[Patellar changes following knee joint endoprosthesis-plasty].

We analysed the postoperative position of the patella and the degenerative changes in 80 implanted Guepar, Tillmann and GSB-prostheses of the knee. We did not found differences between the types of endoprostheses. We saw many dislocations of the patella, especially in patients with rheumatism, but only some patients had trouble with the operated knee. We can diminish these problems by modelling of the patella and by careful reconstruction of the muscle strength.