Objective: Clinical and radiological comparison of unconstrained and constrained knee endoprostheses in revision total knee arthroplasty after septic or aseptic loosening in consideration of quality of life, activity and patella related problems.

Material and methods: 26 patients with 10 hinge pros-theses and 16 condylar prostheses were examined using the following scores: HSS, Knee Society Score, Visual Analogueue Scale, Tegner Activity Score, Patella Score, SF-36-helth questionaire. Before implantation all hinge endoprostheses were septic and all condylar endopros-theses aseptic. For radiological examination the Knee Society and Engh Score were used.

Results: There were no significant deviations in clinical parameters between the types of prostheses resp. septic or aseptic history. Radiological parameters deviated significantly in only one parameter: the femoral defects in hinge prostheses were significantly larger (p=0.0036). Regarding at patients with hinge prostheses compared with healthy subjects of the same age deviated significantly only in limitations in physical activities because of health problems, limitations in usual role activities because of physical health problems and bodily pain. In the group of condy-lar endoprostheses there were significant deviations for all items except vitality and general mental health.

Conclusion: The choice of condylar or hinged endopros-theses does not have any significant influence on clinical results, neither has aseptic or septic history. The quality of life results of condylar prostheses were inferior.