Difficulties and early results of the endoscopic carpal tunnel release using the modified Chow technique.

In reporting on the preliminary results of our series of 76 patients, this paper aims to identify potentially complicating aspects of endoscopic carpal tunnel release (ECTR) using the two-portal Chow technique, and to recommended solutions, based on our early experience, which enhance the ease and safety of this minimally invasive technique. Of the first 24 patients, 16 cases required conversion to an open procedure. Based on these initial cases, we developed certain modifications of the Chow technique which precluded any need for open conversion in the 60 remaining cases. During a follow-up interval ranging from 4 to 24 months, there was no recurrence of carpal tunnel symptoms, and the average time to resumption of work activity was 14 days. The complication rate was 5% and included one case of transient hypesthesia, one case of extended hematoma, and one hypersensitive scar. All complications resolved at subsequent follow-up. In our experience, correct positioning of the hand, proper injection of local anesthetic, use of magnifying loupes, and correct use of instruments are essential for a safe and successful procedure.