Vertebral body replacement implant

• US 7,744,650 B2
• Filed: 05/17/2006
• Issued: 06/29/2010
• Est. Priority Date: 05/19/2005
• Status: Active Grant

• Current Assignee: Aesculap AG (B. Braun Holding GmbH & Co. KG)
• Original Assignee: Aesculap AG (B. Braun Holding GmbH & Co. KG)
• Inventors: Maas, Allan, Diehl, Sven, Lindner, Stephan, Beger, Jens
• Primary Examiner(s): Robert; Eduardo C
• Assistant Examiner(s): SCHNEIDER, LYNNSY M
• Application Number:
  US11/436,899
• Publication Number:
  US 20060293755A1
• Time in Patent Office: 1,504 Days
• Field of Search: 606/105, 606/257, 606/258, 623/17.11, 623/17.12, 623/17.13, 623/17.14, 623/17.15, 623/17.16
• US Class Current: 623/17.14
• 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 2/484 Fluid means, i.e. hydraulic or pneumatic
• CPC Class Codes: A61F 2002/30131 horseshoe- or crescent- or C-shaped or U-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 2002/30378 Spherically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30471 connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30581 having a pocket filled with fluid, e.g. liquid
• CPC Class Codes: A61F 2002/30601 telescopic
• 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 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 2220/0091 connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2230/0013 Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped

Abstract

A vertebral body replacement implant having an upper and a lower support plate and two load-bearing elements, the mutual spacing of which is adjustable and of which at least one is connected in an articulated manner to a support plate, the load-bearing element in the region of the articulated connection to the support plate having a bearing projection with a spherical lateral support surface having a complimentary design to the contact surface of the support plate or a bearing part connected thereto, the contact surface extending in peripheral direction at least over 180°, the support plate or the bearing part is mounted on the bearing projection pivotably about a pivotal axis that extends parallel to the support plate, and a releasable clamping device that clamps the bearing projection and the support plate or the bearing part in the contact region of the lateral surface and/or of the contact surface against one another.

Claims

1. A vertebral body replacement implant comprising:

an upper and a lower support plate for positioning against end faces of vertebral bodies;

two load-bearing elements, the mutual spacing of the two load-bearing elements being adjustable;

an articulated connection between at least one of the two load-bearing elements and a corresponding one of the upper and lower support plates, the load-bearing element in a region of the articulated connection to the corresponding support plate having a bearing projection with a spherical lateral support surface,

one of the corresponding support plate or a bearing part connected to the support plate resting with a contact surface, which is of a complimentary design to the spherical lateral support surface, against the spherical lateral support surface of the bearing projection over an angular range that extends in a peripheral direction at least over 180°

, the corresponding support plate or the bearing part being mounted on the bearing projection pivotably about a pivotal axis extending parallel to the support plate; and

a clamping device that clamps the bearing projection, on the one hand, and the corresponding support plate or the bearing part in a contact region of at least one of the spherical lateral support surface and the contact surface, on the other hand, towards one another,

wherein;

the support plate is of a U-shaped design having two substantially parallel limbs connected by a transverse web;

the limbs are disposed on either side of the spherical bearing projection,

the pivotal axis extends parallel to the transverse web;

the clamping device in a clamping position clamps the two limbs towards one another at their free ends remote from the transverse web; and

in the clamping position the bearing projection and the support plate or the bearing part are clamped non-pivotably relative to one another and in a release position are released so that they are freely pivotable relative to one another about the pivotal axis.

2. Implant according to claim 1, wherein the clamping device is a clamping screw that extends parallel to the pivotal axis and rests against the free ends of the limbs.

3. Implant according to claim 2, wherein the longitudinal axis of the clamping screw and the pivotal axis define a bearing plane that extends at a spacing from, and substantially parallel to, a supporting surface of the support plate that is positionable against a vertebral body.

4. Implant according to claim 1, wherein the pivotal axis is defined by a bearing shaft that is adapted to be screwed into the bearing projection.

5. Implant according to claim 1, wherein the bearing part takes the form of a bearing ring that has a dividing slot extending transversely along its circumference.

6. Implant according to claim 5, wherein the bearing ring is disposed in a recess of the support plate and rests with its outer side against an inner wall of the recess.

7. Implant according to claim 6, wherein the recess forms a central opening in the support plate.

8. Implant according to claim 1, wherein the support plate in a region of the transverse web is of an elastically deformable design.

9. Implant according to claim 8, wherein the support plate has a lower thickness in the region of the transverse web than in a region of the limbs.

10. Implant according to claim 1, wherein the limbs and the transverse web on their outer side remote from the load-bearing elements carry laterally outwardly projecting;

plate-shaped supporting surfaces that form an external contour of the support plate.

11. Implant according to claim 10, wherein the two supporting surfaces associated with the limbs form mutually opposite, outer lateral edges of the support plate, the spacing between which edges increases from a ventral side to a dorsal side of the support plate.

12. Implant according to claim 11, wherein the outer lateral edges of the support plate merge via arc-shaped portions into a ventral outer edge of the support plate that extends parallel to the transverse web.

13. Implant according to claim 11, wherein the lateral edges merge via arc-shaped portions into a dorsal outer edge of the support plate.

14. Implant according to claim 11, wherein a central region of the outer lateral edges is curved inwards.

15. Implant according to claim 14, wherein an inwardly curved region of the outer lateral edges of the support plate is of an arc-shaped design.

16. Implant according to claim 14, wherein an inwardly curved region of the outer lateral edges directly adjoins arc-shaped portions of the outer lateral edges, via which arc-shaped portions the outer lateral edges merge into ventral and dorsal outer edges of the support plate.

17. Implant according to claim 10, wherein the supporting surface associated with the transverse web has in its central part an indentation that is open in a direction of a ventral outer edge of the support plate.

18. Implant according to claim 10, wherein the supporting surfaces associated with the transverse web and the limbs jointly surround a central opening that is open in a direction of a dorsal outer edge of the support plate.

19. Implant according to claim 18, wherein the opening is of a circular design.

20. Implant according to claim 18, wherein the central opening via a radial slot is open in the direction of the dorsal outer edge.

21. Implant according to claim 10, wherein in a dorsal outer edge of the support plate a central, recessed portion is disposed.

22. Implant according to claim 21, wherein the recessed portion is of a semicircular design.

23. Implant according to claim 18, wherein at an edge of the central opening, outwardly projecting fixing projections are disposed.

24. Implant according to claim 23, wherein the fixing projections have a shape of thorns or points.

25. Implant according to claim 10, wherein holes are provided in the supporting surfaces.

26. Implant according to claim 18, wherein lateral recesses are disposed in an edge of the central opening.

27. Implant according to claim 1, wherein the articulated connection connects both load-bearing elements to a corresponding support plate.

28. Implant according to claim 4, wherein the bearing shaft, in a support plate with bearing parts, passes through both the bearing part and an opening in the support plate.

29. Implant according to claim 3, wherein the clamping screw in a screw-in region is coated with titanium oxide.

30. Implant according to claim 1, wherein the support plate is provided with a bone-friendly coating.

31. Implant according to claim 30, wherein fixing projections of the support plate are excepted from the bone-friendly coating.