Evaluation of carpal canal pressure in carpal tunnel syndrome.

Preoperative electrophysiologic testing and intraoperative carpal canal pressure measurements were performed on 957 hands in 647 patients with clinical signs of carpal tunnel syndrome. Fifty-five symptomatic hands in 48 patients were normal in both distal sensory latency and distal motor latency preoperatively. Carpal canal pressure was, however, significantly elevated compared to control data in all 55 hands. After complete subcutaneous release of the carpal canal using the Universal Subcutaneous Endoscope system, carpal canal pressure was reduced to within the normal control range. Clinical symptoms of carpal tunnel syndrome improved in all 55 hands. Postoperative electrophysiologic data remained within normal range in patients who agreed to receive electrophysiologic examinations.