Spinal fixation plates and plate extensions

• US 20050240185A1
• Filed: 04/23/2004
• Published: 10/27/2005
• Est. Priority Date: 04/23/2004
• Status: Active Grant

• Current Assignee: Depuy Spine Sarl (Johnson & Johnson)
• Original Assignee: Depuy Spine Sarl (Johnson & Johnson)
• Inventors: Murphy, Raymond F., Boomer, Mark C., Kalfas, Iain
• Granted Patent: US 7,572,282 B2
• Time in Patent Office: Days
• US Class Current: 606/277
• CPC Class Codes: A61B 17/7055 connected to sacrum, pelvis or skull
• CPC Class Codes: A61B 17/7059 Cortical plates A61B17/7007, A61B17/7058 take precedence
• CPC Class Codes: Y10S 606/902 Cortical plate specifically adapted for a particular bone

Abstract

A spinal fixation plate that is adapted to be implanted in a variety of positions in the occiput is provided. In general, the plate has a substantially planar configuration and it includes a mid-line or central portion having several thru-bores formed therein, and first and second opposed branch portions that extend from the central portion and that also include at least one thru-bore formed therein. The configuration of the branch portions relative to the central portion, as well as the position of the mid-line thru-bores formed in the central portion in relation to the thru-bore(s) formed in each branch portion, allow the spinal fixation plate to be implanted in a variety of positions in the occiput, thus allowing the optimal implant site to be selected.

Claims

1. An implantable spinal fixation plate, comprising:

an elongate central portion having proximal and distal ends that define a longitudinal axis extending therebetween, the central portion including a first thru-bore formed therein, and a second thru-bore formed therein and positioned distal of the first thru-bore; and

first and second elongate branch portions that extend from opposed sides of the central portion and that define first and second central axes that are positioned at an angle less than 90°

relative to the longitudinal axis of the central portion, the first and second central axes intersecting at an intersection point that is distal to a substantial midpoint of the first thru-bore formed in the central portion, and that is proximal to a substantial midpoint of the second thru-bore formed in the central portion.

2. The implantable spinal fixation plate of claim 1, wherein the intersection point is positioned distal to the first thru-bore and proximal to the second thru-bore.

3. The implantable spinal fixation plate of claim 1, wherein the first and second branch portions are positioned distal to the proximal end of the central portion.

4. The implantable spinal fixation plate of claim 1, wherein the intersection point intersects the longitudinal axis of the central portion.

5. The implantable spinal fixation plate of claim 1, further comprising at least one thru-bore formed in each of the first and second branch portions.

6. The implantable spinal fixation plate of claim 5, wherein at least one of the thru-bores in the first and second branch portions is adapted to mate to a spinal fixation element.

7. The implantable spinal fixation plate of claim 5, wherein at least one of the thru-bores in the first and second branch portions includes an anchoring feature formed thereon for receiving a spinal fixation element.

8. The implantable spinal fixation plate of claim 5, wherein each of the first and second branch portions includes at least one thru-bore formed therein adjacent to a terminal end thereof.

9. The implantable spinal fixation plate of claim 8, wherein at least one of the thru-bores in each of the first and second branch portions has an oblong shape.

10. The implantable spinal fixation plate of claim 8, wherein at least one of the thru-bores in each of the first and second branch portions has a circular shape.

11. The implantable spinal fixation plate of claim 10, wherein at least one of the thru-bores in each of the first and second branch portions includes a substantially cylindrical member extending therefrom.

12. The implantable spinal fixation plate of claim 11, wherein the substantially cylindrical member includes threads formed therein.

13. The implantable spinal fixation plate of claim 1, further comprising at least one thru-bore formed in the central portion and positioned distal of the second thru-bore.

14. The implantable spinal fixation plate of claim 1, wherein the central portion and the first and second branch portions extend along a horizontal plane, and wherein the plate further comprises a bend zone formed between each of the first and second branch portions and the central portion for allowing the first and second branch portions can bend out of the horizontal plane.

15. The implantable spinal fixation plate of claim 14, wherein each bend zone extends along an axis that is substantially parallel to the longitudinal axis of the central portion.

16. The implantable spinal fixation plate of claim 14, wherein each bend zone comprises at least one channel formed on a surface of the plate.

17. The implantable spinal fixation plate of claim 14, wherein each bend zone comprises opposed channels formed on opposed surfaces of the plate.

18. The implantable spinal fixation plate of claim 1, further comprising at least one elongate extension member removably matable to the spinal fixation plate and having a plurality of thru-bores formed therein.

19. The implantable spinal fixation plate of claim 18, wherein the at least one elongate extension member includes a clamp mechanism formed thereon for receiving and engaging a spinal fixation element.

20. The implantable spinal fixation plate of claim 1, further comprising an elongate extension member having a central thru-bore formed therein, and first and second thru-bores formed therein on opposed sides of the central thru-bore, the central thru-bore being adapted to receive a fastening element for removably mating the elongate extension member to the first thru-bore in the central portion of the spinal fixation plate.

21. The implantable spinal fixation plate of claim 1, further comprising an elongate extension member having a plurality of thru-bores formed therein, and having a dovetail component that is adapted to slidably mate with a complementary dovetail component formed on the plate.

22. The implantable spinal fixation plate of claim 20, wherein the first and second thru-bores are formed through opposed terminal ends of the elongate extension member, the opposed terminal ends extending in a plane that is substantially parallel to but spaced apart from a plane defined by a central portion of the extension member that contains the central thru-bore.

23. An implantable spinal fixation plate, comprising:

an elongate central portion having proximal and distal ends that define a longitudinal axis extending therebetween, the central portion including a first thru-bore formed therein, and a second thru-bore formed therein and positioned distal of the first thru-bore; and

first and second elongate branch portions that extend from opposed sides of the central portion at a position distal to the proximal end of the central portion and proximal to the distal end of the central portion, each branch portion including at least one thru-bore formed therein.

24. The implantable spinal fixation plate of claim 23, wherein the first and second branch portions define first and second central axes that are positioned at an angle relative to the longitudinal axis of the central portion, the first and second central axes intersecting at an intersection point that is distal to a substantial midpoint of the first thru-bore formed in the central portion, and that is proximal to a substantial midpoint of the second thru-bore formed in the central portion.

25. The implantable spinal fixation plate of claim 23, wherein each of the first and second branch portions includes at least one thru-bore formed therein adjacent a terminal end thereof.

26. The implantable spinal fixation plate of claim 25, wherein at least one of the thru-bores in each of the first and second branch portions has a shape selected from the group consisting of oblong and circular.

27. The implantable spinal fixation plate of claim 25, wherein at least one of the thru-bores in each of the first and second branch portions includes a barrel extending therefrom.

28. The implantable spinal fixation plate of claim 23, further comprising at least one thru-bore formed in the central portion and positioned distal of the second thru-bore.

29. The implantable spinal fixation plate of claim 23, further comprises at least one bend zone formed in the spinal fixation plate for allowing bendable movement of at least one of the first and second branch portions out of a horizontal plane in which the central portion lies.

30. The implantable spinal fixation plate of claim 29, wherein each bend zone comprises at least one channel formed on a surface of the plate.

31. The implantable spinal fixation plate of claim 23, further comprising at least one elongate extension member removably matable to the spinal fixation plate and having a plurality of thru-bores formed therein.

32. The implantable spinal fixation plate of claim 31, wherein the at least one elongate extension member includes a clamp mechanism formed thereon for receiving and engaging a spinal fixation element.

33. The implantable spinal fixation plate of claim 23, further comprising an elongate extension member having a central thru-bore formed therein, and first and second thru-bores formed on opposed sides of the central thru-bore, the central thru-bore being adapted to receive a fastening element for removably mating the elongate extension to the first thru-bore in the central portion of the spinal fixation plate.

34. The implantable spinal fixation plate of claim 33, wherein the first and second thru-bores are formed through opposed terminal ends of the elongate extension member, the opposed terminal ends extending in a plane that is substantially parallel to but spaced apart from a plane defined by a central portion of the extension member that contains the central thru-bore.

35. A spinal fixation kit, comprising:

a spinal fixation plate having at least one thru-bore formed therein; and

at least one extension plate having a plurality of thru-bores formed therein, at least one of the plurality of thru-bores in each extension plate being adapted to be aligned with at least one of the thru-bores formed in the spinal fixation plate to allow the extension plate to removably mate to the spinal fixation plate.

36. The spinal fixation kit of claim 35, wherein the spinal fixation plate is an occipital plate.

37. The spinal fixation kit of claim 36, wherein the spinal fixation plate includes an elongate central portion having a first and second thru-bores formed therein and positioned along a longitudinal axis thereof, and first and second elongate branch portions that extend from opposed sides of the central portion at a location that is substantially between the first and second thru-bores formed in the central portion, each branch portion including at least one thru-bore formed therein.

38. The spinal fixation kit of claim 37, wherein at least one of the plurality of thru-bores formed in the at least one extension plate is adapted to be juxtapositioned on at least one of the thru-bores formed in at least one of the first and second elongate branch portions and the central portion.

39. The spinal fixation kit of claim 38, wherein at least one extension plate has a generally elongate shape with a central thru-bore and first and second thru-bores formed on opposed sides of the central thru-bore, the central thru-bore being adapted to be juxtapositioned on the first thru-bore formed in the elongate central portion of the spinal fixation plate.

40. The spinal fixation kit of claim 39, further comprising a first bend formed in the extension plate between the central thru-bore and the first thru-bore, and a second bend formed in the extension plate between the central thru-bore and the second thru-bore.

41. The spinal fixation kit of claim 38, wherein the extension plate has a generally elongate shape and includes first and second thru-bores formed therein, the first thru-bore being configured to be juxtapositioned on a thru-bore formed on a terminal end of each of the first and second branch portions.

42. The spinal fixation kit of claim 41, further comprising a bend formed in the extension plate between the first and second thru-bores.

43. The spinal fixation kit of claim 41, further comprising a clamp member formed adjacent to the first screw bore and adapted to receive and engage a spinal fixation element.

44. The spinal fixation kit of claim 43, wherein the clamp member includes a pathway extending therethrough for seating a portion of a spinal fixation element, and a central aperture formed therein and juxtapositioned on the first thru-bore formed in the extension plate, and wherein the clamp member is adapted to engage a spinal fixation element seated within the pathway when a fastening element is disposed through the central aperture in the clamp member and through the thru-bore formed in the extension plate.

45. The spinal fixation kit of claim 35, further comprising a fastening element for mating the at least one extension plate to the spinal fixation plate.

46. The spinal fixation kit of claim 45, wherein the fastening element comprises a bone screw.

47. The spinal fixation kit of claim 35, wherein the at least one extension plate includes a mating element formed thereon for slidably mating with a complementary mating element formed on the spinal fixation plate.

48. The spinal fixation kit of claim 47, wherein the complementary mating elements comprises dovetail components.

49. A spinal fixation kit, comprising:

a spinal fixation plate having at least one thru-bore formed therein and a mating element formed thereon; and

at least one extension plate having a plurality of thru-bores formed therein and a complementary mating element formed thereon such that the at least one extension plate is slidably matable with the spinal fixation plate.

50. The spinal fixation kit of claim 49, wherein the mating elements comprise male and female dovetail components.

51. A spinal fixation plate, comprising:

a central portion with at least one thru-bore formed therein;

first and second branch members extending from the central portion; and

a chamfer formed around at least a portion of a perimeter of the central portion, the chamfer having a width that is greater than about half of a width of the portion of the central portion containing the chamfer.