SAVE THE TRAPEZIUM - DOUBLE INTERPOSITION ARTHROPLASTY FOR THE TREATMENT OF STAGE-IV DISEASE OF THE BASAL JOINT

Twenty patients with symptomatic stage IV basal joint (pantrapezial) a rthritis were treated with double interposition arthroplasty, a new te chnique that resurfaces the degenerative trapeziometacarpal and scapho trapezial joints after minimal distal trapezial resection. The results of the 21 procedures were reviewed clinically and radiographically af ter a mean follow-up period of 34 months (minimum, 1 year). Ninety-one percent of the patients were completely satisfied. Seventy-one percen t were entirely free of pain, and an additional 24% noted only occasio nal, mild, high-stress pain that did not limit their activities. One c ase was a clinical failure. Objectively, all 21 basal joints were stab le, with active range of motion to within 90% of normal. Mean grip str ength increased 32%, from a force of 26.1 kg to 33.9 kg (p <.01). Key pinch strength increased from a force of 5.3 kg to 6.0 kg (an 11% incr ease; p =.05). A new method of determining changes in basal joint heig ht indicated a mean decrease in height of 5.3% (range, 0%-12%) at rest and 8.1% (range, 0%-20%) under axial compression. This difference was statistically but not functionally significant. Overall, there were 9 5% good or excellent results and 1 poor result. We believe this techni que is simple and preserves the osseous foundation of the basal joints . These results compare favorably With arthroplasties that include tra pezium excision for the treatment of stage IV basal joint arthritis. C opyright (C) 1998 by the American Society for Surgery of the Hand.