Implant system, method, and instrument for augmentation or reconstruction of intervertebral disc

• US 20060085002A1
• Filed: 10/14/2004
• Published: 04/20/2006
• Est. Priority Date: 10/14/2004
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: SDGI Holdings Incorporated (Medtronic Plc)
• Inventors: Trieu, Hai H., Li, Lehmann K.
• Granted Patent: US 7,682,393 B2
• Time in Patent Office: Days
• US Class Current: 623/17.110
• CPC Class Codes: A61B 17/1631 Special drive shafts, e.g. flexible shafts A61B17/1642, A61B17/164 take precedence
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1728 for holes for bone plates or plate screws
• CPC Class Codes: A61B 17/8875 Screwdrivers, spanners or wrenches
• CPC Class Codes: A61B 17/8886 holding the screw head
• CPC Class Codes: A61F 2/08 Muscles; Tendons; Ligaments sutures A61B17/04
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30069 elastomeric
• CPC Class Codes: A61F 2002/30266 wedge-shaped parallelepipeds
• 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 2002/30387 Dovetail connection
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30772 Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/4435 Support means or repair of the natural disc wall, i.e. annulus, e.g. using plates, membranes or meshes
• CPC Class Codes: A61F 2002/444 : for replacing the nucleus pulposus
• 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 2002/4627 : with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2210/0004 : bioabsorbable
• 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 2230/0082 : parallelepipedal
• CPC Class Codes: A61F 2310/00017 : Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 : Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00161 : Carbon; Graphite
• CPC Class Codes: A61F 2310/00167 : Diamond or diamond-like carbon
• CPC Class Codes: A61F 2310/00203 : containing alumina or aluminium oxide
• CPC Class Codes: A61F 2310/00239 : containing zirconia or zirconium oxide ZrO2
• CPC Class Codes: A61F 2310/00359 : Bone or bony tissue
• CPC Class Codes: A61F 2310/00365 : Proteins; Polypeptides; Degradation products thereof

Abstract

An augmentation instrument for attaching a retaining device to a vertebral endplate comprises a drive housing having a distal end portion, a drive mechanism extending through the drive housing and including a flexible shaft portion, and an attachment mechanism at the distal end portion of the drive housing. The attachment mechanism is adapted for coupling to the retaining device.

Claims

1. A system to prevent migration of a nucleus prosthesis disposed between a pair of vertebral endplates, the system comprising:

a first buttress plate having a mounting face and a retaining face, wherein the mounting surface is a disposed generally perpendicular to the retaining surface and;

a fastener inserted through the mounting surface and into only one of the vertebral endplates,

wherein the first buttress plate is located entirely between the pair of vertebral endplates.

2. The system of claim 1 wherein the first buttress plate has a wedge shape.

3. The system of claim 1 wherein the retaining face has a length greater than half of a distance between the vertebral endplates.

4. The system of claim 1 wherein the mounting face includes a roughened surface texture.

5. The system of claim 1 wherein the retaining face is smooth.

6. The system of claim 1 wherein the mounting face is at least partially coated with hydroxyapetite.

7. The system of claim 1 wherein the fastener is a screw.

8. The system of claim 1 wherein the fastener is at least partially coated with hydroxyapetite.

9. The system of claim 1 wherein the first buttress plate comprises titanium.

10. The system of claim 1 wherein the first buttress plate comprises polyetheretherketone.

11. The system of claim 1 further comprising an annular plug.

12. The system of claim 1 wherein the retaining face is lined with ultra high molecular weight polyethylene.

13. The system of claim 1 wherein the first buttress plate includes a tapered portion adapted to extend between an annulus wall and the nucleus prosthesis.

14. The system of claim 1 further comprising a second buttress plate for preventing migration of the nucleus prosthesis.

15. The system of claim 14 wherein the first buttress plate overlaps the second buttress plate.

16. An assembly for repairing an annular defect area to prevent migration of a nucleus prosthesis, the system comprising:

a first blocking plate for blocking migration of the intervertebral implant through the annular defect area, the first blocking plate positioned within an intervertebral disc space defined by a pair of vertebral endplates; and

a threaded connector for attaching the first blocking plate to a single one of the vertebral endplates.

17. The assembly of claim 16 wherein the first blocking plate occupies greater than half of the annular defect area.

18. The assembly of claim 16 wherein a portion of the first blocking plate includes a wear-resistant surface interfacing with the nucleus prosthesis.

19. The assembly of claim 16 wherein a portion of the first blocking plate includes a cushioned surface interfacing with the nucleus prosthesis.

20. An augmentation instrument for attaching a retaining device to a vertebral endplate, the augmentation instrument comprising:

a drive housing having a distal end portion;

a drive mechanism extending through the drive housing and including a flexible shaft portion; and

an attachment mechanism at the distal end portion of the drive housing,

wherein the attachment mechanism is adapted for coupling to the retaining device.

21. The augmentation instrument of claim 20 wherein the drive mechanism further includes a drill tip.

22. The augmentation instrument of claim 20 wherein the drive mechanism further includes a screwdriver tip.

23. The augmentation instrument of claim 20 further comprising a bending actuator for bending the drive mechanism at the flexible shaft portion.

24. The augmentation instrument of claim 20 wherein the attachment mechanism includes a selector for releasing the retaining device from the augmentation instrument.

25. The augmentation instrument of claim 20 wherein the distal end portion is angled to bend the drive mechanism at the flexible shaft portion.

26. The augmentation instrument of claim 20 further comprising a stabilizer extending from the distal end portion.

27. A method for retaining a prosthesis in an intervertebral disc space, the method comprising:

attaching a retaining device to an augmentation instrument;

bending a first flexible drive shaft to drill a hole in a vertebral endplate;

inserting a fastener through the retaining device;

bending a second flexible drive shaft to drive the fastener into the hole; and

releasing the retaining device from the augmentation instrument.

28. The method of claim 27 further comprising:

inserting a distal portion of the augmentation instrument into the intervertebral disc space.

29. The method of claim 27 further comprising:

inserting the first flexible drive shaft through a bore in the augmentation instrument.

30. The method of claim 27 further comprising:

deploying an actuator to bend the first flexible drive shaft.

31. The method of claim 27 further comprising:

installing an annular plug adjacent to the retaining device.

32. The method of claim 27 wherein the first flexible drive shaft is the second flexible drive shaft.

33. The method of claim 27 further comprising:

deploying a stabilizer to engage a vertebral body.

34. A method for preventing migration of a prosthesis from an intervertebral disc space, the method comprising:

providing a retaining device, the retaining device including a blocking face disposed generally perpendicular to a mounting face;

positioning the blocking face within the intervertebral disc space to prevent migration of the prosthesis; and

securing the mounting face to a vertebral endplate, wherein the retaining device is entirely within the intervertebral disc space.

35. The method of claim 34 further comprising:

positioning an annular plug between the blocking face and the prosthesis.

36. The method of claim 34 further comprising:

drilling a hole into the vertebral endplate.

37. The method of claim 34 wherein drilling a hole into the vertebral endplate includes bending a drilling shaft to drill a hole into the vertebral endplate.

38. The method of claim 34 wherein securing the retaining device to the vertebral endplate includes driving a fastener through the retaining device into the vertebral endplate.

39. The method of claim 34 further comprising:

deploying a selectively extendable stabilizer to engage a vertebral body.

40. A system for preventing migration of an intervertebral implant through an annular defect, the system comprising:

a first buttress plate for blocking migration of the intervertebral implant through the annular defect;

a fastener for attaching the first buttress plate to a vertebral endplate; and

an augmentation instrument including a bendable drive shaft, wherein the bendable drive shaft is adapted for driving the fastener through the first buttress plate and into the vertebral endplate.

41. The system of claim 40 further comprising:

a deformable annular plug for blocking the annular defect.

42. The system of claim 40 wherein the first buttress plate includes a blocking face for blocking the annular defect and a mounting face through which the fastener is driven.

43. The system of claim 40 wherein the blocking face is disposed generally perpendicular to the mounting face.

44. The system of claim 40 wherein the fastener is at least partially coated with hydroxyapetite.

45. The system of claim 44 wherein the mounting face includes a roughened surface texture.

46. The system of claim 44 wherein the mounting face is at least partially coated with hydroxyapetite.

47. The system of claim 40 wherein the first buttress plate includes a tapered portion adapted to extend between an annulus wall and the intervertebral implant.

48. The system of claim 40 further comprising a second buttress plate for blocking migration of the intervertebral implant through the annular defect.

49. The system of claim 48 wherein the first buttress plate overlaps the second buttress plate.