Cementless acetabular component St. Nabor. clinical and radiographic results after medium term follow-up.

The aim of the retrospektive study was to analyse the medium-term results o f the cementless hip prosthesis St. Nabor. Method: 46 patients with complet e postoperative and radiographic documentation were available for clinical review. The average follow-up was eight years and five months (range from e ight years, one month to ten years). The average age at the last follow-up was 60 years. Ten patients showed severe coxarthritis and 32 patients a dys plasia of the acetabulum before surgery. Two patients suffered from a sever e osteonecrosis of the femoral head and two patients had fractures of the a cetabulum or femoral neck, respectively. Results: The medium-term follow-up for the acetabular component showed a survival Fate of 97.8%. The radiogra phic data visualized one loosening as a result of a low grade infection, 18 months after surgery. There was no migration of the acetabular component a ccording to Sutherland et at. and no protrusion was found. None of the acet abular components showed radiolucent lines or was loose according to radiog raphic criteria. In comparison to the first post-operative radiograph, 26 o f the hips were found with a significant reduction of lacunae, twelve of th em showed a complete absence at: last follow-up. The overall Harris hip sco re averaged 92 points (range 58 to 700 points) for the entire group. 41 (92 %) of all hips were rated as excellent or good. Two hips (4%) of all hips w ere rated as fair and two hips (4%) were rated as poor. Conclusion: The hig h rate of good and satisfying results in medium-term follow-up proves this St. Nabor acetabular component system to be an excellent implant in total h ip arthroplasty For younger patients with or without dysplasia.