Implant assembly and method for use in an internal structure stabilization system

• US 7,618,442 B2
• Filed: 11/16/2004
• Issued: 11/17/2009
• Est. Priority Date: 10/21/2003
• Status: Expired due to Term

• Current Assignee: Theken Spine LLC (Orthofix Medical Inc.)
• Original Assignee: Theken Spine LLC (Orthofix Medical Inc.)
• Inventors: Colleran, Dennis, Spitler, James, Schorer, Scott
• Primary Examiner(s): Robert; Eduardo C
• Assistant Examiner(s): HOFFMAN, MARY C
• Application Number:
  US10/990,272
• Publication Number:
  US 20060036244A1
• Time in Patent Office: 1,827 Days
• Field of Search: 606/61, 606 71- 72, 606/86.A, 606/916, 606/914
• US Class Current: 606/266
• CPC Class Codes: A61B 17/1604 Chisels; Rongeurs; Punches; Stamps
• CPC Class Codes: A61B 17/1655 for tapping
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 17/320016 Endoscopic cutting instruments, e.g. arthroscopes, resectoscopes A61B10/0233, A61B17/29, A61B17/3207 take precedence
• CPC Class Codes: A61B 17/3417 Details of tips or shafts, e.g. grooves, expandable, bendable; Multiple coaxial sliding cannulas, e.g. for dilating syringe needles A61M5/32; dilators A61M29/00
• CPC Class Codes: A61B 17/3421 Cannulas
• CPC Class Codes: A61B 17/3468 for implanting or removing devices, e.g. prostheses, implants, seeds, wires devices for implanting seeds A61M37/0069
• CPC Class Codes: A61B 17/7002 Longitudinal elements, e.g. rods
• CPC Class Codes: A61B 17/7005 Parts of the longitudinal elements, e.g. their ends, being specially adapted to fit in the screw or hook heads
• CPC Class Codes: A61B 17/701 Longitudinal elements with a non-circular, e.g. rectangular, cross-section A61B17/7005, A61B17/7007 take precedence
• CPC Class Codes: A61B 17/7011 Longitudinal element being non-straight, e.g. curved, angled or branched adjustable length longitudinal elements A61B17/7014; A61B17/7019 takes precedence, e.g. coil springs
• CPC Class Codes: A61B 17/7032 Screws or hooks with U-shaped head or back through which longitudinal rods pass
• CPC Class Codes: A61B 17/7037 wherein pivoting is blocked when the rod is clamped
• CPC Class Codes: A61B 17/7038 to a different extent in different directions, e.g. within one plane only
• CPC Class Codes: A61B 17/704 the longitudinal element passing through a ball-joint in the screw head
• CPC Class Codes: A61B 17/7082 for driving, i.e. rotating, screws or screw parts specially adapted for spinal fixation, e.g. for driving polyaxial or tulip-headed screws driving other bone screws A61B17/8875
• CPC Class Codes: A61B 17/7085 for insertion of a longitudinal element down one or more hollow screw or hook extensions, i.e. at least a part of the element within an extension has a component of movement parallel to the extension's axis
• CPC Class Codes: A61B 17/7091 for applying, tightening or removing longitudinal element-to-bone anchor locking elements, e.g. caps, set screws, nuts or wedges
• CPC Class Codes: A61B 2017/320044 Blunt dissectors
• CPC Class Codes: A61B 2090/061 for measuring dimensions, e.g. length
• CPC Class Codes: A61B 2090/067 : for measuring angles
• CPC Class Codes: A61B 5/103 : Detecting, measuring or recording devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes A61B5/08 takes precedence; measuring aids for tailors A41H1/00; measuring instruments specially adapted for dentistry A61C19/04
• CPC Class Codes: A61B 5/107 : Measuring physical dimensions, e.g. size of the entire body or parts thereof
• CPC Class Codes: A61B 5/4504 : Bones A61B5/4547 takes precedence
• CPC Class Codes: A61B 5/6878 : Bone
• CPC Class Codes: A61B 5/6882 : Anchoring means
• CPC Class Codes: Y10T 74/22 : Miscellaneous

Abstract

An assembly for use in spinal stabilization procedures having first and second bone anchor assemblies. Embodiments of the first bone anchor assembly may include an anchor, a poly-axial head, including a cavity, mated with the anchor such that the anchor is movable relative to the poly-axial head. Embodiments of the second bone anchor assembly may include an anchor, a poly-axial head mated with the second anchor such that the anchor is movable relative to the poly-axial head, a slide ring rotatably mated in the second poly-axial head, and a connector slideably mated in the slide ring along a distal end, and having a proximal end having an enlarged portion. The connector may be movable from a first position axially inline with the second bone anchor to a second position wherein the enlarged portion of the connector rests in the cavity of the first poly-axial head.

Claims

1. An assembly for use in spinal stabilization procedures, comprising:

a first bone anchor assembly comprising;

a first anchor

a first poly-axial head mated with the anchor such that the anchor is movable in relation to the poly-axial head, the first poly-axial head including a cavity; and

a second bone anchor assembly comprising;

a second anchor;

a second poly-axial head mated with the second anchor such that the second anchor is movable in relation to said second poly-axial head;

a slide ring rotatably mated in the second poly-axial head;

a connector slidably mated in the slide ring along a distal end, and having a proximal end having an enlarged portion;

wherein the connector is movable from a first position axially inline with the second bone anchor to a second position wherein the enlarged portion of the connector rests in the cavity of the first poly-axial head, and wherein the first position is used to implant the first bone anchor assembly, and the second position used to hold the assembly in a fixed orientation; and

a snap ring in the first poly-axial head, the snap ring holding the enlarged portion of the connector in the cavity.

2. The assembly of claim 1, further comprising locking caps inserted into the first and the second poly-axial heads, wherein the locking caps act to lock the elements of the first and second bone anchor assemblies into a fixed orientation.

3. The assembly of claim 2, wherein said locking caps comprise:

a locking ring insertable into said second poly-axial head and operable to hold said slide ring, said first poly-axial head and said first anchor in a fixed orientation; and

a compression cap insertable into said locking ring and operable to hold said connector in a fixed orientation with said slide ring.

4. The assembly of claim 1, further comprising an extension removably attached to the first poly-axial head assembly, the extension allowing access to the first bone anchor assembly after implantation.

5. The assembly of claim 4 wherein the extension comprises:

a tubular body having an attachment mechanism for attaching to the first poly-axial head; and

a locking mechanism for temporarily locking the extension with the first poly-axial head.

6. The assembly of claim 5 wherein the locking mechanism is a twist ring and a slider attached to the tubular body, the twist ring twistable to cause the slider to move between a first and second position, the first position temporarily locking the extension to the first poly-axial head, the second position allowing the extension to be disengaged from the first poly-axial head.

7. The assembly of claim 1 wherein the first anchor includes an off-axis guide from a tip of the first anchor out a side of the first anchor, the off-axis guide allowing the first anchor to be guided down a guide wire.

8. The assembly of claim 1 wherein the connector includes a drive mechanism mated to a drive mechanism of the second anchor when the connector is in the first position, the connector operable in the first position to transfer torque from a tool to the second anchor.

9. The assembly of claim 1 wherein the connector includes an engagement mechanism in the enlarged portion, the engagement mechanism for engaging with a connector transfer tool.

10. An assembly for use in spinal stabilization procedures, comprising:

a first bone anchor assembly comprising;

a first anchor

a first poly-axial head mated with the anchor such that the anchor is movable in relation to the poly-axial head, the first poly-axial head including a cavity; and

a second bone anchor assembly comprising;

a second anchor;

a second poly-axial head mated with the second anchor such that the second anchor is movable in relation to said second poly-axial head;

a slide ring rotatably mated in the second poly-axial head;

a connector slidably mated in the slide ring along a distal end, and having a proximal end having an enlarged portion;

wherein the connector is movable from a first position axially inline with the second bone anchor to a second position wherein the enlarged portion of the connector rests in the cavity of the first poly-axial head, and wherein the first position is used to implant the first bone anchor assembly, and the second position used to hold the assembly in a fixed orientation; and

wherein the connector includes a drive mechanism mated to a drive mechanism of the second anchor when the connector is in the first position, the connector operable in the first position to transfer torque from a tool to the second anchor.

11. The assembly of claim 10, further comprising a snap ring in the first poly-axial head, the snap ring holding the enlarged portion of the connector in the cavity.

12. The assembly of claim 10, further comprising locking caps inserted into the first and the second poly-axial heads, wherein the locking caps act to lock the elements of the first and second bone anchor assemblies into a fixed orientation.

13. The assembly of claim 12, wherein said locking caps comprise:

a locking ring insertable into said second poly-axial head and operable to hold said slide ring, said first poly-axial head and said first anchor in a fixed orientation; and

a compression cap insertable into said locking ring and operable to hold said connector in a fixed orientation with said slide ring.

14. The assembly of claim 10, further comprising an extension removably attached to the first poly-axial head assembly, the extension allowing access to the first bone anchor assembly after implantation.

15. The assembly of claim 14, wherein the extension comprises:

a tubular body having an attachment mechanism for attaching to the first poly-axial head; and

a locking mechanism for temporarily locking the extension with the first poly-axial head.

16. The assembly of claim 15, wherein the locking mechanism is a twist ring and a slider attached to the tubular body, the twist ring twistable to cause the slider to move between a first and second position, the first position temporarily locking the extension to the first poly-axial head, the second position allowing the extension to be disengaged from the first poly-axial head.

17. The assembly of claim 10, wherein the first anchor includes an off-axis guide from a tip of the first anchor out a side of the first anchor, the off-axis guide allowing the first anchor to be guided down a guide wire.

18. The assembly of claim 10, wherein the connector includes an engagement mechanism in the enlarged portion, the engagement mechfanism for engaging with a connector transfer tool.