Osseointegrated silicone implants. 18 patients with 57 MCP joints followed for 2 years.

20 patients were operated on consecutively with osseointegrated MCP joint prostheses in 64 joints at our department between September 1993 and February 1995. The one-stage procedure included joint resection and cancellous bone grafting from the iliac crest before insertion of screw-shaped titanium fixtures, connected with a flexible silicone spacer. 18 patients (57 joints) were clinically and radiographically examined at median 28 (18-37) months postoperatively. Indications for surgery were joint destruction due to chronic arthritis in 17 patients (56 joints), and posttraumatic arthrosis in 1 patient (1 joint). Postoperative median range of motion was 40 (15-85) degrees, with an extension deficit of 30 (-20-70) degrees. 16 patients were satisfied, and had good pain relief and substantially improved postoperative hand function, evaluated with the standardized Sollerman hand function test. Radiographic osseointegration was obtained in 112 of 114 titanium fixtures (98%), but fracture of the silicone spacer was observed in 14 implants (25%). We conclude that osseointegration of longitudinal titanium fixtures in the bone marrow canal is possible in a one-stage procedure, but our findings show the need for a new, more durable joint spacer.