Highly Cross-Linked Polyethylene

Highly radiation–cross-linked, subsequently melted ultrahigh molecular weight polyethylene (XLP) has rapidly gained wide acceptance in total joint arthroplasty as a means to markedly reduce wear and the associated periprosthetic osteolysis. Several laboratory studies have shown negligible wear of XLP in both hip and knee for durations simulating 20 years of in vivo service. Three clinical studies involving 3 different demographic groups and 2 different measurement techniques have found that the femoral head penetration after bedding-in is less than 10 mm/y. Retrieval acetabular and tibial specimens up to 3 years after insertion have confirmed the absence of wear and oxidation. With in vivo experience now over 5 years, it appears that XLP is the material of choice in total joint arthroplasty.