[Ten years experience with the cementless alloclassic cup according to zweymüller.]

Because our department of orthopaedic surgery deals with the cementless hip replacement for more than 15 years, we have performed a retrospective study and a critical analysis of our patients. In the time between 01. 05. 1987 and 31. 12. 1989 we implanted 206 primary cement-free total endoprostheses of the hip in 190 patients. After an average time taken for postoperative check-ups of ten years and seven months we evaluated 133 hips (64,6 %) in 123 patients (64,7 %) clinically and radiologically. The clinical postoperative check-up according to the score of Merle d'Aubigne demonstrated very good and good results in 90 % of our cases. After 10,6 years the radiological measurement showed an average polyethylene wear of 1 mm. The critical analysis of our patients amounted to 3 % of cup complications.The therapy with the reoperations of 9 patients (6,7 %) will also be discussed. In the discussion we are concerned with the results and problems of other authors, who are engaged with the cementless hip replacement. Summarizing we can declare, that the cementless Alloclassic cup to Zweymüller has a lot of advantages: ideal primary stability simple surgical technic optimal bony incorporation low polyethylene wear For the future we recommend a change of the headsize from 32 mm to 28 mm. In young and active patients we propose a metal-metal or a ceramic-ceramic pairing. Key words: cementless cup, primary stability, low polyethylene wear, 28 mm headsize.