A l3-year-old boy lacerated the palm on broken glass, but only the wound was sutured in the emergency room and no attempt was made to repair the nerve . Five months later there was severe pain in the median nerve distribution, marked thenar weakness with atrophy of the abductor pollicis brevis muscle, and a posit.ive Tinel 's sign. At operation the median nerve was found to divide into three branches in the carpal tunnel, and a median artery was present. A great deal of scar tissue was present, and it appeared that only the one branch to the thenar muscles had been severed. This was repaired under the microscope by direct neurorrhaphy without tension. In 7 months there was no return of opposition and because the patient was unable to use the thumb well, an opponensplasty was done using the flexor superficial is tendon of the ring finger. The Palazzi technique was used for the pulley, and the Brandl type of insertion into the thumb was used. A Brand tendon passer was used to pass the tendon blindly through the palm. Immediately after the operation, he had minimal pain, and some numbness and tingling was noted in the fingertips, which was relieved by splitting the plaster dressing. Three weeks later therapy was begun, and by the fifth week he was using the thumb well. However , numbness and tingling occurred in the areas of distribution of the ulnar and median nerves . Soon there was almost complete sensory loss of the hand , with clawing of all of the fingers . The hand became much more anesthetic as the function improved in the opponensplasty. An electromyogram (EMG) study at this time showed that there was complete conduction loss of both the ulnar and median nerves at the wrist. Because of these findings a reexploration was done. At operation it was found that two branches of the median