Median and ulnar nerve conduction studies at the wrist: criterion validity of the NC-stat automated device.
Armstrong-TN; Dale-AM; Al-Lozi-MT; Franzblau-A; Evanoff-BA
J Occup Environ Med 2008 Jul; 50(7):758-764
Objective: To compare results obtained with the NC-stat - an automated nerve testing device - to traditional nerve conduction studies relevant to carpal tunnel syndrome screening. Methods: Thirty-three subjects recruited from patients referred for electrodiagnostic testing were studied. Measurements including the distal motor latency (DML), distal sensory latency (DSL), and median-ulnar latency difference (MUD) were obtained by the NC-stat and by standard nerve conduction studies. Results: With modifications to the NC-stat's suggested reference ranges, sensitivity with respect to the traditional results ranged from 93.8% (sensory MUD) to 100% (median DML and DSL) and specificity ranged from 84.6% (motor MUD) to 94.1% (sensory MUD). Sensitivity was as high or higher and specificity was lower when using the manufacturer's suggested cutoffs. Conclusion: The NC-stat appears to be a convenient and sensitive method for detecting median nerve pathology at the wrist.
Carpal-tunnel-syndrome; Hand-injuries; Nerve-damage; Nerve-function; Nerves; Testing-equipment; Humans; Men; Women; Neuropathology; Sensitivity testing
Bradley A. Evanoff, Washington University in St. Louis School of Medicine, Division of General Medical Sciences, Campus Box 8005, 660 S Euclid Avenue, St. Louis, MO 63110
Journal of Occupational and Environmental Medicine
Washington University - St. Louis, Missouri