Compared to the frequency of manifestation of rheumatoid arthritis in the elbow joint the quota of surgical intervention in this area is low. In most cases pain and disability are only moderate, especially if the reduced range of motion is compensated by maintained function of the equilateral shoulder and wrist joint. Surgical treatment is indicated if instability increases, the independency of the patients in daily life is endangered and inflammation increases acutely. A persistent compression of n. ulnaris has to be operated as soon as possible. Often the preferred early synovectomy is impossible because of priority of other joints. By late synovectomy, however, good results can be expected regarding stability, function and extent of pain. In our cases the joint was opened from radial and ulnar in combination with ventralization of the ulnaris nerve. The replacement of the head of radius by a silastic-spacer seems to reduce the secondary irritation in the radial part of the joint and to increase stability. The own method for resection-arthroplasty in modification of the method of Hass with interposition of the middle part of triceps tendon is described and discussed. Because of imminent loosening prostheses are implanted very rarely.