3369: High resolution ultrasonography of carpal tunnel syndrome: A dynamic evaluation

Abstract

Objectives: To assess the median nerve in carpal tunnel with motion of the wrists and hands.Methods: Seventy wrists of 50 patients with proved carpal tunnel syndrome were enrolled (group A). The 30 asymptomatic wrists (group B) and 50 wrists of 25 volunteers (group C) were scanned for comparison. Axial high resolution ultrasonography (HRUS) scanning of wrists through the pre-tunnel, proximal tunnel and distal tunnel with wrists in neutral and extension, and fingers in rest and flexion was performed. The shape, cross-sectional area (CSA) and flattening ratio (FR) of median nerve were assessed. The sliding distance of median nerve with motion of wrists and hands were recorded.Results: With wrists in neutral position and fingers in rest, the mean CSA of the median nerve were significantly enlarged in group A. The mean FR of the median nerve at proximal tunnel level was significantly increased in group A. With wrists in extension position and fingers flexion, the mean distance of median nerve sliding was significantly decreased in group A and group B.Conclusions: The HRUS might be useful for the evaluation of carpal tunnel syndrome. The decrease in mobility of the median nerve in the carpal tunnel might be a predisposing factor of carpal tunnel syndrome. Objectives: To assess the median nerve in carpal tunnel with motion of the wrists and hands. Methods: Seventy wrists of 50 patients with proved carpal tunnel syndrome were enrolled (group A). The 30 asymptomatic wrists (group B) and 50 wrists of 25 volunteers (group C) were scanned for comparison. Axial high resolution ultrasonography (HRUS) scanning of wrists through the pre-tunnel, proximal tunnel and distal tunnel with wrists in neutral and extension, and fingers in rest and flexion was performed. The shape, cross-sectional area (CSA) and flattening ratio (FR) of median nerve were assessed. The sliding distance of median nerve with motion of wrists and hands were recorded. Results: With wrists in neutral position and fingers in rest, the mean CSA of the median nerve were significantly enlarged in group A. The mean FR of the median nerve at proximal tunnel level was significantly increased in group A. With wrists in extension position and fingers flexion, the mean distance of median nerve sliding was significantly decreased in group A and group B. Conclusions: The HRUS might be useful for the evaluation of carpal tunnel syndrome. The decrease in mobility of the median nerve in the carpal tunnel might be a predisposing factor of carpal tunnel syndrome.