SEMI-CONSTRAINED TOTAL KNEE ENDOPROSTHESI S FOR SEVERE INSTABLE GONARTHROSIS OR AS REVISION IMPLANT

42 patients with 45 implanted total knee endoprostheses (sliding axis endoprosthesis Lubeck, Rp. SG implant) were investigated clinically ac cording to the score of the Knee joint Society in mean 27.9 months pos toperatively. Mean total knee score increased from 34.9+/-14.7 to 72.5 +/-3.1 and mean total functional score could be ameliorated from 40.2/-25.7 to 55.7+/-4.5 (maximum points: 100). Evaluation of X-rays (ante rior-posterior and lateral views) exhibited a satisfactory position of the prosthesis. Comparison between cemented and cementless implants a s well as between primary implants and revision did not reveal any sta tistically significant differences. Patients with a longer follow-up p eriod (59.8 months) showed results comparable to the mean of the total group. Frequently observed malposition of the axis of more than 3 deg rees requires modifications of the orientation instruments. For revisi on surgeries a modular system for elongation of the stem would be desi rable.