MULTIPIECE ALLOGRAFT IMPLANT

• US 20070208424A1
• Filed: 05/07/2007
• Published: 09/06/2007
• Est. Priority Date: 09/02/2003
• Status: Active Grant

• Current Assignee: Synthes USA LLC (Johnson & Johnson)
• Original Assignee: Synthes USA LLC (Johnson & Johnson)
• Inventors: Messerli, Dominique, Myer, Jacqueline, Angelucci, Christopher, Boyer, Michael
• Granted Patent: US 7,601,173 B2
• Time in Patent Office: Days
• US Class Current: 623/17.110
• 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 2002/30014 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2002/30032 differing in absorbability or resorbability, i.e. in absorption or resorption time
• CPC Class Codes: A61F 2002/30057 made from both cortical and cancellous adjacent parts
• CPC Class Codes: A61F 2002/30387 Dovetail connection
• CPC Class Codes: A61F 2002/30448 using adhesives
• CPC Class Codes: A61F 2002/30492 using a locking pin
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30843 Pyramidally-shaped
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/003 differing in adsorbability or resorbability, i.e. in adsorption or resorption time

Abstract

An allogenic implant for use in intervertebral fusion is formed from two parts. The first part, composed of cortical bone, provides mechanical strength to the implant, allowing the proper distance between the vertebrae being treated to be maintained. The second part, composed of cancellous bone, is ductile and promotes the growth of new bone between the vertebrae being treated and the implant, thus fusing the vertebrae to the implant and to each other. The implant is sized and shaped to conform to the space between the vertebrae. Teeth formed on the superior and inferior surfaces of the implant prevent short-term slippage of the implant.

Claims

1. An intervertebral implant for insertion between adjoining vertebra, said implant comprising:

a three dimensional body including a superior surface sized and configured for contacting at least a portion of one of said adjacent vertebrae, and an inferior surface sized and configured for contacting at least a portion of said other of said adjacent vertebrae;

said three dimensional body further comprising;

a first part formed of cortical bone and a second part formed of cancellous bone, wherein said first and second parts are connected to one another, and wherein at least one of said superior and inferior surfaces of said second part includes a first portion and a second portion, wherein said first portion includes a plurality of teeth and said second portion is substantially smooth, said teeth first portion of said second part defining a first surface area and said substantially smooth second portion of said second part defines a second surface area, said second surface area being greater than said first surface area.

2. The implant of claim 1, wherein said superior and inferior surfaces of said first part includes a plurality of teeth.

3. The implant of claim 2, wherein said superior and inferior surfaces of said first part comprises a surface area, said plurality of teeth formed on said first part covering a majority of said surface area of said first part.

4. The implant of claim 2, wherein said plurality of teeth formed on at least one of said superior and inferior surfaces of said first part are sized and configured to provide a mechanical interlock between said implant and said adjacent vertebra and said substantially smooth second portion of said second part is sized and configured to deform in order to conform to said adjacent vertebra.

5. The implant of claim 2, wherein both said superior and inferior surfaces of said second part includes a first portion and a second portion.

6. The implant of claim 5, wherein said substantially smooth superior and inferior surfaces of said second portion of said second part define an upper plane and a lower plane, respectively, said plurality of teeth formed on said superior and inferior surfaces of said first part having a tip portion, said tip portions being sized and configured to be at or below said upper and lower planes.

7. The implant of claim 1, further comprising a ledge formed on at least one of said superior and inferior surfaces of said second part, said ledge residing between said first and second portions.

8. The implant of claim 1, wherein said first and second parts are connected by at least one dovetail joint, wherein said dovetail joint includes a male portion and a female portion, said female portion being sized and configured to receive said male portion therein.

9. The implant of claim 8, wherein said male portion is on said first part and said female portion is on said second part.

10. The implant of claim 9, wherein said female portion of said second part has a first dimension and said male portion of said first part has a second dimension, said first dimension being smaller than said second dimension thus creating an interference fit between said male and female portions.

11. The implant of claim 8, wherein each of said first part and said second part includes at least one hole extending partially therethrough for receiving at least one pin to prevent said first part from moving with respect to said second part.

12. The implant of claim 11, wherein at least one of said holes passes through said male and female portions of said dovetail joint so that at least one of said pin passes through said dovetail joint to secure said first and second parts to one another.

13. The implant of claim 11, wherein said pin has a first diameter and said at least one hole has a second diameter, said first diameter being larger than said second diameter so that an interference fit is created between said at least one pin and said at least one hole.

14. The implant of claim 11, further comprising a first adhesive for securing said at least one pin to said at least one hole.

15. The implant of claim 14, further comprising a second adhesive for securing said first part to second part.

16. The implant of claim 1, wherein each of said first part and said second part includes at least one hole extending partially therethrough for receiving at least one pin to prevent said first part from moving with respect to said second part.

17. The implant of claim 16, wherein said first and second parts are connected by at least one dovetail joint, wherein said dovetail joint includes a male portion and a female portion, said female portion being sized and configured to receive said male portion therein and wherein at least one of said holes passes through said male and female portions of said dovetail joint so that at least one of said pin passes through said dovetail joint to secure said first and second parts to one another.

18. The implant of claim 2, wherein said three dimensional body further includes a posterior end, an anterior end, and first and second side surfaces sized and configured to extend between said anterior end to said posterior end, wherein said first and second side surfaces of said first part are substantially parallel with respect to one another and wherein said first and second side surfaces of said second portion of said second part are angled in towards said posterior end at an angle.

19. An intervertebral implant for insertion between adjoining vertebra, said implant comprising:

a three dimensional body including a superior surface sized and configured for contacting at least a portion of one of said adjacent vertebrae, and an inferior surface sized and configured for contacting at least a portion of said other of said adjacent vertebrae;

said three dimensional body further comprising;

a first part formed of cortical bone and a second part formed of cancellous bone, said superior and inferior surfaces of said second part includes a first portion and a second portion, wherein said superior and inferior surfaces of said first part and said superior and inferior surfaces of said first portion of said second part include a plurality of teeth and said second portion of said second part is substantially smooth; and

wherein said first and second parts are connected to one another by at least one dovetail joint, wherein said dovetail joint includes a male portion and a female portion, said female portion being sized and configured to receive said male portion, each of said first part and said second parts further comprising at least one hole extending partially therethrough for receiving at least one pin to prevent said first part from moving with respect to said second part;

at least one of said holes passes through said male and female portions of said dovetail joint.

20. The implant of claim 19, wherein said tooth portion of said second part defines a first surface area and said substantially smooth second portion of said second part defines a second surface area, said second surface area being greater than said first surface area.

21. The implant of claim 19, wherein said male portion of said dovetail joint is said first part and said female portion of said dovetail joint is said second part.

22. The implant of claim 19, wherein said plurality of teeth formed on said superior and inferior surfaces of said first part are sized and configured to provide a mechanical interlock between said implant and said adjacent vertebra and said substantially smooth portions formed on said superior and inferior surfaces of said second portion of said second part are sized and configured to deform in order to conform to said adjacent vertebra.

23. The implant of claim 19, wherein said substantially smooth superior and inferior surfaces of said second portion define an upper plane and a lower plane, respectively, said plurality of teeth formed on said superior and inferior surfaces of said first part having a tip portion, said tip portions being sized and configured to be at or below said upper and lower planes.

24. The implant of claim 19, further comprising a ledge formed on at least one of said superior and inferior surfaces of said second part, said ledge residing between said first and second portions.

25. The implant of claim 19, wherein said three dimensional body further includes a posterior end, an anterior end, and first and second side surfaces sized and configured to extend between said anterior end to said posterior end, wherein said first and second side surfaces of said first part are substantially parallel with respect to one another and wherein said first and second side surfaces of said second portion of said second part are angled in towards said posterior end at an angle.

26. An intervertebral implant for insertion between adjoining vertebra, said implant comprising:

a three dimensional body including a superior surface sized and configured for contacting at least a portion of one of said adjacent vertebrae, and an inferior surface sized and configured for contacting at least a portion of said other of said adjacent vertebrae;

said three dimensional body further comprising;

a first part formed of cortical bone and a second part formed of cancellous bone, wherein said first part is connected to said second part and wherein said superior and inferior surfaces of said second part includes a first portion and a second portion, wherein said superior and inferior surfaces of said first part and said superior and inferior surfaces of said first portion of said second part include a plurality of teeth and said second portion of said second part is substantially smooth; and

wherein said substantially smooth superior and inferior surfaces of said second portion of said second part define an upper plane and a lower plane, respectively, said plurality of teeth formed on said superior and inferior surfaces of said first part having a tip portion, said tip portion being sized and configured to be at or below said upper and lower planes.

27. The implant of claim 26, wherein said tooth portion of said second part defines a first surface area and said substantially smooth second portion of said second part defines a second surface area, said second surface area being greater than said first surface area.

28. The implant of claim 26, wherein said first and second parts are connected by at least one dovetail joint, wherein said dovetail joint includes a male portion and a female portion, said female portion being sized and configured to receive said male portion therein.

29. The implant of claim 28, wherein said male portion of said dovetail joint is on said first part and said female portion of said dovetail joint is on said second part.

30. The implant of claim 26, wherein each of said first part and said second part includes at least one hole extending partially therethrough for receiving at least one pin to prevent said first part from moving with respect to said second part.

31. The implant of claim 26, wherein said first and second parts are connected to one another by at least one dovetail joint, wherein said at least one dovetail joint includes a male portion and a female portion, said female portion being sized and configured to receive said male portion, each of said first part and said second parts further comprising at least one hole extending partially therethrough for receiving at least one pin to prevent said first part from moving with respect to said second part;

at least one of said holes passes through said male and female portions of said dovetail joint.

32. The implant of claim 26, wherein said plurality of teeth formed on said superior and inferior surfaces of said first part are sized and configured to provide a mechanical interlock between said implant and said adjacent vertebra and said substantially smooth portions formed on said superior and inferior surfaces of said second portion of said second part are sized and configured to deform in order to conform to said adjacent vertebra.

33. The implant of claim 26, further comprising a ledge formed on at least one of said superior and inferior surfaces of said second part, said ledge residing between said first and second portions.

34. The implant of claim 26, wherein said three dimensional body further includes a posterior end, an anterior end, and first and second side surfaces sized and configured to extend between said anterior end to said posterior end, wherein said first and second side surfaces of said first part are substantially parallel with respect to one another, and wherein said first and second side surfaces of said second portion of said second part are angled in towards said posterior end at an angle.