Fracture of polyethylene acetabular cups. Report of two cases
Most of the mechanical failures in prostheses after total hip replacement involve fatigue fracture of the metallic femoral stem. To our knowledge, however, fracture of the ultra high-molecular-weight polyethylene acetabular cup has not been previously reported. We are presenting two patients in whom the polyethylene cup fractured, in one four and one-half years and in the other six and one-half years after implantation of the prosthesis.