Artificial disc and joint replacements with modular cushioning components
View Patent ↗An artificial joint or disc replacement (ADR) broadly includes a pair of opposing endplate components, each attached to one of the upper and lower vertebrae, a cushioning component disposed between the endplate components, and a mechanism for coupling the cushioning component to one or both of the endplates. In the preferred embodiment, the cushioning component takes the form of a tire-like outer structure attached to an inner hub. A filler material is also preferably contained within the cushioning component. The filler material may be a gas, liquid, foam, or gel, including a hydrogel. One or both of the endplate components may include a modified surface to increase adherence to respective opposing bone surfaces.
1. A modular implant configured for placement between opposing bone surfaces, comprising:
a pair of opposing endplate components, each attached to one of the opposing bone surfaces;
a cushioning component having an outer, compressible structure with crossing overlapping fibers attached to a central hub; and
mechanism associated with the central hub for interlocking the cushioning component to one or both of the endplates.
2. The implant of claim 1 , wherein the cushioning component includes a filler material.
3. The implant of claim 2 , wherein the filler material is a gas, liquid, foam, gel or hydrogel.
4. The implant of claim 2 , wherein one or both of the endplate components include a modified surface to increase adherence to respective bone surfaces.
5. The implant of claim 4 , wherein the modified surface includes spikes or other projections.
6. The implant of claim 4 , wherein the modified surface is conducive to bony ingrowth.
7. The implant of claim 1 , wherein the mechanism for interlocking the cushioning component to one or both of the endplates includes a projection on the central hub and a corresponding groove on the endplate allowing the implant to be pushed into position.
8. The implant of claim 7 , further including a screw or other fastener for maintaining the projection in the groove.
9. The implant of claim 1 , further including a clip or other device for compressing the implant until insertion between the opposing bone surfaces.
10. The implant of claim 1 , wherein the endplates are configured for adherence to vertebral endplates.
11. The implant of claim 1 , wherein:
one of the endplates is configured for adherence to a prepared distal femur; and
the other of the endplates is configured for adherence to a prepared proximal tibia.