Patent ID: 7223290

Claim:
An intervertebral spacer device, comprising: a first baseplate, having an outwardly facing surface and an inwardly facing surface, the inwardly facing surface having a central post extending therefrom, the post having a longitudinal axis and a head end that is inwardly directed toward the second baseplate; a second baseplate, having an outwardly facing surface and an inwardly facing surface, the second baseplate's inwardly facing surface having a curvate pocket formed by a central portion of the second baseplate's inwardly facing surface concaving outwardly to define a semispherical contour; a convex structure having an outwardly facing surface and an inwardly facing surface, the convex structure further having a central bore extending from the convex structure's inwardly facing surface to the convex structure's outwardly facing surface, the convex structure's central bore having an opening on the convex structure's outwardly facing surface that is surrounded by a curvate taper defining a semispherical contour; and a ball defining a spherical contour, the ball having a central bore; wherein the ball is seatable in the curvate pocket; and wherein the convex structure's outwardly facing surface is securable to the second baseplate, the securing of the convex structure to the second baseplate establishing a curvate socket formed by the second baseplate's curvate pocket and the convex structure's curvate taper, the curvate socket defining a spherical contour; and wherein the ball is thereby capturable in the curvate socket, with the curvate socket's spherical contour accommodating the ball's spherical contour for rotation and angulation of the ball in the curvate socket about a central portion of the ball; and wherein the post is disposable through the convex structure's central bore and the post's head end is securable to the ball's central bore, such that the post is accommodated for rotation in the convex structure's central bore about the post's longitudinal axis as the ball rotates in the curvate socket, and such that the post is accommodated for angulation in the convex structure's central bore about the ball's central portion as the ball angulates in the curvate socket; and wherein the second baseplate includes a first part having the inwardly facing surface having the curvate pocket of the second baseplate, and a second part having the outwardly facing surface of the second baseplate; and further comprising a spring member disposed between the first part and the second part such that a compressive load applied to the outwardly facing surfaces of the baseplates is borne by the spring member.