Ultrasonographic and Electrophysiological Evaluation of the Ulnar Nerve in Patients Diagnosed With Carpal Tunnel Syndrome.

PURPOSE: In this study, we evaluated the ulnar nerve of patients diagnosed with carpal tunnel syndrome (CTS) using electrophysiology and ultrasonography.

METHODS: The study included 86 patients (136 hands) and 39 controls (78 hands) with normal electrophysiological assessment. According to Bland's classification, patients were divided into group 1 (grades 1-3 CTS) or group 2 (grades 4-6 CTS). The ulnar nerve was evaluated at the wrist using nerve conduction studies and ultrasonography.

RESULTS: The sensory velocity was slower in group 2 than in group 1 (P < 0.001), slower in group 2 than in controls (P < 0.001), and slower in group 1 than in controls (P < 0.005). Although the ultrasonography results showed a reduction in the ulnar nerve cross-sectional area in group 1 compared with controls, the difference was not statistically significant. However, the reduction was significant in group 2 compared with group 1 and controls (P < 0.001).

CONCLUSIONS: Based on our study results, the ulnar nerve is affected electrophysiologically and morphologically in patients with CTS, especially those with advanced-stage CTS.