Wear and Migration in the Corin Mini-Hip/Metafix and ECIMA Polyethylene

The primary objective of this study is to determine whether the Mini Hip (Corin, U.K.) femoral component has a predictable and stable migration pattern (mean migration of the femoral component in three-dimensions,in mm) over a three year period, compared to a conventional cementless stem (Metafix, Corin, U.K.). The secondary objectives of this study are to determine whether the Trinity (Corin, U.K.) acetabular component has a predictable and stable migration pattern over a three year period and to measure the linear wear of femoral head into the ECIMA Highly Cross-linked polyethylene.