Rupture of the distal insertion of the biceps brachii tendon is a rare injury. There has been no unanimity in the literature concerning the best method of repair. Between March 1981 and July 1984, 14 ruptures (12 acute and two late) were repaired using a modification of the Boyd-Anderson technique. Cybex testing of the elbow flexion by applying an eccentric load demonstrated that strength and endurance in the repaired dominant arm were roughly equal to the noninjured, nondominant arm, but that strength and endurance of the repaired nondominant arm were only 64% and 50%, respectively, of the noninjured dominant arm. Surgical repair is a safe procedure that yields consistently good results.