SYSTEM AND METHOD FOR FACET JOINT REPLACEMENT WITH DETACHABLE COUPLER

• US 20080319483A1
• Filed: 08/29/2008
• Published: 12/25/2008
• Est. Priority Date: 01/10/2007
• Status: Active Grant

• Current Assignee: Globus Medical, Inc.
• Original Assignee: Facet Solutions, Inc. (Globus Medical, Inc.)
• Inventors: Fauth, Andrew R., Triplett, Daniel J., Helgerson, Joel R.
• Granted Patent: US 8,206,418 B2
• Time in Patent Office: Days
• US Class Current: 606/246
• 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 17/7035 Screws or hooks, wherein a rod-clamping part and a bone-anchoring part can pivot relative to each other
• CPC Class Codes: A61B 17/704 the longitudinal element passing through a ball-joint in the screw head
• CPC Class Codes: A61B 17/7064 Devices acting on, attached to, or simulating the effect of, vertebral facets; Tools therefor
• CPC Class Codes: A61B 17/7067 Devices bearing against one or more spinous processes and also attached to another part of the spine; Tools therefor
• CPC Class Codes: A61B 17/707 Devices acting on, or attached to, a transverse process or rib; Tools therefor
• CPC Class Codes: A61B 2017/7073 with intervertebral connecting element crossing an imaginary spinal median surface
• CPC Class Codes: A61F 2/0095 Packages or dispensers for prostheses or other implants for intraocular lenses A61F2/1691; for dental surgery A61C19/02
• CPC Class Codes: A61F 2/4405 for apophyseal or facet joints, i.e. between adjacent spinous or transverse processes devices implanted between spinous or transverse processes A61B17/7062
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2002/30331 made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30471 connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2002/30481 using a locking clip
• CPC Class Codes: A61F 2002/30495 using a locking ring
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30522 releasable, e.g. using a releasable ratchet
• CPC Class Codes: A61F 2002/30537 adjustable
• CPC Class Codes: A61F 2002/3054 : about a connection axis or implantation axis for selecting any one of a plurality of radial orientations between two modular parts, e.g. Morse taper connections, at discrete positions, angular positions or continuous positions
• CPC Class Codes: A61F 2002/3055 : for adjusting length
• CPC Class Codes: A61F 2002/30604 : modular
• CPC Class Codes: A61F 2002/30649 : Ball-and-socket joints
• CPC Class Codes: A61F 2002/30841 : Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30845 : with cutting edges
• CPC Class Codes: A61F 2002/3085 : with a threaded, e.g. self-tapping, bone-engaging surface, e.g. external surface
• CPC Class Codes: A61F 2002/30884 : Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/30904 : serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/448 : comprising multiple adjacent spinal implants within the same intervertebral space or within the same vertebra, e.g. comprising two adjacent spinal implants
• CPC Class Codes: A61F 2002/449 : comprising multiple spinal implants located in different intervertebral spaces or in different vertebrae
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2220/0091 : connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2250/0004 : adjustable
• CPC Class Codes: A61F 2250/0007 : for adjusting length
• CPC Class Codes: A61F 2310/00796 : Coating or prosthesis-covering structure made of a phosphorus-containing compound, e.g. hydroxy(l)apatite

Abstract

A facet joint replacement system includes an inferior implant with an inferior articular surface, and a superior implant with a superior articular surface. The implants may be coupled together by a detachable coupler which can align and rigidly hold the inferior and superior articular surfaces in a preferred alignment relative to one another. A portion of the coupler may be deformable to allow detachment of the coupler from at least one of the implants. In one method of implantation, the superior and inferior implants may be aligned and coupled together with the coupler, and then secured to fixation members anchored in adjacent vertebrae. Alternatively, a first implant may be secured to a fixation member anchored in a first vertebra, and a second implant coupled to the coupler, aligned with the first implant and then secured to a fixation member anchored in a second vertebra. A tool may grip, position and/or deliver the coupler and the implants.

Claims

1. A system comprising:

a superior facet joint implant comprising a superior articular surface shaped to replace a natural superior articular surface of a first vertebra;

an inferior facet joint implant comprising an inferior articular surface shaped to replace a natural inferior articular surface of a second vertebra superior to the first vertebra; and

a deformable coupler detachably coupled to the superior and inferior facet joint implants to keep the superior and inferior facet joint implants in a desired relative position.

2. The system of claim 1, wherein the inferior facet joint implant further comprises an inferior fixation portion attachable to a pedicle of the second vertebra.

3. The system of claim 1, wherein the coupler is deformable from a locked position in which the coupler is locked to at least one of the superior and inferior facet joint implants, to a unlocked position in which the coupler is detached from at least one of the superior and inferior facet joint implants.

4. The system of claim 2, wherein the superior facet joint implant further comprises a superior fixation portion attachable to a pedicle of the first vertebra;

wherein the superior fixation portion is displaced from the superior articular surface and the inferior fixation portion is displaced from the inferior articular surface.

5. The system of claim 1, wherein the coupler comprises a clip comprising:

a superior facet joint implant receiver shaped to detachably receive the superior facet joint implant ; and

an inferior facet joint implant receiver shaped to detachably receive the inferior facet joint implant.

6. The system of claim 1, wherein the coupler further comprises:

a rigid alignment feature shaped to hold the superior articular surface and the inferior articular surface in a fixed relative position; and

a deformable retention feature shaped to flex to facilitate detachment of the coupler from at least one of the superior and inferior facet joint implants.

7. The system of claim 1, wherein at least a portion of the coupler is shaped to flex to facilitate detachment of the coupler from at least one of the superior and inferior facet joint implants.

8. The system of claim 7, wherein a portion of the coupler comprises a post, the post comprising two opposably arranged ends, wherein upon removal of a wire positioned between the ends, the ends are able to move toward one another to facilitate detachment of the coupler from at least one of the superior and inferior facet joint implants.

9. The system of claim 1, wherein the coupler is of one-piece construction.

10. The system of claim 2, wherein an orientation of the inferior articular surface is polyaxially adjustable relative to the inferior fixation portion after attachment of the inferior fixation portion to the pedicle of the second vertebra.

11. The system of claim 2, wherein an offset distance between the inferior articular surface and the pedicle of the second vertebra is adjustable after attachment of the inferior fixation portion to the pedicle of the second vertebra.

12. A method comprising:

positioning an assembly proximate a natural facet joint of a spine, the assembly comprising a superior facet joint implant comprising a superior articular surface shaped to replace a natural superior articular surface of a first vertebra of the spine, an inferior facet joint implant comprising an inferior articular surface shaped to replace a natural inferior articular surface of a second vertebra of the spine, and a deformable coupler coupled to the superior and inferior facet joint implants;

securing the superior facet joint implant to the first vertebra of the spine;

securing an inferior fixation portion of the inferior facet joint implant to a pedicle of the second vertebra of the spine; and

detaching the coupler from the superior and inferior facet joint implants.

13. The method of claim 12, wherein detaching the coupler from the superior and inferior facet joint implants comprises deforming at least a portion of the coupler.

14. The method of claim 13, wherein a portion of the coupler comprises a post, the post comprising two opposably arranged ends, wherein detaching the coupler from the superior and inferior facet joints comprises removing a wire positioned between the ends.

15. The method of claim 12, wherein securing the superior facet joint implant to the first vertebra comprises securing a superior fixation portion of the superior facet joint implant to a pedicle of the first vertebra;

wherein the superior fixation portion is displaced from the superior articular surface and the inferior fixation portion is displaced from the inferior articular surface.

16. The method of claim 12, wherein detaching the coupler from the superior and inferior facet joint implants comprises withdrawing the superior facet joint implant from a superior facet joint implant receiver of the coupler and withdrawing the inferior facet joint implant from an inferior facet joint implant receiver of the coupler.

17. The method of claim 12, wherein the coupler is of one-piece construction.

18. The method of claim 12, further comprising polyaxially adjusting an orientation of the inferior articular surface relative to the inferior fixation portion after securing the inferior fixation portion of the inferior facet joint implant to a pedicle of the second vertebra of the spine.

19. The method of claim 12, further comprising adjusting an offset distance between the inferior articular surface and the second pedicle of the spine after securing the inferior fixation portion of the inferior facet joint implant to a pedicle of the second vertebra of the spine.

20. A method comprising:

securing a superior facet joint implant to a first vertebra of a spine, the superior facet joint implant comprising a superior articulation portion;

positioning an assembly proximate the first vertebra and a second vertebra of the spine, the assembly comprising an inferior articulation portion coupled to an inferior fixation portion of an inferior facet joint implant, and a coupler coupled to the inferior articulation portion; and

coupling the coupler to the superior facet joint implant after securement of the superior facet joint implant to the first vertebra such that the inferior facet joint implant is aligned with the superior facet joint implant in a desired relative position.

21. The method of claim 20, further comprising securing the inferior fixation portion of the inferior facet joint implant to the pedicle of the second vertebra of the spine.

22. The method of claim 20, further comprising:

locking the inferior articulation portion of the inferior facet joint implant to the inferior fixation portion of the inferior facet joint implant at a desired relative orientation; and

detaching the coupler from the inferior and superior facet joint implants.

23. The method of claim 22, wherein detaching the coupler from the inferior and superior facet joint implants comprises deforming the coupler.

24. The method of claim 22, wherein the coupler comprises a rigid alignment feature and a deformable retention feature, wherein detaching the coupler from at least one of the inferior and superior facet joint implants comprises flexing the deformable retention feature.

25. The method of claim 20, wherein the coupler is of one-piece construction.

26. The method of claim 20, wherein the inferior articulation portion comprises an inferior articular surface shaped to replace a natural inferior articular surface of the second vertebra, and wherein the superior articulation portion comprises a superior articular surface shaped to replace a natural superior articular surface of the first vertebra.

27. A method comprising:

securing a first fixation assembly to a first vertebra of a spine;

positioning an assembly proximate the first vertebra and a second vertebra of a spine, the assembly comprising;

a superior articulation portion of a superior facet joint implant;

an inferior articulation portion of an inferior facet joint implant; and

a deformable coupler coupled to the superior and inferior articulation portions to keep the superior and inferior articulation portions in a desired relative position; and

coupling a superior fixation portion of the superior facet joint implant to the first fixation assembly after securement of the first fixation assembly to the first vertebra.

28. The method of claim 27, wherein the inferior facet joint implant further comprises a strut comprising an inferior fixation portion, the method further comprising:

coupling the strut to the inferior articulation portion; and

coupling the inferior fixation portion to a second fixation assembly secured to a pedicle of the second vertebra.

29. The method of claim 27, further comprising detaching the deformable coupler from the superior and inferior articulation portions.

30. The method of claim 29, wherein the coupler comprises a deformable retention feature, wherein detaching the coupler from at least one of the inferior and superior facet joint implants comprises deforming the deformable retention feature.

31. The method of claim 27, wherein the inferior articulation portion comprises an inferior articular surface shaped to replace a natural inferior articular surface of the second vertebra, and wherein the superior articulation portion comprises a superior articular surface shaped to replace a natural superior articular surface of the first vertebra.

32. The method of claim 28, wherein coupling the strut of the inferior facet joint implant to the inferior articulation portion further comprises:

polyaxially rotating the inferior fixation portion of the strut to a desired orientation relative to the inferior articulation portion; and

actuating an attachment mechanism to rigidly secure the strut to the inferior articulation portion.

33. The method of claim 28, wherein coupling the inferior fixation portion of the inferior facet joint implant to the second fixation assembly further comprises:

adjusting an offset distance between the inferior fixation portion and the second fixation assembly to a desired distance; and

actuating an attachment mechanism to rigidly secure the inferior fixation portion to the second U ¢

fixation assembly.