Patent ID: 7402176

Claim:
An intervertebral disc prosthesis assembly comprising: (a) a first base plate comprising a circumferential edge, an interior surface, an exterior surface and a first threaded groove extending into the circumferential edge along the interior surface; (b) a second base plate disposed opposite the first base plate, the second base plate comprising a circumferential edge, an interior surface, an exterior surface, and a second threaded groove extending into the circumferential edge along the interior surface, the second threaded groove disposed opposite and facing the first threaded groove; and (c) a threaded rod that engages the first and second threaded grooves of the first and second base plates; wherein the interior surface of the first base plate has a first cup disposed thereon, the first cup defining a first concave surface, and the interior surface of the second base plate has a second cup disposed thereon, the second cup defining a second concave surface, and further wherein the disc prosthesis system further comprises a disc insert comprising two opposing convex surfaces disposed between the first and second concave surfaces.