120 hips in 100 patients undergoing primary, cement-less Total Hip Arthroplasty were randomized to received a short, metaphyseal-fitting femoral component, and another group received a conventional metaphyseal- and diaphyseal- filling femoral component. They were followed up for 3.35 years. Bone mineral density was significantly increased in femoral zone 1 but slightly decreased in zone 7 in the short, metaphyseal-fitting stem group. In the conventional metaphyseal- and diaphyseal-fitting stem group, bone mineral density was markedly decreased in both zones 1 and 7. Comparable clinical and radiographic outcomes were noted in the 2 groups. No hip in either group required revision of the component.