Résumé : Twenty-eight metastases of the proximal femur were treated by resection and by prosthetic replacement using a large femoral component with diaphyseal support (megaprosthesis). When metastatic involvement of the acetabulum was not evident a mobile self-centering cup was used (bipolar hip arthroplasty: 17 cases). When metastatic destruction of the acetabulum was evident acetabular reconstruction was performed (total hip arthroplasty: 11 cases). Postoperative pain relief according to Habermann was excellent in 81.5% and good in 14.8% of the patients. The functional results according to Merle d'Aubigné were rated as excellent in 19%, very good in 22%, and good in 22% of the hips. The rate of postoperative dislocation was significantly lower (p < 0.05) in the bipolar arthroplasty group when compared to the total hip arthroplasty group. Our experience indicates that, when bone disease of the acetabulum is not evident, a bipolar arthroplasty rather than a total hip arthroplasty should be recommended. In the current series pain relief as well as postoperative walking ability were comparable in both groups but the dislocation rate was significantly lower with bipolar arthroplasty.