Artificial intervertebral disk member

• US 5,370,697 A
• Filed: 02/19/1993
• Issued: 12/06/1994
• Est. Priority Date: 04/21/1992
• Status: Expired due to Term

• Current Assignee: Zimmer GmbH (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Sulzer Medizinaltechnik AG
• Inventors: Baumgartner, Walter
• Primary Examiner(s): ISABELLA, DAVID J
• Application Number:
  US08/019,717
• Time in Patent Office: 655 Days
• Field of Search: 623/17, 623/18, 623/20, 606/61
• US Class Current: 623/17.15
• CPC Class Codes: A61F 2/30965 Reinforcing the prosthesis by embedding particles or fibres during moulding or dipping
• 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 2/4637 for connecting or disconnecting two parts of a prosthesis
• CPC Class Codes: A61F 2002/30016 differing in hardness, e.g. Vickers, Shore, Brinell
• CPC Class Codes: A61F 2002/30065 thermoplastic, i.e. softening or fusing when heated, and hardening and becoming rigid again when cooled
• CPC Class Codes: A61F 2002/30069 elastomeric
• CPC Class Codes: A61F 2002/30387 Dovetail connection
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30505 spring biased
• CPC Class Codes: A61F 2002/30528 Means for limiting said movement
• CPC Class Codes: A61F 2002/30563 having elastic means or damping means, different from springs, e.g. including an elastomeric core or shock absorbers
• CPC Class Codes: A61F 2002/30571 Leaf springs
• CPC Class Codes: A61F 2002/30614 Sets comprising both primary and revision endoprostheses
• CPC Class Codes: A61F 2002/3069 Revision endoprostheses
• CPC Class Codes: A61F 2002/30909 Nets
• CPC Class Codes: A61F 2002/30975 made of two halves
• CPC Class Codes: A61F 2002/4641 for disconnecting
• CPC Class Codes: A61F 2210/0071 thermoplastic
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2250/0019 differing in hardness, e.g. Vickers, Shore, Brinell
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys

Abstract

The artificial intervertebral disk member (1) consists of an upper (2) and a lower (3) support, which are attached in the adjacent vertebrae (32, 33), and of an elastic separator (4). The separator is constructed as a separate insert part (5), which can be inserted from outside into the final position (E) and can be fixed there. The upper support (2) is securely connected to the lower support (3) via the elastic separator (4). This produces a "patient-friendly" implant which can be optimally adapted and revised to suit the patients.

Claims

1. An intervertebral disk member comprising:

an upper and a lower support for attachment to adjacent upper or lower vertebrae;

an elastic separator removably interposable into a final position between the upper and lower supports following their attachment to the adjacent vertebrae and for tightly connecting the upper support to the lower support; and

a reinforcement band surrounding the elastic separator.

13. An intervertebral disk member according to claim 1 wherein the cover plates are made from a titanium alloy.

18. An intervertebral disk member according to claim 1 wherein the elastic separator includes a support member and the supports each include a reinforced edge part, the reinforced edge parts each forming a stop, the stops being sized and positioned to limit relative movement between the first and second vertebrae;

and

the support member, the reinforcement band and the stop each having elastic properties such that the disk member deforms according to three stages, a first soft stage determined by the elastic properties of the support member, a second medium stage determined by the elastic properties of the reinforcement band and a third hard stage determined by the elastic properties of the stop.

2. An intervertebral disk member comprising:

an upper and a lower support for attachment to adjacent upper or lower vertebrae;

an elastic separator constructed as a separate part for insertion into a final position between the upper and lower supports following their attachment to the adjacent vertebrae and for tightly connecting the upper support to the lower support; and

a snap fastener, operably coupled to the elastic separator, for fixing the elastic separator into the final position.

3. An artificial intervertebral disk member for insertion between adjacent upper and lower vertebrae comprising:

an upper support attached to the upper vertebra;

a lower support attached to the lower vertebra;

an elastic separator removably interposable between the upper and lower supports; and

the upper and lower supports each having profile guides, the elastic separator being sized to slide within the profile guides into a final position in which the upper and lower supports are tightly connected to the elastic separator.

4. An artificial intervertebral disk member according to claim 3 further including means for securing the elastic separator into the final position.

5. An intervertebral disk member according to claim 3 wherein the upper support has an upper surface that conforms to a lower surface of the upper vertebra and the lower support has a lower support that conforms to an upper surface of the lower vertebra.

6. An intervertebral disk member according to claim 3 wherein the upper and lower supports are constructed as shells which substantially correspond to a cross section of the upper and lower vertebrae.

7. An intervertebral disk member according to claim 6 wherein the shells each comprise a reinforced edge part.

8. An intervertebral disk member according to claim 7 wherein each reinforced edge part forms a stop, the stop being sized and positioned to limit relative movement between the first and second vertebrae.

9. An intervertebral disk member according to claim 8 wherein the stop includes means to limit movement both in a vertical direction and in directions orthogonal to said vertical direction.

10. An intervertebral disk member according to claim 3 wherein the supports each include an undercut portion, the elastic separator being connected positively to the undercut portion of the upper and the lower supports.

11. An intervertebral disk member according to claim 3 wherein the elastic separator comprises an elastomer support member securely connected to an upper and a lower rigid cover plate.

12. An intervertebral disk member according to claim 11 wherein the cover plates each include an undercut portion, the support member being connected in a positive manner with the undercut portions of the cover plates.

14. An intervertebral disk member according to claim 11 wherein the support member is made from an injected elastomer.

15. The disk member of claim 4 wherein the securing means comprises a retainer spring.

16. The disk member of claim 15 wherein the upper and lower support profile guides include grooves formed in the upper and lower supports.

17. An artificial intervertebral disk member for insertion between adjacent upper and lower vertebrae comprising:

an upper support attached to the upper vertebra and having a lower surface, the lower surface having an undercut portion;

a lower support attached to the lower vertebra and having an upper surface, the upper surface having an undercut portion;

an elastic separator removably interposable between the upper and lower supports, the separator being sized to fit tightly within the undercut portions of the upper and lower supports to thereby connect the supports.