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.