Abduction-opposition wedge osteotomy of the first metacarpal bone was performed in 8 patients (10 joints) with osteoarthritis of the thumb CM joint which had resisted various conservative treatments. Within 6 months after the operation, good results were obtained in 6 cases (8 joints) . In periodic postoperative X-rays, widening of the thumb CM joint space was also observed in 8 joints (average follow-up period : 3.5 years) .
