Silicone arthroplasty for trapeziometacarpal arthritis.

Twenty-three patients who had undergone trapeziectomy and Helal silicone rubber ball interposition for trapeziometacarpal arthritis were reviewed. The average age at operation was 63 (range 48-84) years and the mean follow-up was 59 (range 12-138) months. Of the 23 patients reviewed, two had pain at rest and four had some discomfort on exertion. Mean post-operative thumb extension was 37 degrees whilst mean palmar abduction was 40 degrees. Mean post-operative grip strength was 19 kg and thumb-pinch strength was 4.0 kg, 77% and 78% of the age- and sex-matched normal values. There were no cases of prosthetic dislocation, prosthetic fracture or silicone synovitis.