D. A second end portion of the collet driver 66 may comprise an adapter (not shown) to receive a handle (not shown). In the embodiment shown, a second torque limiting T-handle 68 may be attached to the adapter (not shown) and the counter-torque wrench 62 may be attached to the extension guide assembly HOC so as to hold the polyhead holder 300D in place throughout tightening. While holding the counter- torque wrench 62, the operator may tighten the collet bushing assembly 500D until one or two audible clicks (indicating 110 in- lbs, for example) are achieved with the second torque limiting T-handle 68.

Instrument Removal

[00218] After the spinal implants 30A and 30B are fully secured, the operator may remove the left-right aligner 700 from the implant inserters 400A and 400B and the operator may remove the implant inserters 400A and 400B from the spinal implants 30A and 30B, respectively. By use of the polyhead holder driver 40 (not shown) as described in Figs. 3B, 3C, 3D, 3E, the operator may remove the polyhead holders 300A, 300B, 300C and 300D from the polyaxial heads 22A, 22B, 22C and 22D, respectively. Extension guide assemblies 11 OA, HOB, HOC, and HOD may be removed before or along with the polyhead holders 300A, 300B, 300C, and 300D. [00219] Referring now to Fig. 14 there is shown a perspective view of the decoupler

900 in use to remove the collet bushing assembly 300B. In certain embodiments, the decoupler 900 may be used to release each collet bushing assembly 500A, 500B, 500C, 500D from the respective connection with the implant 30A and 30B, as shown in 13B. The push cap 912 may be pressed to advance the enlarged portion 916 past the extensions 942 and 944. To release the collet bushing assembly 500B, the operator may push the shaft head 906 into the collet bushing assembly 500B, whereby the extensions 942 and 944 have an initial inward bias. The operator may release the push cap which may retract the enlarged portion 916 into the shaft head 906 so that the catches 938 and 940 (not shown) of the extensions 942 and 944, respectively, are firmly held by the enlarged portion 916 in the bore holes (not shown) of the collet bushing assembly 500B. The enlarged portion 916 may wedge between the extensions 942 and 944 to press the catches 938 and 940 (not shown) firmly into the bore holes (not shown) of the collet bushing assembly 500B. The decoupler 900 may then be pulled and the push cap 912 released which may disengage the collet bushing assembly 500B from the bearing (not shown) of the spinal implant 30A. The operator may again depress the push cap 912 to advance the enlarged portion 916 into the collet bushing assembly 500B and return the extensions 942 and 944 to their initial inward bias. The operator may repeat these same steps for the other collet bushing assemblies 500A, 500C, and 500D. Removing the collet bushing assemblies 500A, 500B, 500C, and 500D may allow the operator to remove the implant inserter assemblies 400A and 400B from the spinal implants 30A and 30B, respectively.

[00220] Referring now to Figure 15, there is shown one embodiment of the secured spinal implants 30A and 30B secured into the spine 10 at the vertebrae 12 and 14 on both sides of the spinous process, respectively. The spinal implants 30A and 30B may be aligned to the common center of rotation 50. Once all instruments have been removed, leaving the embodiment shown in Figure 15, the operator may close the surgical site repeat this process for an adjacent vertebral level.

[00221] Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the following claims.

Claims

1. A spinal implant insertion system comprising: a right implant inserting tool for inserting a right spinal implant, a left implant inserting tool for inserting a left spinal implant, wherein each of the right and left implant inserting tools include: a handle means, an implant coupling means, the implant coupling means having: a first end coupling means for coupling to one end of a spinal implant, a second end coupling means for coupling to the other end of the spinal implant, an angular distance adjusting means for adjusting an angle between the first end coupling means and the second end coupling means, the angular distance adjusting means including: a first curved longitudinal member, and a second curved longitudinal member slidingly coupled to the first curved member, wherein the angular adjusting means is coupled to the handle means, an aligner for aligning the right spinal implant and left spinal implant to a center of rotation region, the aligner having: a first means to detachably couple to the right implant inserting tool, a second means to detachably couple to the left implant inserting tool, a means for angularly aligning the right implant inserting tool and the left implant inserting tool such that the right implant and a left implant are aligned to the center of rotation region.

2. The system of claim 1, where the angular distance adjusting means of the right or left implant inserter further comprise: an adjustment means for adjusting the position of the first curved member relative to the second curved member, the adjustment means further comprising: a pinion means coupled to a distal end of an interior shaft coupled to the handle means and rotatably coupled to a rack gear means coupled to one of the first or second curved longitudinal members.

3. The system of claims 1 or 2, wherein the means for angularly aligning on the aligner further comprises: a first curved longitudinal member, a second curved longitudinal member slidingly coupled to the first curved member, and a locking means for locking the position of the first curved member relative to the second curved member, and a target means for visually confirming alignment of the right spinal implant and left spinal implant.

4. The system of claims 1 through 3, wherein the aligner includes a means showing relative distances from the implant inserters to determine the relative offset of the right spinal implant and left spinal implant.

5. The system of claims 1 through 4, further comprising a means to adjust for the radial implantation positions of the left spinal implant and right spinal implant relative to the center of rotation region.

6. The system of claims 1 through 5, wherein the handle means includes: vertical markings for positioning the aligner marked on the shaft, a longitudinal bore defined within an exterior shaft such that the interior shaft can rotate within the longitudinal bore to transmit torque from a turning knob positioned at the proximal end of the handle to the pinion means.

7. The system of claim 1 , wherein the first end coupling means or the second end coupling means each comprise a collet driver means detachably coupled to the respective end coupling means, wherein the collet driver means further includes: a proximal end having a driver engagement means for receiving a torque from a driver, a distal end having a collet coupling means for detachably coupling to a collet of a spinal implant and transmitting the torque to the collet of a spinal implant, and a passage means for allowing a passage of a second driver through the collet driver means.

8. The system of claim 7, further comprising: a first tubular coupler having a first plurality of projections adapted to couple to one side of a series of dovetail projections on the collet of a spinal implant, a second tubular coupler rotatably coupled to the first tubular coupler and having a second plurality of projections adapted to couple to the other side of the series of dovetail projections, and an interlinking means for rotating the first tubular coupler relative to the second tubular coupler between an unlocked position and a locked position, wherein in the unlocked position the first and second plurality of projections do not couple to both sides of the plurality of dovetail connections and in the locked position the first and second plurality of projections engage both sides of the plurality of dovetail projections.

9. The system of claim 7, further comprising a dual driver means, the dual driver means comprising: an internal shaft means including: an internal proximal portion having an internal torque receiving engagement means, an internal distal portion having an internal distal torque transmission means adapted to couple to a torque receiving means of a bearing post of a spinal implant, an outer casing means slidingly and rotatably coupled to the internal shaft means, the outer casing means including: an outer proximal portion having an outer torque receiving engagement means, and an outer distal end portion having an outer torque transmission means adapted to couple to the driver engagement means of the collet driver means.

10. The system of claim 1 , further comprising: a plurality of longitudinal guide means, wherein each longitudinal guide means has: a longitudinal guide portion for slidingly engaging a portion of one of the implant coupling means of the right or left inserting tools, and a polyaxial screw head holding means detachably coupled to the longitudinal guide means.

11. The system of claim 10, further comprising: a torque receiving means coupled to the polyaxial screw head holding means for receiving a torque from a driver, a first arm coupled to the polyaxial screw head holding means and having a first engagement means for engaging a polyaxial screw head, a second arm coupled to the polyaxial screw head holding means having a second engagement means for engaging the polyaxial screw head an arm adjustment means coupled to the torque receiving means such that when torque is received the adjustment means adjusts the position of the first arm and second arm to allow the engagement means to engage the polyaxial screw head, and an access port defined within the longitudinal guide means for providing access to the torque receiving means for the driver.

12. The system of claim 11 , wherein the arm adjustment means further comprises: a first pivot post, a second pivot post, a first cam surface coupled to the first arm, a second cam surface coupled to the second arm, an arm actuator means coupled to the torque receiving means such that as the torque receiving means is rotated, the arm actuator moves longitudinally to engaging the first and second cam surfaces causing the first and second arms to pivot about the first and second pivot posts, respectively.

13. The system of claim 1, further comprising a screw driver means comprising: an internal shaft means having a proximal portion and a distal portion, wherein the distal portion having a distal torque transmission means adapted to couple to a torque receiving means of a screw, an outer casing having a distal end portion wherein the distal end portion includes a screw shaft coupling means for coupling to a screw shaft while bypassing a polyaxial screw head coupled to the screw shaft, and an adjustment means for securing the torque transmission means to the torque receiving means of the screw.

14. The system of claim 13, wherein the screw shaft coupling means further comprising a C-clip means having a first end portion adapted for coupling to the outer casing and a second portion adapted for coupling to the shaft of the screw shaft.

15. The system of claims 1 through 14, further comprising a decoupler means, the decoupler means comprising: an elongated member having a proximal end portion and a distal end portion, an engagement means coupled to the distal end of the elongated member and adapted to releasably couple to an interior engagement surface of the collet driver means, wherein the engagement means moves from an unexpanded position to an expanded position, an actuator means coupled to the proximal end portion and to the engagement means such that the actuator means controls the movement of the engagement means from the unexpanded position to the expanded position.