Modular ball and socket joint preferably with a ceramic head ball

Abstract

Modular ball and socket joint has 1) a cupped ball head, preferably of ceramic, having a support body with an inferior, deep, distally facing, preferably generally planar, surface having a substantially circular outer boundary thereto; a distally opening stem receiving bore preferably centrally located in the support body; a cup wall, extending distally from the support body and having a preferably substantially cylindrical inner surface which extends from said outer boundary of said distally facing surface; and a superficially facing, generally semispherical, smooth external surface, preferably and optimally of a low friction coefficient, encapsulating the support body and cup wall; and 2) an interchangable and modular stem, preferably of metal or metal alloy, having a distally directed spike, and a superior stem cap which is insertable into the bore of the head; optionally with 3) a head-receiving articular cup having an inner articular surface and a mountable back surface, the articular surface of which, when the head-receiving cup is suitably mounted in suitable receiving stock, mates in articulating contact with said smooth external surface of said head when said head and stem are suitably mounted in suitable receiving stock. The head and stem modularity allows for noticeably increased versatility and efficiency in surgical procedures, and the ceramic material is beneficially adapted for employment in the fabrication of femoral resurfacing implants for conservative arthroplasty.