Abstract
Metal-on-metal (MOM) bearings for artificial hip joints have attracted significant attention recently as a way of reducing wear and consequently wear particle induced periprosthetic osteolysis, which is the major cause of failure. One of the most widely used MOM total hip implants is the Metasul system (Zimmer GmbH), in which a thick polyethylene backing is used underneath the metallic inlay. The purpose of this study was to investigate the effect of the polyethylene backing on the transient lubrication under dynamic loading and velocity conditions representative of walking. A 28mm diameter Metasul bearing was analysed, and the predicted lubricant film thickness was compared with that for an all metallic cup. The predicted transient lubricant film thickness in the Metasul system was found to be significantly greater than the corresponding prediction from the all metal cup. Therefore it was concluded that the polyethylene backing may play an important role in the lubrication and overall tribological performance of the Metasul bearing system with a diameter of 28mm.
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
