Arthrolysis can be performed for posttraumatic stiffening of elbow and knee joints if all conservative treatment has failed. The mobility gained during the operative procedure is partly lost during the first two to three postoperative weeks. Intensive physical therapy is essential to maintain the mobility. In a follow-up study all 19 patients, who underwent arthrolysis from 1983 up to 1989, were re-examined. Considering the relative increase of motion the result was good in nine patients, moderate in six and poor in four patients. Arthrolysis is not an innocent procedure. However, if strict pre-operative conditions are considered, good results can be obtained.