Clinical outcome in total hip arthroplasty using a cemented titanium femoral prosthesis.

Between 1988 and 1993, 118 total hip arthroplasties were carried out using cemented titanium alloy stems with modular cobalt-chrome heads. At a mean follow-up of 66.2 months, the overall clinical failure rate as a result of aseptic loosening of the femoral stem was 11.5%. Most failures occurred with smaller stems, especially in heavier patients. Clinical and radiographic data suggest that failure of femoral component fixation was due to high stresses in the cement mantle associated with the increased flexibility of the smaller stems. Radiographs of successful arthroplasties in patients with larger stems showed proximal stress shielding in most. The findings in this study do not support the contention that titanium alloys provide an advantage over more rigid materials in the manufacture of cemented femoral components for total hip arthroplasty.