[Progress of research in osteoarthritis. Invention of longer lasting artificial joints].

In the advent of the aging society, the lifetime of artificial joints is a matter of concern. The major cause of revision surgery is periprosthetic osteolysis caused by polyethylene wear particles. To prevent osteolysis, both the reduction of wear and the suppression of osteoclast induction are necessary. For these purposes, we developed a new technology for grafting 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer on the surface of polyethylene liners. On the basis of encouraging results of the preclinical studies, we have started a large-scale clinical trial of new artificial hip joints since 2007.