The purpose of this study was to evaluate the clinical and radiological results using S-ROM prosthesis in patients with type C and B femoral bone requiring primary total hip arthroplasty (THA) for multiple reasons.Sixteen hips were followed up for a mean of 38 months (range, 26–48), with a mean age at surgery of 72 years (range, 65–75).The average Harris hip score improved from 52.2 points to 88.5 points. All femoral stems showed stable fixation. Neither osteolysis around the femoral stem nor subsidence of the femoral stem were found at the final follow-up.For the patients with poor bone quality, total hip arthroplasty with the use of the proximal modular femoral stem yielded good short-to-mid-term results with respect to the clinical and radiological criteria.