Evaluation of electrophysiological examinations for the diagnosis of carpal tunnel syndrome.

To investigate the clinical significance of results in electrodiagnostic evaluations for carpal tunnel syndrome(CTS) and analyze the correlation between electrodiagnostic evaluations and physical examinations, 236 CTS patients and 96 healthy volunteers accepted electrodiagnostic evaluations. There were significant differences between CTS and control groups, mild and moderate patients, moderate and severe patients in CTS groups respectively, in terms of compound muscle action potential(CMAP), sensory conduction velocity of middle finger(SCV), distal motor latency(DML) difference between median nerve and ulnar nerve on the ring finger(△DML) (p < 0.05).△DML has larger area under curve of ROC curve (0.974) than CMAP, SCV and DML(0.748, 0.950, 0.958), then △DML could be included as valuable test for diagnosing and classification of carpal tunnel syndromes. There was low correlation between electrodiagnostic evaluations and physical examinations (rho < 0.4), so electrodiagnostic evaluation and physical examination should be combined to diagnose CTS. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic III.