Clinical results of the Metha short hip stem: a perspective for younger patients?

Abstract

In recent years, various uncemented proximal metaphyseal hip stems were introduced for younger patients as a bone preserving strategy. Initial osteodensitometric analyses of the surrounding bone of short stems indicate an increase of bone mass with secondary bone ingrowth fixation as a predictor of long-term survival of these types of implants. We report the outcome of 151 modular Metha short hip stem implants in 148 patients between March 2005 and October 2007. The mean follow-up was 5.8±0.7 years and the mean age of the patients was 55.7±9.8 years. Along with demographic data and co-morbidities, the Harris Hip Score (HHS), the Hip dysfunction and Osteoarthritis Outcome Score (HOOS), and also the results of a patient-administered questionnaire were recorded pre-operatively and at follow-up. The mean HHS increased from 46±17 pre-operatively to 90±5 the HOOS improved from 55±16 pre-operatively to 89±10 at the final follow-up. A total of three patients have been revised, two for subsidence with femoral revision and one for infection without femoral revision (Kaplan Meier survival estimate 98%). The radiological findings showed no radiolucent lines in any of the patients. The modular Metha short hip stem was implanted in younger patients, who reported an overall high level of satisfaction. The clinical and radiographic results give support to the principle of using short stems with metaphyseal anchorage. However, long-term results are necessary to confirm the success of this concept in the years to come.