[Technique, results and risks of endoscopic carpal tunnel release]

Endoscopic carpal tunnel release was performed in 168 cases of carpal tunnel syndrome using the two-portal technique described by Chow. There were 164 cases of idiopathic carpal tunnel syndrome and four cases following a wrist trauma. Sensory symptoms improved within few days in 113 patients (67%) and in 141 cases within eight weeks (84%). Nighttime pain relief was achieved immediately in 87% of the patients and in 94% within eight weeks. Grip strength increased to preoperative values within eight weeks and pinch strength reached preoperative levels within six weeks. In four cases an iatrogenic injury of the superficial palmar vascular arch occurred. In another four patients, open revisional surgery had to be performed. Three of these patients presented an incomplete release of the retinaculum flexorum and in one patient a remaining part of the palmar fascia led to further compression of the median nerve despite complete dissection of the carpal ligament.