2010 年 5 巻 1 号 p. 24-31
The success of total hip arthroplasty (THA) in improving joint function and reducing pain is regarded as one of the great achievements of modern medicine. Today, most femoral stems with cementless fixation are made of either cobalt-chrome-molybdenum (CoCrMb) or titanium-aluminum-vanadium (TiAlV) alloys. In order to obtain adequate initial stability of the cementless femoral stem, the implant must be placed in contact with bone of sufficient strength to support the prosthesis rigidly. This study introduces a unique approach in this research category, making use of shape memory alloys (SMA) for cementless stems to obtain adequate initial stability. Using SMA that exhibits a shape memory effect, better proximal fit and fill with smooth insertion will be accomplished. In this study, numerical evaluation is intended with initial stability of a cementless stem for which SMA is utilized. A result of the numerical analysis reveals that use of SMA is found to be effective enough to obtain rigid initial stability.