title: Surface grafting of artificial joints with a biocompatible polymer for preventing periprosthetic osteolysis.
abstract: Periprosthetic osteolysis-bone loss in the vicinity of a prosthesis-is the most serious problem limiting the longevity of artificial joints. It is caused by bone-resorptive responses to wear particles originating from the articulating surface. This study investigated the effects of graft polymerization of our original biocompatible phospholipid polymer 2-methacryloyloxyethyl phosphorylcholine (MPC) onto the polyethylene surface. Mechanical studies using a hip-joint simulator revealed that the MPC grafting markedly decreased the friction and the amount of wear. Osteoclastic bone resorption induced by subperiosteal injection of particles onto mouse calvariae was abolished by the MPC grafting on particles. MPC-grafted particles were shown to be biologically inert by culture systems with respect to phagocytosis and resorptive cytokine secretion by macrophages, subsequent expression of receptor activator of NF-kappaB ligand in osteoblasts, and osteoclastogenesis from bone marrow cells. From the mechanical and biological advantages, we believe that our approach will make a major improvement in artificial joints by preventing periprosthetic osteolysis.
authors.affiliation: Department of Sensory & Motor System Medicine, Faculty of Medicine, The University of Tokyo, Hongo 7-3-1, Bunkyo, Tokyo 113-0033, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Moro
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Takatori
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ishihara
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Konno
authors.forename: Yorinobu
authors.initials: Y
authors.lastname: Takigawa
authors.forename: Tomiharu
authors.initials: T
authors.lastname: Matsushita
authors.forename: Ung-Il
authors.initials: UI
authors.lastname: Chung
authors.forename: Kozo
authors.initials: K
authors.lastname: Nakamura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawaguchi
mesh_terms: D001672:Biocompatible Materials; D007595:Joint Prosthesis; D008689:Methacrylates; D010014:Osteolysis; D010767:Phosphorylcholine / Q000031:analogs & derivatives*; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D008689:Methacrylates; D010767:Phosphorylcholine; C070638:2-methacryloyloxyethyl phosphorylcholine