Internal neurolysis or ligament division only in carpal tunnel syndrome. II. A 3 year follow-up with an evaluation of various neurophysiological parameters for diagnosis.

48 patients with clinical and neurophysiological signs of carpal tunnel syndrome were randomized to any of two operative methods: Internal neurolysis of the median nerve with a microsurgical technique, or simple division of the carpal ligament (flexor retinaculum). After a minimum follow-up period of 3 years 81% of the patients did not report any complaints at all, and all patients considered themselves improved after operation. There was no difference between the operation groups. Therefore there seems to be no justification to perform the more difficult procedure of internal microsurgical neurolysis for treatment of the carpal tunnel syndrome. A study of the neurophysiological parameters before and after restitution showed the highest sensitivity (91%) for the sensory conduction velocity, and the highest specificity for motor distal latency and sensory distal latency (83 and 75% resp.).