MASSIVE OSTEOLYSIS INDUCED BY HIGH-MOLECULAR-WEIGHT POLYETHYLENE WEARDEBRIS

We investigated the mechanism by which particulate wear debris of poly ethylene may induce bone resorption using an in vivo model. Two unceme nted total hip prostheses, in which the socket was directly in contact with acetabular bone, were selected because there was massive bone bo ss around the implant. A thick synovium-like layer was found at the po lyethylene-bone interface during revision operations. Samples were exa mined by transmitted and polarised light microscopy, and by transmissi on electron microscopy. This study demonstrates that polyethylene wear products alone can cause massive osteolysis by triggering the formati on of foreign body granuloma at the bone-implant interface.