Opponensplasty using the extensor indicis proprius routed subcutaneously around the ulnar side of the forearm and across the palm to the extensor pollicis longus tendons in the region of the thumb metacarpophalangeal joint restored excellent thumb function in fifty-seven of sixty-five forearms: nineteen with low and thirteen with high median-nerve injuries and seventeen with high and fourteen with low combined median and ulnar nerve injuries, and two brachial plexus injuries. The main indications for this procedure are a high median-nerve injury and any combined median and ulnar-nerve injury.