Total Hip Replacement: Metal-on-Metal Systems

Abstract

Arthroplasty has been performed since the 1800s, when it was used to correct hip deformity in patients (Jayson, 1971). As the years progressed, material considerations became more important as well as the method of fixation of the components. Total replacement arthroplasty began in the early 1950s, with the work of Charnley and of McKee. McKee began his work with femoral and acetabular components made of stainless steel and cemented into the bone using acrylic cement. He later chose a cobalt-chrome alloy as his material of choice. Advantages of this material choice for the hip prosthesis, according to McKee, include tolerance to body tissues, low wear, and low friction. Loosening is a major concern in his design (McKee and Farrar, 1966). Other types of prostheses include the Stanmore prosthesis, which progressed from all cobalt-chrome (with three pins cemented into the ilium for extra support) to an articulating pair of cobalt-chrome/polyethylene, the Charnley prosthesis, which used ultrahigh molecular weight polyethylene (UHMWPE) for the acetabular component and a metal femoral stem and head; and the Muller self-lubricating hip prosthesis, which was a metal-onmetal system with plastic bearing in the acetabular component for the reduction of friction.