Related Experiment Video
Updated: Aug 20, 2026
Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies
Published on: January 11, 2019
Sensitivity, specificity, and variability of nerve conduction velocity measurements in carpal tunnel syndrome
Henry L Lew1, Elaine S Date, Steven S Pan
1Physical Medicine and Rehabilitation Service, VA Palo Alto Health Care System, Palo Alto, CA 94304, USA. henrylew@stanford.edu
Objective:
To explore the diagnostic values of 8 commonly used electrodiagnostic techniques for measuring median nerve conduction velocity (NCV) in carpal tunnel syndrome (CTS).
Design:
Sensitivity and specificity analyses.
Setting:
A hospital-based electrodiagnostic laboratory.
Participants:
Forty-four normal hands and 136 symptomatic hands.
Interventions:
Not applicable.
Main Outcome Measures:
(1) Long-segment studies: antidromic wrist-to-digit sensory NCV without subtraction, (2) short-segment studies: transcarpal palm-to-wrist mixed NCV without subtraction, and (3) 2 segment studies: antidromic transcarpal sensory NCV with subtraction (differential calculation from wrist-to-digit and palm-to-digit segments). Both onset and peak latency values were obtained for calculating the NCV. Sensitivity, specificity, and coefficient of variance were calculated for each NCV study.
Results:
The short-segment, onset latency-based transcarpal mixed NCV yielded the highest sensitivity (75%).
Conclusions:
Results from measurement of a single, short-nerve segment tended to be superior to results obtained by either long-segment studies or differential subtraction between 2 segments of the same nerve in the electrodiagnosis of CTS. Explanations for our results are offered from both electrophysiologic and statistical perspectives.
