Apparatus for inserting spinal implants

• US 5,797,909 A
• Filed: 06/07/1995
• Issued: 08/25/1998
• Est. Priority Date: 06/13/1988
• Status: Expired due to Term

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: Gary K. Michelson
• Inventors: Michelson, Gary Karlin
• Primary Examiner(s): Brown, Michael A.
• Application Number:
  US08/482,215
• Time in Patent Office: 1,175 Days
• Field of Search: 606/60, 606/61, 606/72-79, 623/16, 623/17
• US Class Current: 606/914
• CPC Class Codes: A61B 17/025 Joint distractors
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 17/32 Surgical cutting instruments A61B18/042 takes precedence; suture cutters A61B17/0467; instruments for ligaturing or cutting A61B17/128; instruments for rupturing the amniotic membrane A61B17/4208; specially adapted knives for eye surgery A61F9/0133
• 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 17/8888 at its central region
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61B 2017/922 Devices for impaction, impact element
• CPC Class Codes: A61B 2090/036 abutting on tissue or skin
• CPC Class Codes: A61F 2/30744 End caps, e.g. for closing an endoprosthetic cavity
• 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 2/446 having a circular or elliptical cross-section substantially parallel to the axis of the spine, e.g. cylinders or frustocones
• CPC Class Codes: A61F 2/4603 for insertion or extraction of endoprosthetic joints or of accessories thereof
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/30143 hexagonal
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30235 tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30426 Bayonet coupling
• CPC Class Codes: A61F 2002/30593 : hollow
• CPC Class Codes: A61F 2002/30774 : internally-threaded
• CPC Class Codes: A61F 2002/30785 : parallel
• CPC Class Codes: A61F 2002/30787 : inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/30797 : internally-threaded
• CPC Class Codes: A61F 2002/30836 : knurled
• CPC Class Codes: A61F 2002/3085 : with a threaded, e.g. self-tapping, bone-engaging surface, e.g. external surface
• CPC Class Codes: A61F 2002/30904 : 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 2002/4619 : for extraction
• 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 2002/4629 : connected to the endoprosthesis or implant via a threaded connection
• CPC Class Codes: A61F 2002/4649 : Bone graft or bone dowel harvest sites
• CPC Class Codes: A61F 2002/4681 : by applying mechanical shocks, e.g. by hammering
• CPC Class Codes: A61F 2002/4687 : Mechanical guides for implantation instruments
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2230/0017 : Angular shapes
• CPC Class Codes: A61F 2230/0069 : cylindrical

Abstract

Apparatus and a method of inserting spinal implants is disclosed in which an intervertebral space is first distracted, a hollow sleeve having teeth at one end is then driven into the vertebrae adjacent that disc space. A drill is then passed through the hollow sleeve removing disc and bone in preparation for receiving the spinal implant which is then inserted through the sleeve. Apparatus and a method of inserting spinal implants is disclosed in which an intervertebral space is first distracted to restore the normal angular relationship of the vertebrae adjacent to that disc space. An extended outer sleeve having extended portions capable of maintaining the vertebrae distracted in their normal angular relationship is then driven into the vertebrae adjacent that disc space. A drill is then passed through the hollow sleeve removing disc and bone in preparation for receiving the spinal implant which is then inserted through the sleeve.

Claims

1. A spinal distractor for use in spinal fusion surgery for positioning two adjacent vertebrae in selected relationship to each other, said spinal distractor comprising:

a body; and

a disc penetrating extension extending from said body for insertion into the disc space between the two adjacent vertebrae and for bearing against adjacent endplates of the two adjacent vertebrae, said disc penetrating extension having a first portion for bearing against one of the adjacent endplates and a second portion for bearing against the other of the adjacent endplates, said first and second portions converging away from said body along at least a portion of their length.

2. The spinal distractor of claim 1 further comprising means for limiting the penetration of said disc penetrating extension into the disc space.

3. The spinal distractor of claim 2 in which said limiting means comprises a shoulder on said body at the juncture of said disc penetrating extension and said body for preventing said body from entering the disc space.

4. The spinal distractor of claim 1 in which said disc penetrating extension has a tapered front end to facilitate insertion of said disc penetrating extension into the disc space.

5. The spinal distractor of claim 1 in which said body is removably attached to said disc penetrating extension.

6. The spinal distractor of claim 5 further comprising means for limiting the depth of insertion of said disc penetrating extension into the disc space.

7. The spinal distractor of claim 6 in which said limiting means comprises a head associated with said disc penetrating extension, said head being dimensioned to prevent entry into the disc space.

8. The spinal distractor of claims 7 in which said head has a low profile so as to minimize protrusion of said head from the two adjacent vertebrae.

9. The spinal distractor of claim 6 further comprising an impacting surface at the juncture of said head and said disc penetrating extension for flattening portions of the exterior surface of the two adjacent vertebrae.

10. The spinal distractor of claim 6 in which said disc penetrating extension comprises means for engaging an extraction device for extracting said disc penetrating extension from the disc space.

11. The spinal distractor of claim 5 in which said disc penetrating extension includes a head proximate the juncture of said disc penetrating extension and said body.

12. The spinal distractor of claim 5 further comprising means for engaging the two adjacent vertebrae.

13. The spinal distractor of claim 12 in which said engaging means includes a prong.

14. The spinal distractor of claim 5 in which said disc penetrating extension comprises means for engaging an extraction device for extracting said disc penetrating extension from the disc space.

15. The spinal distractor of claim 1 in which said body is a barrel member.

16. The spinal distractor of claim 1 in which said disc penetrating extension has surface irregularities.

17. The spinal distractor of claim 16 in which said surface irregularities include ratchetings.

18. The spinal distractor of claim 16 in which said surface irregularities include knurling.

19. The spinal distractor of claim 1 in which said body has means for engaging an extraction device for extracting said disc penetrating extension from the disc space.

20. The spinal distractor of claims 19 in which said engaging means includes a mating member for mating with an extraction device.

21. The spinal distractor of claim 1 further comprising an impacting surface proximate the juncture of said body and said disc penetrating extension for flattening portions of the exterior surface of the two adjacent vertebrae.

22. The spinal distractor of claim 1 in combination with a guard member having an opening for providing protected access to the disc space and the adjacent vertebrae, said spinal distractor passing through said opening.

23. A spinal distractor for use in spinal fusion surgery for positioning two adjacent vertebrae in selected relationship to each other, said spinal distractor comprising:

a body; and

a disc penetrating extension extending from said body for insertion into the disc space between the two adjacent vertebrae and for bearing against adjacent endplates of the two adjacent vertebrae, said disc penetrating extension having a first portion for bearing against one of the adjacent endplates and a second portion for bearing against the other of the adjacent endplates, said first and second portions diverging away from said body along at least a portion of their length, said disc penetrating extension having a tapered leading end to facilitate placement of said disc penetrating extension into the disc space.

24. The spinal distractor of claim 23 further comprising means for limiting the penetration of said disc penetrating extension into the disc space.

25. The spinal distractor of claim 23 in which said limiting means comprises a shoulder on said body at the juncture of said disc penetrating extension and said body for preventing said body from entering the disc space.

26. The spinal distractor of claim 23 in which said body is removably attached to said disc penetrating extension.

27. The spinal distractor of claim 26 in which said disc penetrating extension includes a head proximate the juncture of said disc penetrating extension and said body.

28. The spinal distractor of claim 26 further comprising means for engaging the two adjacent vertebrae.

29. The spinal distractor of claim 28 in which said engaging means includes a prong.

30. The spinal distractor of claim 26 further comprising means for limiting the depth of insertion of said disc penetrating extension into the disc space.

31. The spinal distractor of claim 30 in which said limiting means comprises a head associated with said disc penetrating extension, said head being dimensioned to prevent entry into the disc space.

32. The spinal distractor of claims 31 in which said head has a low profile so as to minimize protrusion of said head from the two adjacent vertebrae.

33. The spinal distractor of claim 30 further comprising an impacting surface at the juncture of said head and said disc penetrating extension for flattening portions of the exterior surface of the two adjacent vertebrae.

34. The spinal distractor of claim 26 in which said disc penetrating extension comprises means for engaging an extraction device for extracting said disc penetrating extension from the disc space.

35. The spinal distractor of claim 30 in which said disc penetrating extension comprises means for engaging an extraction device for extracting said disc penetrating extension from the disc space.

36. The spinal distractor of claim 23 in which said body is a barrel member.

37. The spinal distractor of claim 23 in which said disc penetrating extension has surface irregularities.

38. The spinal distractor of claim 37 in which said surface irregularities include ratchetings.

39. The spinal distractor of claim 37 in which said surface irregularities include knurling.

40. The spinal distractor of claim 23 in which said body has means for engaging an extraction device for extracting said disc penetrating extension from the disc space.

41. The spinal distractor of claims 40 in which said engaging means includes a mating member for mating with an extraction device.

42. The spinal distractor of claim 23 further comprising an impacting surface proximate the juncture of said body and said disc penetrating extension for flattening portions of the exterior surface of the two adjacent vertebrae.

43. The spinal distractor of claim 23 in which said first and second portions diverge away from said body along at least a portion of their length.

44. The spinal distractor of claim 23 in combination with a guard member having an opening for providing protected access to the disc space and the adjacent vertebrae, said spinal distractor passing through said opening.

45. A surgical instrument set for use in spinal fusion surgery for positioning two adjacent vertebrae in selected relationship to each other, said surgical instrument set comprising:

a spinal distractor having a body and a disc penetrating extension extending from said body for insertion into the disc space between the two adjacent vertebrae and for bearing against adjacent endplates of the two adjacent vertebrae, said disc penetrating extension having a first portion for bearing against one of the adjacent endplates and a second portion for bearing against the other of the adjacent endplates, said first and second portions converging away from said body along at least a portion of their length;

a guard member having an opening for providing protected access to the disc space and the adjacent vertebrae, said opening being sized to permit passage of said disc penetrating extension of said spinal distractor through said opening; and

an implant driver having means for engaging an implant, said implant driver having a portion sized for passage through said opening for passing an implant through said guard member.

46. The surgical instrument set of claim 45 further comprising bone removal means having a portion sized for passage through said opening for forming through said guard member an implantation space across the disc space.

47. A surgical instrument set for use in spinal fusion surgery for positioning two adjacent vertebrae in selected relationship to each other, said surgical instrument set comprising:

a spinal distractor having a body and a disc penetrating extension extending from said body for insertion into the disc space between the two adjacent vertebrae and for bearing against adjacent endplates of the two adjacent vertebrae, said disc penetrating extension having a first portion for bearing against one of the adjacent endplates and a second portion for bearing against the other of the adjacent endplates, said first and second portions diverging away from said body along at least a portion of their length, said disc penetrating extension having a tapered leading end to facilitate placement of said disc penetrating extension into the disc space;

a guard member having an opening for providing protected access to the disc space and the adjacent vertebrae, said opening being sized to permit passage of said disc penetrating extension of said spinal distractor through said opening; and

an implant driver having means for engaging an implant, said implant driver having a portion sized for passage through said opening for passing an implant through said guard member.

48. The surgical instrument set of claim 47 further comprising bone removal means having a portion sized for passage through said opening for forming through said guard member an implantation space across the disc space.