[Status of the endoprosthesis in rheumatic metacarpophalangeal joints. Long-term results of metacarpophalangeal prostheses using Swanson's silastic spacers].

Advanced rheumatoid destruction of the metacarpophalangeal joints frequently requires implant arthroplasty. Among many different types of implants, the Swanson-Silastic-spacer is widely used. The long-term results of 102 arthroplasties of the metacarpophalangeal joint were assessed in 28 rheumatoid patients (34 hands) 10.1 years postoperatively on the average. Marked relief of pain was found in all patients. 75% of the patients reported functional improvement of the hand. Active range of motion decreased from 42 degrees preoperatively to 36 degrees postoperatively on the average. Ulnar drift was corrected from an average of 34 degrees preoperatively to 12 degrees postoperatively. The average extension deficit had improved from 33 degrees at surgery to 11 degrees at the time of follow-up. Grip strength remained unchanged. The radiographical findings showed surrounding osteolysis in 89.4% of the implants and 27.5% broken spacers. In comparison to other types of finger implants, Silastic-spacers showed similarly limited all over results, however, there seem to be less problems in salvage procedures.