Pathologic studies of total joint replacement.

Articular endoprostheses are, in effect, foreign bodies designed to re-establish functioning articulations and are, therefore, capable of eliciting a local or systemic response to their presence. This article discusses the body's reactions to foreign bodies in general, and to endoprostheses in particular, and attempts to place those reactions into perspective regarding survival and failure of articular endoprostheses. The effects of size, shape, and composition of the materials used in the prosthetic components, and the mechanical factors acting on them to produce debris, are presented.