Abstract
Nine patients with osteoarthrosis of the carpo-metacarpal joint of the thumb were treated surgically with the metacarpo-trapezial silicone rubber prosthesis designed by Kessler. Patients with pantrapezoidal changes were specifically excluded. All patients at follow-up had chronic synovitis and in five the prosthesis was dislocated. In three patients who had revision operations the previously inserted prostheses were found to be badly torn.