ALLOGRAFT INTERVERTEBRAL IMPLANT AND METHOD OF MANUFACTURING THE SAME

• US 20080082173A1
• Filed: 09/12/2007
• Published: 04/03/2008
• Est. Priority Date: 09/13/2006
• Status: Active Grant

• Current Assignee: Synthes USA LLC (Johnson & Johnson)
• Original Assignee: Synthes USA LLC (Johnson & Johnson)
• Inventors: Walsh, Ryan, McManus, Joshua, Delurio, Robert
• Granted Patent: US 8,128,700 B2
• Time in Patent Office: Days
• US Class Current: 623/17.16
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/4465 having a circular or kidney shaped cross-section substantially perpendicular to the axis of the spine
• CPC Class Codes: A61F 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2/4644 Preparation of bone graft, bone plugs or bone dowels, e.g. grinding or milling bone material bone material A61F2/28; disintegrating or milling devices B02C
• 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 2002/30133 kidney-shaped or bean-shaped
• CPC Class Codes: A61F 2002/30387 Dovetail connection
• CPC Class Codes: A61F 2002/30492 using a locking pin
• 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 2002/4629 connected to the endoprosthesis or implant via a threaded connection
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2230/0015 Kidney-shaped, e.g. bean-shaped
• CPC Class Codes: A61F 2310/00359 Bone or bony tissue
• CPC Class Codes: Y10T 29/4998 Combined manufacture including applying or shaping of fluent material

Abstract

The present invention is directed to an allograft intervertebral implant sized and configured for insertion between adjacent vertebral bodies in a spinal fusion surgery. The implant is preferably manufactured from two or more pieces of allograft bone joined together by a joint, more preferably a dovetail joint. The dovetail joint being sized and configured to substantially follow the exterior shape or surface (e.g. perimeter) of the intervertebral implant. The intervertebral implant may also include one or more bone pins for joining the allograft pieces, the pins being inserted into the implant at an angle substantially perpendicular with respect to the dovetail joint. The intervertebral implant may also include one or more through-bores for receiving ostegenic or bone graft material. The intervertebral implant is preferably sized and configured for insertion during a T-PLIF or PLIF procedure.

Claims

1. An allograft intervertebral implant sized and configured for implantation between first and second adjacent vertebra via a transforaminal lumbar interbody fusion technique, the implant comprising:

an allograft body formed from at least two pieces of allograft bone, the body including a curved front surface, a curved back surface, a pair of ends separating the curved front and back surfaces, an upper surface and a lower surface wherein the upper and lower surfaces are sized and configured for contacting at least a portion of the first and second vertebrae, the curved front and back surfaces defining an outer perimeter of the implant;

wherein the at least two pieces of allograft bone are joined together by a dovetail joint, the dovetail joint having a curved shape that substantially follows the contours of the curved front and back surfaces of the body.

2. The allograft implant of claim 1, wherein the curved shape of the dovetail joint substantially follows the contours of the curved front and back surfaces and one of the end surfaces of the body, the other end surface of the body have an entry space for slidably receiving the dovetail joint.

3. The allograft implant of claim 1, wherein the at least two pieces of allograft bone each include a hole at least partially formed therein, the hole being sized and configured to receive at least one pin for further securing the pieces of allograft together.

4. The allograft implant of claim 3, wherein the at least one pin is substantially perpendicular with respect to the dovetail joint.

5. The allograft implant of claim 3, further comprising at least one vertical through-bore extending from the upper surface to the lower surface, the vertical through-bore being sized and configured to receive bone graft material.

6. An allograft intervertebral implant sized and configured for implantation between first and second adjacent vertebra via a transforaminal lumbar interbody fusion technique, the implant comprising:

an allograft body formed from at least two pieces of allograft bone, the body including a curved front surface, a curved back surface, a pair of ends separating the curved front and back surfaces, an upper surface and a lower surface wherein the upper and lower surfaces are sized and configured for contacting at least a portion of the first and second vertebrae, the curved front and back surfaces defining an outer perimeter of the implant, at least one vertical through-bore extending from the upper surface to the lower surface, the vertical through-bore being sized and configured to receive bone graft material;

wherein the at least two pieces of allograft bone are joined together by a dovetail joint, the dovetail joint having a curved shape that substantially follows the contours of the curved front and back surfaces of the body.

7. The allograft implant of claim 6, wherein the at least two pieces of allograft bone each include at least one hole at least partially formed therein, the hole being sized and configured to receive at least one pin for further securing the pieces of allograft together.

8. The allograft implant of claim 7, wherein each of the ends contains at least one for hole formed therein for receiving one of the pins.

9. The allograft implant of claim 7, wherein each of the holes is substantially perpendicular with respect to the dovetail joint.

10. An allograft intervertebral implant sized and configured for implantation between first and second adjacent vertebra via a transforaminal lumbar interbody fusion technique, the implant comprising:

an allograft body formed from at least two pieces of allograft bone, the body including a curved front surface, a curved back surface, a pair of ends separating the curved front and back surfaces, an upper surface and a lower surface wherein the upper and lower surfaces are sized and configured for contacting at least a portion of the first and second vertebrae, the curved front and back surfaces defining an outer perimeter of the implant, at least one vertical through-bore extending from the upper surface to the lower surface, the vertical through-bore being sized and configured to receive bone graft material, and at least one substantially vertical hole at least partially formed in each of the at least two pieces of allograft bone, the hole being sized and configured to receive at least one pin for further securing the pieces of allograft bone together;

wherein the at least two pieces of allograft bone are joined together by a dovetail joint, the dovetail joint having a curved shape that substantially follows the contours of the curved front and back surfaces of the body.

11. The allograft implant of claim 10, wherein the upper and lower surfaces include a plurality of teeth formed thereon.

12. The allograft implant of claim 10, further comprising at least one non-threaded, horizontal channel configured and adapted for engagement by an implant insertion tool, the channel being disposed along at least a portion of one of the curved front or back surfaces.

13. The allograft implant of claim 10, wherein each of the holes is substantially perpendicular with respect to the dovetail joint.

14. An allograft intervertebral implant sized and configured for implantation between first and second adjacent vertebra via a posterior lumbar interbody fusion procedure, the implant comprising:

an allograft body formed from at least two pieces of allograft bone, the body including an anterior surface, a posterior surface, a pair of lateral side surfaces, an upper surface and a lower surface wherein the upper and lower surfaces are sized and configured for contacting at least a portion of the first and second vertebrae;

wherein the at least two pieces of allograft bone are joined together by at least one dovetail joint, the at least one dovetail joint being orientated substantially transverse to a longitudinal axis of the body.

15. The allograft implant of 14, wherein the allograft body further includes at least one vertical through-bore extending from the upper surface to the lower surface, the vertical through-bore being sized and configured to receive bone graft material.

16. The allograft implant of 15, wherein the pieces of allograft bone each include at least one hole at least partially formed therein, the hole being sized and configured to receive at least one pin for further securing the pieces of allograft together.

17. The implant of claim 16, wherein the at least one pin is substantially vertical with respect to the dovetail joint.

18. A method for manufacturing an allograft implant from two or more individual pieces, the method comprising the following steps:

a) obtaining one or more pieces of allograft bone;

b) shaping the individual implant pieces out of allograft bone into their desired shaped, the desired shape including forming one or more of the recesses or projections of a dovetail joint;

c) removing the individual implant pieces from the allograft bone; and

d) joining the individual pieces together by sliding the individual members together via the dovetail joint.

19. The method of claim 18, further including the step of forming one or more holes into the individual pieces, the holes being sized and configured to receive bone pins.

20. The method of claim 18, further including the step of forming one or more vertical through-bores into the implant, the vertical through-bore being sized and configured to receive bone graft material.

21. The method of claim 20, wherein the step of forming the vertical through-bore occurs after the individual pieces have been joined together.