Intervertebral implant

• US 8,764,831 B2
• Filed: 12/15/2010
• Issued: 07/01/2014
• Est. Priority Date: 02/06/2003
• Status: Expired due to Term

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: DePuy Synthes Products LLC (Johnson & Johnson)
• Inventors: Lechmann, Beat, Burkard, Dominique, Cain, Chris M. J., Mathieu, Claude
• Primary Examiner(s): Philogene, Pedro
• Assistant Examiner(s): Schneider, Lynnsy
• Application Number:
  US12/969,330
• Publication Number:
  US 20110087327A1
• Time in Patent Office: 1,294 Days
• Field of Search: 623 1711- 1716
• US Class Current: 623/17.12
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• 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 2/4455 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 2/4465 having a circular or kidney shaped cross-section substantially perpendicular to the axis of the spine
• 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 2002/30426 Bayonet coupling
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30517 using a locking plate
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30774 internally-threaded
• CPC Class Codes: A61F 2002/30777 Oblong apertures
• CPC Class Codes: A61F 2002/30843 Pyramidally-shaped
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys

Abstract

An intervertebral implant having a three-dimensional body and a securing plate. The intervertebral implant also includes a front plate (8) displaceably disposed as an insert with a front side of the three-dimensional body.

Claims

1. A bone stabilizing system configured to be inserted into an intervertebral space, the bone stabilizing system comprising:

(a) a plurality of bone screws each having a shaft and a head that is connected to the shaft, each of the shafts being elongate along a respective longitudinal central axis;

(b) an integral one-piece body defining a front body surface, a rear body surface opposite the front body surface, a left side surface, a right side surface opposite the left side surface along a lateral direction, a lower body surface, an upper body surface spaced from the lower body surface in a first direction, a portion of the one-piece body that is continuous along the lateral direction from the left side surface to the right side surface, and a recess that extends at least into the upper body surface such that the recess defines a body opening that is open to the first direction,

wherein the one-piece body is configured such that when the bone stabilizing system is inserted into the intervertebral space;

     1) the upper body surface contacts an endplate of a first vertebra; and

     2) the lower body surface contacts an endplate of a second vertebra;

(c) a front plate configured to be mounted to the one-piece body, the front plate comprising a biocompatible, non-bone material, the front plate defining a front plate surface, a rear plate surface opposite the front plate surface such that when the front plate is mounted to the one-piece body the rear plate surface faces the front body surface, the front plate further defining a plurality of screw holes each configured to receive one of the plurality of bone screws such that the shaft of the respective one of the plurality of bone screws passes through the endplate of the first vertebra or the endplate of the second vertebra,

wherein a first of the plurality of screw holes defines a first central axis that extends through a first opening and a second opening in the front plate such that the first central axis is at a first oblique angle relative to the rear plate surface, a second of the plurality of screw holes defines a second central axis that extends through a third opening and a fourth opening in the front plate such that the second central axis is at a second oblique angle relative to the rear plate surface, and when the front plate is mounted to the one-piece body;

     1) the first opening is positioned in the front plate surface between the left side surface and the right side surface with respect to the lateral direction;

     2) the third opening is positioned between the left side surface and the right side surface with respect to the lateral direction; and

     3) the front plate is devoid of screw holes with an opening that A) is positioned in the front plate surface and B) has a center that is positioned beyond the body opening with respect to the first direction.

2. The system of claim 1, wherein the body opening is a first body opening, the lower body surface is spaced from the upper body surface in a second direction, the lower body surface defines a second opening that faces the second direction, and the front plate is devoid of screw holes positioned beyond the second opening with respect to the second direction when the front plate is mounted to the one-piece body.

3. The system of claim 1, wherein the front plate defines an uppermost plate surface and an opposed lowermost plate surface, at least a portion of both the uppermost and lowermost plate surfaces are configured to be disposed within the intervertebral space when the front plate is mounted to the one-piece body and the one-piece body is disposed within the intervertebral space.

4. The system of claim 3, wherein an entirety of the uppermost plate surface is configured to be disposed between the endplates of the first and second vertebrae when the front plate is mounted to the one-piece body and the one-piece body is disposed between the endplates of the first and second vertebrae.

5. The system of claim 3, wherein each of the first and second oblique angles is from about 30°

to about 70°

.

6. The system of claim 5, wherein the front plate and at least one of the screw holes in the front plate are configured such that a first of the plurality of bone screws inserted into a respective one of the plurality of screw holes pierces either the upper body surface or the lower body surface when the front plate is mounted to the one-piece body.

7. The system of claim 6, wherein the front plate is configured such that the first of the plurality of bone screws pierces the upper body surface and a second of the plurality of bone screws inserted into a respective one of the plurality of screw holes pierces the lower body surface when the front plate is mounted to the one-piece body.

8. The system of claim 5, wherein the first central axis extends toward the upper body surface when the front plate is mounted to the one-piece body and the second central axis extends toward the lower body surface when the front plate is mounted to the one-piece body.

9. The system of claim 5, wherein the front plate is formed of a metallic material and the one-piece body is formed from a non-metallic material.

10. The system of claim 9, wherein the one-piece body is made from a plastic material.

11. The system of claim 5, wherein the front plate defines a maximum plate height from the uppermost plate surface to the lowermost plate surface and wherein the front body surface defines a maximum body height from the upper body surface to the lower body surface that is substantially equal to the maximum plate height.

12. The system of claim 5, wherein the front body surface defines a maximum body height from the upper body surface to the lower body surface, and the front plate defines a maximum plate height from the uppermost plate surface to the lowermost plate surface that is less than the maximum body height.

13. The system of claim 5, wherein the front plate defines a maximum plate height from the uppermost plate surface to the lowermost plate surface, and the one-piece body defines a maximum body height from the upper body surface to the lower body surface, wherein the maximum body height is substantially equal to or greater than the maximum plate height.

14. The system of claim 5, wherein the one-piece body further includes a first screw recess in communication with the front body surface and the upper body surface and a second screw recess in communication with the front body surface and the lower body surface, such that when the front plate is mounted to the one-piece body the first screw recess is aligned with one of the plurality of screw holes and the second screw recess is aligned with another of the plurality of screw holes.

15. The system of claim 5, wherein the recess is a throughhole that extends from the upper body surface to the lower body surface.

16. The system of claim 5, wherein at least one of the plurality of screw holes includes internal threads, and at least a portion of the head of one of the plurality of bone screws has a threaded portion that includes external threads configured to engage the internal threads of the one of the plurality of screw holes.

17. The system of claim 16, wherein the threaded portion is conically tapered.

18. The system of claim 5, further comprising a securing plate operatively connectable to the front plate in a manner to at least partially contain the head of at least one of the plurality of bone screws receivable in one of the plurality of screw holes between the front plate and the securing plate.

19. The system of claim 18, wherein the securing plate is fastenable to the front plate by at least one of a screw connection, a bayonet catch or a click catch.

20. The system of claim 5, further comprising a securing plate operatively connectable to the front plate in a manner to at least partially cover at least two of the plurality of screw holes.

21. A spine stabilizing system configured to be inserted into an intervertebral space, the spine stabilizing system comprising:

(a) a plurality of bone screws each having a shaft and a head that is connected to the shaft, each of the shafts being elongate along a respective longitudinal central axis;

(b) a one-piece body defining a front body surface, a rear body surface opposite the front body surface, a left side surface, a right side surface opposite the left side surface, a lower body surface, an upper body surface spaced from the lower body surface in a first direction, a recess that extends from a first opening in the upper body surface to a second opening in the lower body surface, and a body hole configured to receive one of the plurality of bone screws,

wherein the one-piece body is configured such that when the spine stabilizing system is inserted into the intervertebral space;

     1) the upper body surface faces an endplate of a first vertebra; and

     2) the lower body surface faces an endplate of a second vertebra; and

(c) a front plate defining an uppermost plate surface, a lowermost plate surface opposite the uppermost plate surface, a front plate surface, a rear plate surface opposite the front plate surface, the front plate configured to be mounted to the one-piece body such that, the rear plate surface faces the front body surface; and

     2) the first opening remains open to the first direction the front plate further defining a plurality of screw holes each configured to receive one of the plurality of bone screws such that the shaft of one of the plurality of bone screws passes through one of the plurality of screw holes, the body hole and one of the endplates of the first and second vertebrae, each of the plurality of screw holes defining a respective central axis, at least two of the plurality of screw holes extending through the front plate so that the central axis of each of the at least two of the plurality of screw holes is at an oblique angle relative to the rear plate surface, at least a portion of the uppermost plate surface configured to be disposed within the intervertebral space when the front plate is mounted to the one-piece body and the one-piece body is disposed within the intervertebral space,

wherein the front plate is devoid of screw holes with an opening that

     1) is positioned in the front plate surface and

     2) has a center that is positioned beyond the first opening with respect to the first direction when the front plate is mounted to the one-piece body.

22. The system of claim 21, further comprising a securing plate operatively connectable to the front plate in such a manner to at least partially cover at least one of the plurality of screw holes.

23. The system of claim 21, wherein at least one of the plurality of screw holes includes internal threads.

24. The system of claim 21, wherein at least one of the plurality of bone screws includes external threading at least partially on the head.

25. The system of claim 21, wherein the front plate defines a maximum plate height from the uppermost plate surface to the lowermost plate surface, the one-piece body defines a maximum body height from upper body surface to the lower body surface, and the maximum plate height is substantially equal to the maximum body height.

26. The system of claim 21, wherein the one-piece body defines a middle plane equidistantly spaced between the upper body surface and the lower body surface, and the front plate is mountable to the one-piece body such that the central axis of each of the at least two of the plurality of screw holes defines a respective angle ranging from about 20°

to about 60°

relative to the middle plane.

27. The system of claim 21, wherein the one-piece body defines a middle plane equidistantly spaced between the left and right side surfaces, the middle plane extends from the front surface to the rear surface, and the front plate is mountable to the one-piece body such that the respective longitudinal central axis of each of the plurality of bone screws inserted into one of the plurality of screw holes defines a respective angle ranging from about 10°

to about 45°

relative to the middle plane.

28. The system of claim 26, wherein the middle plane is a first middle plane, and the one-piece body defines a second middle plane equidistantly spaced between the left and right side surfaces, the second middle plane extends from the front plate surface to the rear body surface, and the front plate is mountable to the one-piece body such that the respective longitudinal central axis of each of the plurality of bone screws defines a respective angle ranging from about 10°

to about 45°

relative to the second middle plane.

29. The system of claim 21, wherein the oblique angle between the axis of each of the at least two of the plurality of screw holes and the rear plate surface of the front plate is from about 30°

to about 70°

.

30. The system of claim 21, wherein an entirety of the uppermost plate surface is configured to be disposed within the intervertebral space when the front plate is mounted to the one-piece body and the one-piece body is disposed within the intervertebral space.

31. The system of claim 21, wherein the one-piece body is at least partially formed of plastic, the front plate is at least partially formed of a metallic material, and the at least two of the plurality of screw holes include a first angled screw hole and a second angled screw hole, the first angled screw hole angled in the front plate toward the uppermost plate surface, and the second angled screw hole angled in the front plate toward the lowermost plate surface.

32. The system of claim 21, wherein the lower body surface is spaced from the upper body surface in a second direction, and the one-piece body and the front plate are both devoid of screw holes positioned beyond the second opening with respect to the second direction.

33. The system of claim 21, wherein the front plate comprises a biocompatible, non-bone material.

34. The system of claim 21, wherein the first opening includes an outer perimeter that is defined entirely by the upper body surface.

35. A spine stabilizing system configured to be inserted into an intervertebral space, the spine stabilizing system comprising:

a plurality of bone screws each having a shaft and a head that is connected to the shaft, each of the shafts being elongate along a respective longitudinal central axis;

a one-piece body configured to be inserted between an endplate of a first vertebra and an endplate of a second vertebra, the one-piece body having a convex upper surface that is configured to face the endplate of the first vertebra, a convex lower surface configured to face the endplate of the second vertebra, a front body surface, a rear body surface, a right side body surface and a left side body surface spaced from the right side body surface along a lateral direction, and a portion of the one-piece body that is continuous along the lateral direction from the left side body surface to the right side body surface, the one-piece body defining a middle plane disposed equidistantly between the convex upper surface and the convex lower surface, the convex upper surface spaced from the convex lower surface in a first direction, the one-piece body defining a recess that extends at least into the convex upper surface such that the recess defines an opening that is open to the first direction; and

a front plate defining a front plate surface and an opposed rear plate surface, the front plate configured to be mounted to the one-piece body such that the rear plate surface overlies the front body surface, the front plate having a plurality of screw holes, each of the plurality of screw holes configured to receive one of the plurality of bone screws, each of the plurality of screw holes defining a central axis, at least two screw holes of the plurality of screw holes

     1) include an opening in the front plate surface that is positioned between the left side body surface and the right side body surface with respect to the lateral direction; and

     2) extend through the front plate so that the central axis of each of the at least two screw holes is at an oblique angle relative to the middle plane,

wherein the one-piece body is devoid of screw holes with an opening that is positioned beyond the opening of the recess with respect to the first direction, and the front plate is devoid of screw holes with an opening that

     1) is positioned in the front plate surface and

     2) has a center that is positioned beyond the opening of the recess with respect to the first direction when the front plate is mounted to the one-piece body.

36. The system of claim 35, wherein the oblique angle between the central axis of each of the at least two of the plurality of screw holes and the middle plane is from about 20°

to about 60°

.

37. The system of claim 35, wherein the convex lower surface defines a second opening that faces in a second direction that is opposite the first direction, and the one-piece body and the front plate are both devoid of screw holes positioned beyond the second opening with respect to the second direction.

38. The system of claim 37, wherein the one-piece body defines a recess that extends from the opening in the convex upper surface to the second opening in the convex lower surface.

39. A bone stabilizing system comprising:

a plurality of bone screws each having a shaft and a head that is connected to the shaft, the shaft defining a longitudinal central axis;

an integral one-piece body configured to be inserted between an endplate of a first vertebra and an endplate of a second vertebra, the one-piece body having an upper body surface configured to abut the endplate of the first vertebra, a lower body surface configured to abut the endplate of the second vertebra, and a front body surface, the front body surface defines a maximum body height from the upper body surface to the lower body surface; and

a front plate defining an uppermost plate surface and an opposed lowermost plate surface, the front plate defining a front plate surface and an opposed rear plate surface, the front plate defines a maximum plate height from the uppermost plate surface to the lowermost plate surface, such that the maximum plate height is less than the maximum body height, the front plate configured to be mounted to the one-piece body such that the rear plate surface is adjacent to and at least partially overlies the front body surface, the front plate having a plurality of screw holes each configured to receive one of the plurality of bone screws, the plurality of screw holes extending through the front plate and having an axis, at least two of the plurality of screw holes extending through the front plate at an angle relative to the rear plate surface of the front plate so that the axis of the respective screw hole ranges from about 30°

to about 70°

;

wherein at least a portion of the uppermost plate surface is configured to be disposed between the endplates of the first and second vertebrae when the front plate is mounted to the one-piece body and the one-piece body is disposed between the endplates of the first and second vertebrae.

40. The system of claim 39, wherein:

the one-piece body is at least partially formed of plastic and the front plate is at least partially formed of a metallic material;

the at least two screw holes include a first angled screw hole and a second angled screw hole, the first angled screw hole angled in the front plate toward the uppermost plate surface, the second angled screw hole angled in the front plate toward the lowermost plate surface; and

the front plate defines an uppermost plate surface and an opposed lowermost plate surface, at least a portion of the uppermost plate surface is configured to be disposed between the endplates of the first and second vertebrae when the front plate is mounted to the one-piece body and the one-piece body is disposed between the endplates of the first and second vertebrae.

41. The system of claim 39, further comprising a securing plate operatively connectable to the front plate in a manner to at least partially contain at least one of the heads of the plurality of bone screws receivable in one of at least two of the plurality of screw holes between the front plate and the securing plate.

42. The system of claim 39, wherein the upper body surface is spaced from the lower body surface in a first direction, and the one-piece body defines an opening that extends at least into the upper body surface such that the opening is open to the first direction.

43. The system of claim 42, wherein the front plate is devoid of screw holes positioned beyond the opening with respect to the first direction when the front plate is mounted to the one-piece body.