Bone blocks and methods for inserting bone blocks into intervertebral spaces

• US 6,368,325 B1
• Filed: 05/26/1999
• Issued: 04/09/2002
• Est. Priority Date: 05/27/1998
• Status: Expired due to Fees

• Current Assignee: Nuvasive Incorporated
• Original Assignee: Nuvasive Incorporated
• Inventors: Marino, James F., Stone, Corbett W., McKinley, James T.
• Primary Examiner(s): Smith, Jeffrey A.
• Assistant Examiner(s): Priddy, Michael B.
• Application Number:
  US09/320,081
• Time in Patent Office: 1,049 Days
• Field of Search: 623/17.11, 623/16.11, 623/11.11, 606/53, 606/90, 606/97
• US Class Current: 606/99
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/30179 X-shaped
• 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 2002/30383 made by laterally inserting a protrusion, e.g. a rib into a complementarily-shaped groove
• CPC Class Codes: A61F 2002/30492 using a locking pin
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• 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 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 2230/0058 X-shaped
• CPC Class Codes: A61F 2310/00359 Bone or bony tissue

Abstract

A method for inserting a bone block into a patient'"'"'s intervertebral space, comprising: supporting the bone block in an inserter; advancing the inserter into the intervertebral space; rotating the inserter, thereby separating adjacent vertebrae; separating the bone block and the inserter with a push rod; and removing the inserter from the intervertebral space.

Claims

1. A method for inserting a bone block into a patient'"'"'s intervertebral space, comprising:

supporting the bone block in an inserter;

advancing the inserter into the intervertebral space;

rotating the inserter by 90°

, thereby separating the adjacent vertebrae by camming action; and

removing the inserter from the intervertebral space.

2. The method of claim 1, wherein rotating the inserter, thereby separating the adjacent vertebrae by camming action, comprises:

engaging convexly curved camming surfaces on the inserter against the adjacent vertebrae.

3. The method of claim 1, wherein advancing the inserter into the intervertebral space comprises:

advancing the inserter through a cannula which has been percutaneously introduced into the patient.

4. The method of claim 3, wherein,

the cannula is introduced in a posterolateral approach.

5. The method of claim 3, wherein,

the cannula has an oval or racetrack-shaped cross section, the cross section being defined by an ellipse having a major dimension and a minor dimension.

6. The method of claim 3, wherein,

the cannula has an oval or racetrack-shaped cross section, the cross section being defined by an ellipse having a major dimension and a minor dimension.

7. The method of claim 6, wherein,

the cannula is disposed with the major dimension of the ellipse parallel to the adjacent vertebrae;

and

the inserter has a cross section defined by a major dimension and a minor dimension, wherein rotation of the inserter causes the major dimension of the inserter to be disposed perpendicular to the adjacent vertebrae.

8. The method of claim 7, wherein removing the inserter from the intervertebral space comprises:

removing separate sections of the inserter through the cannula when the major dimension of the cross section of the inserter is perpendicular to the major dimension of the cross section of the cannula.

9. The method of claim 1, wherein the inserter has a central longitudinally extending axis, and wherein rotating the inserter comprises:

rotating the inserter about a central longitudinal axis passing therethrough.

10. The method of claim 1, wherein removing the inserter comprises:

withdrawing the inserter while simultaneously holding the bone block in a stationary position with a push rod, the push rod being slidably received in a longitudinally extending bore in the inserter.

11. The method of claim 10, wherein the push rod and the bone block are threadably interconnected, with the push rod being received into a threaded bore in the bone block, further comprising:

rotating the push rod to unscrew the push rod from the bone block, thereby disconnecting the push rod from the bone block.

12. The method of claim 1, wherein removing the inserter comprises:

rotating the bone block to an anchored position such that vertebral support surfaces on the bone block engage the adjacent vertebrae, holding the bone block in position and slidably withdrawing the inserter from the bone block.

13. The method of claim 1, wherein removing the inserter from the intervertebral space comprises:

removing the inserter in sections, with each of the sections extending the longitudinal length of the inserter.

14. The method of claim 13, wherein,

the sections comprise two opposite halves of the inserter.

15. A system for introducing a bone block into the intervertebral space of a patient, comprising:

a rotatable inserter having two prongs at a distal end, the distal end of the inserter having an oval-shaped cross section; and

a bone block received between the two prongs.

16. The system of claim 15, wherein, each prong has an outer convexly curved camming surface.

17. The system of claim 15, wherein,

the two prongs are disposed on opposite sides of the bone block, with each prong having a longitudinally extending groove on an inner surface adjacent the bone block.

18. The system of claim 17, wherein,

the bone block has lateral protrusions which extend longitudinally along the length of the bone block;

and

wherein the lateral protrusions on the bone block are dimensioned to mate with the longitudinally extending grooves on the inner surfaces of the prongs such that the bone block can slide longitudinally between the prongs.

19. The system of claim 18, wherein,

the inserter comprises a first half and a second half which are separable from one another such that the first and second halves can be separately withdrawn through the cannula.

20. The system of claim 15, further comprising:

a cannula dimensioned to receive the inserter therein.

21. The system of claim 15, wherein,

the cannula has an oval or racetrack-shaped cross section, the cross section being defined by an ellipse having a major dimension and a minor dimension.

22. The system of claim 15, wherein,

the bone block has at least one anchoring fin.

23. The system of claim 15, wherein,

the bone block is cannulated along its length.

24. The system of claim 23, further comprising:

a fastening pin dimensioned to be received in the cannulation in the bone block.

25. The system of claim 15, further comprising:

a second bone block, wherein the second bone block is adapted to interlock with the bone block.

26. A system for introducing a bone block into the intervertebral space of a patient, comprising:

an rotatable inserter having two prongs at a distal end; and

a bone block received between the two prongs, wherein the two prongs are disposed on opposite sides of the bone block, with each prong having a longitudinally extending groove on an inner surface adjacent the bone block.

27. A system for introducing a bone block into the intervertebral space of a patient, comprising:

an rotatable inserter having two prongs at a distal end, each prong having an outer convexly curved camming surface and a longitudinally extending groove disposed on an inner surface; and

a bone block received between the two prongs, the bone block having lateral protrusions which are dimensioned to mate with the longitudinally extending grooves on the inner surfaces of the prongs such that the bone block can slide longitudinally between the prongs.