SYSTEM AND METHOD FOR MINIMALLY INVASIVE POSTERIOR FIXATION
The present invention relates generally to systems and methods for aligning and implanting orthopedic fixation or stabilization implants within the body. In one embodiment, the system includes at least two bone anchors, at least one of which is provided with an angularly adjustable connector. In one aspect, the system also includes at least one linkage rod, for linking two or more bone anchors through their respective adjustable connectors. The bone anchors and the linkage rod may be locked into place to form a spinal fusion or fixation prosthesis. An alignment tool is provided, for guiding a guidewire through one or more connectors.
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This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 60/465,902 filed on Apr. 25, 2003, the disclosure of which is incorporated by reference in its entirety herein.
BACKGROUND OF THE INVENTION1. Field of the Invention
The present invention relates generally to medical devices and, more particularly, to systems for aligning and implanting orthopedic fixation or stabilization implants within the body. In one application, the present invention relates to minimally invasive procedures and devices for implanting posterior instrumentation.
2. Description of the Related Art
The human vertebrae and associated connective elements are subject to a variety of diseases and conditions which cause pain and disability. Among these diseases and conditions are spondylosis, spondylolisthesis, vertebral instability, spinal stenosis and degenerated, herniated, or degenerated and herniated intervertebral discs. Additionally, the vertebrae and associated connective elements are subject to injuries, including fractures and torn ligaments and surgical manipulations, including laminectomies.
The pain and disability related to these diseases, conditions, injuries and manipulations often result from the displacement of all or part of a vertebra from the remainder of the vertebral column. A variety of methods have been developed to restore the displaced vertebrae or portions of displaced vertebrae to their normal position and to fix them within the vertebral column. For example, open reduction with screw fixation is one currently used method. The surgical procedure of attaching two or more parts of a bone with pins, screws, rods and plates requires an incision into the tissue surrounding the bone and the drilling of one or more holes through the bone parts to be joined. Due to the significant variation in bone size, configuration, and load requirements, a wide variety of bone fixation devices have been developed in the prior art. In general, the current standard of care relies upon a variety of metal wires, screws, rods, plates and clamps to stabilize the bone fragments during the healing or fusing process. These methods, however, are associated with a variety of disadvantages, such as morbidity, high costs, lengthy in-patient hospital stays and the pain associated with open procedures.
Therefore, devices and methods are needed for repositioning and fixing displaced vertebrae or portions of displaced vertebrae which cause less pain and potential complications. Preferably, the devices are implantable through a minimally invasive procedure.
SUMMARY OF THE INVENTIONIn accordance with one aspect of the present invention, a system is provided for the minimally invasive implantation of posterior fixation hardware. The system generally includes at least two bone anchors, at least one of which is provided with an adjustable connector. In many clinical situations, all of the bone anchors used in the system may be provided with adjustable connectors. The system may also include a driver for inserting the bone anchor into a bone and locking the adjustable connector. The system also includes at least one linkage rod, for linking two or More bone anchors through their respective adjustable connectors. In one embodiment, an insertion tool is provided for the insertion of the linkage rod. The bone anchors and the linkage rod may be fixed to each other by the locking of the adjustable connectors on the bone anchors, to subcutaneously form a prosthesis.
In accordance with another aspect of the present invention, the system additionally includes a guidance apparatus for the minimally invasive implantation of posterior fixation hardware. In one embodiment, the guidance apparatus includes a central support arm adapted to engage a bone anchor. A radial arm is pivotably attached to the central arm. A hollow access needle is secured to the radial arm. The radial arm is pivotable with respect to the central arm, to allow the hollow access needle to travel along an arcuate path, for guiding a guidewire through a tissue tract and into and through at least one adjustable connector on a bone anchor (or bone screw). The hollow access needle may removably carry an obturator, to facilitate percutaneous advancement. The hollow needle may additionally removably carry a distal guidewire capture device, for capturing a proximally advancing guidewire subcutaneously within the hollow access needle. The guidewire capture device may comprise a radially enlargeable structure such as a conical funnel, for deflecting an approaching guidewire into the lumen of the hollow access needle.
In another aspect of the present invention, a method is provided for the minimally invasive implantation of posterior fixation hardware. In one embodiment, the method comprises the insertion of a first bone anchor, having a first adjustable connector, into a first vertebral body. A second bone anchor, having a second adjustable connector, is inserted into a second vertebral body. The first and second vertebral bodies may be adjacent to each other, or separated by one or more other vertebral body or bodies. A linkage rod is inserted through the adjustable connectors of both bone anchors. The adjustable connector of each bone anchor is then locked, fixing the position of the adjustable connector within the bone anchor, and securing the linkage rod within the adjustable connector, to form a prosthesis.
In accordance with another embodiment of the present invention, the method further comprises the insertion of another bone anchor with an adjustable connector into another vertebral body. This latter vertebral body may be adjacent to either or both of the first and second vertebral bodies, or separated from both the first and second vertebral bodies. The linkage rod is inserted through the adjustable connectors of all of the bone anchors to form the prosthesis.
In accordance with another embodiment of the present invention, the method additionally includes the placement of one or more guide wires. A guide wire may be inserted into a bone to define a path for the insertion of a bone anchor. Another guide wire may be threaded through the adjustable connectors of two or more bone anchors, to guide the insertion of the linkage rod. The guide wire may be placed using the guidance apparatus described above.
In any of the foregoing systems and methods, the guide wire may be replaced or supplemented by a flexible guide tube. In such implementations of the invention, the bone anchor and/or the linkage rod may be advanced through the interior of the guide tube.
Further features and advantages of the present invention will become apparent to those skilled in the art in view of the detailed description of preferred embodiments which follows, when considered together with the attached drawings.
Although the application of the present invention will be disclosed primarily in the context of a spinal fixation procedure, the systems and methods disclosed herein are intended for use in a wide variety of medical applications where the minimally invasive implantation of an attachment, bulking, brace, support, fixation or other prosthesis may be desirable.
One advantage of the prosthesis formation described in the various embodiments of the present invention is the ability to access a treatment site through minimally invasive pathways, while allowing the formation of a relatively larger prosthesis at the treatment site. In one embodiment, various components of a prosthesis are inserted into a patient through minimally invasive pathways, then joined to form a single prosthesis. This is facilitated by the angularly adjustable connectors between the various components, which provide leeway or angular adjustability as the components are joined. Afterwards, the junctions between the various components may be locked to fix or set the prosthesis in a desired configuration.
A corollary advantage of several embodiments is the ability to unlock and adjust one or more junctions between components of the prosthesis, to set the prosthesis in other desirable configurations during or even after its implantation and formation. The prosthesis may thus be adjusted in subsequent procedures.
The systems and methods for spinal fixation according to various embodiments of the present invention minimize procedure morbidity by avoiding open surgical cutdowns or other invasive access procedures. The basic percutaneous access, bone screw construction and implantation methods, and methods and structures for percutaneously positioning a fixation rod across bone screws, all of which are useful in the practice of the present invention, are disclosed in U.S. patent application Ser. No. 09/747,066, entitled Percutaneous Vertebral Fusion System, to Teitelbaum, filed Dec. 21, 2000; U.S. patent application Ser. No. 09/943,636 to Shaolian et al., entitled Formable Orthopedic Fixation System, filed Aug. 29, 2001; U.S. patent application Ser. No. 09/976,459 to Teitelbaum et al., entitled Formable Orthopedic Fixation System with Cross-Linking, filed Oct. 10, 2001; and U.S. patent application Ser. No. 10/161,554 to Shaolian et al., entitled Formed in Place Fixation System with Thermal Acceleration, filed May 31, 2002; the disclosures of all of which arc hereby incorporated in their entireties by reference herein.
An overview of a system for minimally invasive posterior spinal fixation according to one embodiment of the present invention is provided in
The driver 150 comprises an outer adapter 152 concentrically arranged around an inner adapter 154. Either adapter may be freely rotated with respect to the other. The outer adapter 152 is adapted to engage the head 108, to screw the bone anchor 100 into a bone. The inner adapter 154 is adapted to engage the locking cap 106, to tighten the connector 104 within the head 108. In one embodiment, the hexagonal proximal end 156 of the outer adapter 152 allows torque to be applied to the outer adapter 152 by means of a wrench, a spanner or another tool. Similarly, the hexagonal proximal end 158 of the inner adapter 154 allows torque to be applied to the inner adapter 154.
Releasable, rotational engagement between the driver and the bone anchor may be accomplished in any of a variety of ways. In the illustrated embodiment, the distal end the inner adapter 154 is provided with at least one surface for cooperating with a complimentary surface on the proximal end of the bone anchor 100, for transmitting torque from the inner adapter 154 to the bone anchor 100, to enable transmission of torque from the inner adapter 154 to locking cap 106. Similarly, the distal end of the outer adapter 152 is provided with at least one surface for cooperating with a complimentary surface on the proximal end of the bone anchor 100, for transmitted torque from the outer adapter 152 to the bone anchor 100 to enable credible engagement between the bone anchor 100 and the vertebral body.
In one embodiment, the bone anchor 100, its connector 104, its locking cap 106, and the inner adapter 154 are all provided with a central axial lumen through which a guide wire 190 may pass.
In one embodiment, the connector 104 is seated on a race or groove 114 within the head 108. The groove 114 is preferably provided with a complementary surface to the spherical exterior surface of the connector 104. The connector 104 may rotate on any axis within the head 108 of the bone anchor (or bone screw) 100. A locking cap 106 may be threaded into the head 108 to lock the connector 104 against the linkage rod 200, by compressing the groove 114, fixing the connector 104 within the head 108. The bottom of the locking cap 106 may be provided with a concave surface (not shown) which is complementary to the spherical exterior surface of the connector 104.
A transverse portal 116 extends through the head 108 along an axis approximately perpendicular to the central axis of the bone anchor 100. While the aperture 110 of, the connector 104 and the transverse portal 116 of the head 108 are illustrated as circular, they may be of different shapes in other embodiments, depending upon the cross sectional shape of the fixation rod (e.g. oval, elliptical, rectangular, square, etc.). The diameter of the transverse portal 116 is generally smaller than the outside diameter of the uncompressed connector 104 but greater than the inside diameter of the aperture 110. Before the locking cap 106 is tightened, the connector 104 may rotate on any axis within the head 108 to accommodate different entrance angles for the fixation rod. Thus the central axis of the aperture 110 and the central axis of the transverse portal 116 may be coaxial or angularly offset.
In one embodiment, the threading of the locking cap 106 into the head 108 compresses the connector 104, decreasing the width of the gap 112 and reducing the cross sectional area of the aperture 110. This secures a linkage rod (not shown) extending through the transverse portal 116 of the bone anchor 100 within the aperture 110. The tightening of the locking cap 106 into the head 108 also fixes the rotational position of the connector 104 within the head 108.
In general, the rotation of the connector 104′ is limited such that the aperture will always be exposed through transverse portal 116 to the linkage rod 200. As can be seen, for example, in
In an alternate embodiment, portions or all of the connector 104 comprise a compressible media such as an open cell foam, closed cell foam or solid compressible material. Structures comprising polyethylene, PEEK, nylon, and other polymers known in the medical arts may be utilized, depending upon the construction and desired compressibility. In general, the combination of material and the structure of the connector 104 is sufficient to allow angular adjustment of the longitudinal axis of the aperture 110, to accommodate various entrance angles of the linkage rod 200. After the linkage rod 200 has been positioned within the aperture 110, rotational and/or axial movement of a locking element such as locking cap 106 functions to both prevent axial movement of the linkage rod 200 within the aperture 110, as well as prevent further angular adjustment of the longitudinal axis of the aperture 110 with respect to the longitudinal axis of the bone anchor 100.
In one embodiment, the apertures 110′ and 110″ have a tendency to return to their original diameters even after the connectors 104 and 104′, respectively, are compressed by the locking cap 106 against the groove 114 within the head 108. This tendency results from the resiliency of the metal, alloy or other material used to make the connectors 104 and 104′. The use of compressible material, such as V-shaped channels 113 in the gaps 112″ of the connector 104″, reduces or eliminates this tendency and may allow a linkage rod (not shown) to be more firmly secured within the aperture 110″. One skilled in the art will understand that the connectors 104 and 104′ can be made from lower resiliency materials which can also reduce or eliminate the tendency of apertures 110′ and 110″ to return to their original diameters.
As discussed above with reference to
Although specific interlocking relationships between the driver 150 and the bone anchor 100 are illustrated herein, the present inventors contemplate a variety of modifications. For example, the male-female relationship between the driver and the implant may be reversed, for either or both of the inner adaptor 154 and outer adapter 152. In addition, each of the inner adapter 154 and outer adapter 152 is provided with a surface structure for enabling rotational engagement with a corresponding component on the implant. Although this may be conveniently executed using corresponding hexagonal male and female components, any of a variety of alternative structures may be utilized in which a first surface on the inner adapter 154 or outer adapter 152 cooperates with a second, complementary surface on the corresponding aspect of the bone anchor 100, for allowing rotational engagement, followed by axial decoupling.
In
In one embodiment, both the linkage rod 200 and the control line 256 are provided with a central axial lumen for the passage over a guide wire.
The linkage rod 200 is provided with a hexagonal proximal end 202 adapted to engage a complementary hexagonal socket (not shown) in the distal end of the arm 252 of the insertion tool. In some embodiments, alternative complementary surface structures may be provided on the linkage rod 200 and the arm 252 to rotationally fix their orientation with respect to one another. In the illustrated embodiment, the hexagonal proximal end 202 is provided with a dimple 204 adapted to engage a complementary nub (not shown) within the hexagonal socket (not shown) in the distal end of the arm 252 of the insertion tool. The dimple 204 and nub (not shown) fix the axial orientation of the linkage rod 200 with respect to the arm 252. The threaded distal tip 262 of the control line 256 may be threaded into a complementary threaded hole 206 in the hexagonal proximal end 202 of the linkage rod 200, enabling the linkage rod 200 to be detachably secured to the arm 252 of the insertion tool. The threaded distal tip 262 may be threaded into the threaded hole 206 by rotating the knob (not shown) at the proximal end of the insertion tool. Unthreading the threaded distal tip 262 from the threaded hole 206 allows the linkage rod 200 to be released from the insertion tool 250.
In one embodiment, the outer adapter 152 is provided with an opening 160 extending along a diameter for fluoroscopic or other visualization of the rotational orientation of the outer adapter 152, to align the portal 116 of the bone anchor 100 engaged by the outer adapter 152. Towards this end, the axis of the opening 160 is preferably arranged at a right angle to the axis of the portal 116 as shown in
Alternatively, any of a variety of other indicium of the rotational orientation of the bone anchor 100 may be provided. For example, the complementary surface structures between the proximal end of the bone anchor 100 and the distal end of the insertion tool 250 may be configured to only allow coupling between the two components in a predetermined rotational orientation. In this construction, visual indicia may be provided on a portion of the insertion tool 250 (e.g. “T” handle, painted or etched markings or other indicium) which remains external to the patient, to allow direct visual observation of the rotational orientation of the longitudinal axis of the transverse portal 116.
In several embodiments, the components of the bone anchor, the linkage rod, the driver, and the arm of the insertion tool may be made of titanium, stainless steel or any other suitable metals, alloys, or material. The handle of the insertion tool is preferably made of a suitable non-slip material. The selection of these materials for the manufacture of the components and devices described in the above embodiments would be known by those skilled in the art.
Methods for the minimally invasive implantation of posterior fixation hardware according to embodiments of the present invention are disclosed in the context of a spinal fixation procedure with reference to
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A hollow access needle 450 is attached to the distal end 416 of the handle 410. In one embodiment, the access needle 450 is disposed within an opening 418 at the distal end 416 of the handle 410. A screw (not shown) may be threaded through a screw hole 420 at the distal end 416 of the handle 410 to tighten the access needle 450 within the opening 418. The lengthwise position of the access needle 450 within the opening 418 is therefore adjustable to allow the access needle 450 to be aimed through the transverse portal 116 of the bone anchor 100. In one embodiment, the access needle 450 may be aimed such that it passes through the transverse portal 116 at a point lower (towards the threads 102 in
In several embodiments, the sharp, tapered distal end 452 of the access needle 450 terminates at an opening 454. In one embodiment, the access needle 450 is provided with threaded proximal end 456, the purpose of which is described in further detail below.
In one embodiment of the present invention, the guide wire insertion device 400 additionally comprises a guide wire snare or capture device 530, illustrated in
In
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A flexible or curved bone drill (not shown) may be advanced along the guide wire 368 to clear a path between the transverse portals 116 of bone anchors 100 and 340. In one embodiment, the bone drill arm carrying the drill bit is provided with a certain degree of flexibility to allow it to travel along the arcuate course of the guide wire 368. In another embodiment, the curvature the bone drill arm carrying the drill bit is matched to the curvature of the linkage rod 200 to ensure that the path cleared between transverse portals 116 of bone anchors 100 and 340 fits the linkage rod 200. The bone drill is removed from the guide wire 368 after a path has been cleared between transverse portals 116 of bone anchors 100 and 340.
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In an embodiment of the body 401 having a circular cross sectional configuration, the diameter of the body 401 will generally be in the range of from about 3 mm to about 8 mm. In one embodiment, the diameter of the body 401 in a two level fusion device is about 6.35 mm. In general, the cross sectional area of the body 401, which may be expressed as a diameter in a circular cross sectional implementation, may be varied depending upon the desired structural integrity of the finished implant.
The distal end 404 of the body 401 may be provided with a distal opening 408 to a central guidewire lumen, not illustrated. The distal end 404 may also be provided with tapered tip 406 as has been previously discussed. In general, the tapered tip 406 may facilitate navigation through the tissue tract, as well as introduction of the body 401 into the bone anchor. Tapered tip 406 may be integrally formed with the body 401, or attached thereto in a subsequent manufacturing step.
The body 401 is generally provided with a preformed curve, such that it forms a portion of an arc as illustrated. In certain implementations of the invention, the arc has an approximately constant radius of curvature along the length the body 401. The radius of curvature of body 401 is generally in excess of about 19 cm, and, in many embodiments, within the range of from about 8 cm to about 30 cm. In one implementation of the invention, intended for a two level fusion, the overall length of the body 401 is about 65 mm, the diameter is about 6.35 mm, and the radius of curvature is about 19 cm.
The radius of curvature of the body 401 may be equal or approximately the same as the radius of curvature of the hollow access needle 450 in the guidewire insertion device 400 discussed previously. Thus, the radius may be approximately equal to the distance between the access needle 450 and the pivot point 414, which is also equal to the effective lever arm length of the handle 410. This facilitates introduction of the linkage rod 200 along the same curved tissue tract used by or created by the access needle 450.
The linkage rod 200 illustrated in
A similar locking configuration may be used in connection with the proximal bone anchor, and the proximal locking surface 412. Proximal locking surface 412 is carried by an axially moveable tubular collar 414. In the illustrated embodiment, the collar 414 comprises a generally tubular body axially movably carried by the body 401 of the linkage rod 200. The proximal locking surface 412 comprises a spherical, semi-spherical, curved or other enlargement in the cross-sectional area collar 414, to provide a locking surface which may be useful throughout a variety of angular orientations as has described. One or two or three or four more axially extending slots 416 may be provided on the proximal lock, to facilitate compression of the lock from a slideable orientation to a locked orientation in which it is compressed against the body 401. In the illustrated embodiment, two or more axially extending slots extend in a proximal direction from the distal end of the lock.
In use, the linkage rod 200 is advanced distally along a guidewire, through a tube, or otherwise through the first and second bone anchors. With the distal locking surface 410 positioned within the proximal head 108 of the distal bone anchor, the locking cap 106 of the distal bone anchor is tightened to lock the linkage rod 200 with respect the distal bone anchor. The proximal lock is thereafter axially distally advanced along the insertion tool and/or linkage rod 200, until the proximal locking surface 412 is positioned within the head 108 of the proximal bone anchor. The locking cap 106 of the proximal bone anchor is tightened, to lock the proximal locking surface 412 against the body 401.
The proximal lock may be distally advanced along the insertion tool and/or linkage rod 200 in any of a variety of manners, such as by distally advancing a pusher sleeve which is axially movably carried on the insertion tool.
In one embodiment, the transverse portal 116 of the proximal bone anchor is provided with a proximal opening having a first diameter and distal opening having a second, smaller diameter. The outside diameter of proximal locking surface 412 is dimensioned relative to the portal 116 such that it can pass through the proximal opening on the transverse portal 116 but cannot pass distally through the distal opening of the transverse portal 116. In this manner, the clinician can perceive tactile feedback once the proximal lock has been distally advanced into position within the head 108. This same construction can be utilized on the distal bone anchor as well, such that distal advancement of the distal locking surface 410 may be accomplished until the positive stop is felt by the clinician as the distal locking surface 410 is seated within the head 108. The driver tool can be provided with indicium of the rotational position of the bone anchor.
In all of the foregoing embodiments, the insertion tool may be provided with a curved distal region, having a radius of curvature which approximates the radius of curvature of the linkage rod, described above. Thus, in one embodiment both the linkage rod 200 and the distal portion of the insertion tool are provided with a curve having a radius of approximately 12 cm. This further facilitates introduction of the linkage rod and insertion tool along a curved tissue tract, while minimizing trauma to surrounding tissue, as the linkage rod 200 is navigated through the first and second bone anchors.
The foregoing construction also allows the percutaneous access site for the introduction of the linkage rod 200 to be predetermined distance from the longitudinal axis of the driver 150. For example, in one implementation of the guidance system, the radius of curvature of the curved needle 450 is approximately 9 cm. This enables the percutaneous access site to be approximately 8 centimeters from the percutaneous entry site for the driver 150. The transdermal access site for the linkage rod is preferably no more than about one radius away from the driver 150. This allows minimization of the length of the tissue tract, and thus minimizes the access induced trauma to surrounding tissue.
Not all of the steps described above are critical to the minimally invasive implantation of posterior fixation hardware. Accordingly, some of the described steps may be omitted or performed in an order different from that disclosed. Further, additional steps may be contemplated by those skilled in the art in view of the disclosure herein, without departing from the scope of the present invention.
The present inventors contemplate the interchangeability of and recombination of various structural and method elements in the foregoing description. For example, the guidewire may be positioned through portals of adjacent bone anchors utilizing either the procedures disclosed in the copending patent applications previously incorporated by reference herein. Alternatively, the guidewire may be positioned utilizing the pivotable guidance system disclosed herein. As a further alternative, a tubular sleeve may be advanced over the guidewire and through the portals on bone anchors 100, with the guidewire thereafter removed. The linkage rod 200 may thereafter be advanced through the tubular sleeve.
The linkage rod 200 may be advanced utilizing the manual insertion tool 250, as disclosed herein. Alternatively, the linkage rod 200 may be releasably connected to the distal end of a curved pivotable arm 450, using releasable connection structures disclosed elsewhere herein. In this manner, the pivotable insertion system such as that illustrated in
The various materials, methods and techniques described above provide a number of ways to carry out the invention. Of course, it is to be understood that not necessarily all objectives or advantages described may be achieved in accordance with any particular embodiment described herein. Thus, for example, those skilled in the art will recognize that the components of the system may be made and the methods may be performed in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objectives or advantages as may be taught or suggested herein.
Although the present invention has been described in terms of certain preferred embodiments, other embodiments of the invention including variations in dimensions, configuration and materials will be apparent to those of skill in the art in view of the disclosure herein. In addition, all features discussed in connection with any one embodiment herein can be readily adapted for use in other embodiments herein. The use of different terms or reference numerals for similar features in different embodiments does not imply differences other than those which may be expressly set forth. Accordingly, the present invention is intended to be described solely by reference to the appended claims, and not limited to the preferred embodiments disclosed herein.
Claims
1. A prosthesis assembly for minimally invasive posterior fixation, comprising:
- a curved rod, having a proximal end and a distal end, and releasable coupling on the proximal end; and
- a bone anchor provided with an adjustable connector, said adjustable connector including a lock to securely engage said rod at any of a variety of angular orientations between the rod and the bone anchor.
2. The prosthesis assembly of claim 1 further comprising a second bone anchor having a connector adapted to securely engage said rod.
3. The prosthesis assembly of claim 1, wherein the bone anchor comprises a head and a rotatable connector disposed within said head, said rotatable connector adapted to securely engage said rod.
4. A prosthesis for minimally invasive posterior fixation, comprising:
- a bone anchor having a head;
- a transverse portal extending through said head along an axis transverse to a central axis of said bone anchor;
- a rod extending through said transverse portal;
- a rotating connector with an aperture seated in a groove within said head; said aperture adapted to securely engage said rod; and
- a locking cap which secures said rotating connector against said groove and said rod within said aperture.
5. The prosthesis of claim 4, wherein said rotating connector further comprises indentations on its exterior adapted to cooperate with complementary projections within said head to limit the rotation of said rotating connector.
6. The prosthesis of claim 4, wherein said rotating connector further comprises at least one compression gap.
7. The prosthesis of claim 4, wherein said rod is adapted to be detachably secured to an insertion tool used to insert said rod into said aperture.
8. A guide wire introducer for inserting a guide wire through a transverse portal of a bone anchor, comprising:
- an adapter aligned with a central axis of said bone anchor;
- a handle attached at a pivot to said adapter; and
- an access needle on said handle adapted for insertion through said transverse portal of said bone anchor.
9. The guide wire apparatus of claim 8 further comprising an obturator.
10. The guide wire apparatus of claim 8 further comprising a guide wire capture device.
11. The guide wire apparatus of claim 10 wherein said guide wire capture device further comprises a retractable conical funnel.
12-16. (canceled)
17. A guide wire insertion device to insert a guide wire through a portal of a bone anchor, comprising:
- A central arm adapted to engage said bone anchor;
- A radial arm attached to said central arm at a pivot;
- A hollow access needle secured to said radial arm;
- Wherein said radial arm pivots on said pivot to move said access needle through said port of said bone anchor.
18. The guide wire insertion device of claim 17, further comprising a guide wire capture device.
19. The guide wire insertion device of claim 18 wherein said guide wire capture device further comprises a conical receiving end which comprises one or more partial conical segments.
20-39. (canceled)
Type: Application
Filed: Oct 12, 2012
Publication Date: Feb 7, 2013
Applicant: WARSAW ORTHOPEDIC, INC (Warsaw, IN)
Inventor: Warsaw Orthopedic, Inc (Warsaw, IN)
Application Number: 13/650,390
International Classification: A61B 17/70 (20060101); A61B 17/90 (20060101);