DIAGNOSTIC VALUE OF MEDIAN NERVE CONDUCTION VELOCITY ACROSS WRIST AMONG PATIENTS WITH SUSPECTED CARPAL TUNNEL SYNDROME

Abstract

Background: Carpal Tunnel Syndrome (CTS) is the most prevalent type of compressive neuropathy. At present, electrodiagnosis is considered the gold standard in diagnosing CTS. However, no clear cutoff point has been established regarding the diagnostic value of the median nerve conduction velocity, across the carpal tunnel area, among patients with CTS.
 Objectives: This study aimed to determine the cutoff point for patients’ median nerve conduction velocity (NCV), to diagnose CTS among suspected patients, which is determined using electrical stimulations conducted across the carpal tunnel area. The present study also aimed to determine the diagnostic value of the median nerve conduction velocity across the carpal tunnel area, compared with the standard method.
 Methods: This cross-sectional study was conducted among 56 participants (106 wrists) suspected of CTS. Motor and sensory NCV across the carpal tunnel was investigated to yield diagnostic value of CTS compared with the standard technique.
 Results: The optimal cutoff point in diagnosing CTS using the wrist to midpalm conduction velocity, was 40 m/s (with a sensitivity of 87.04% and specificity of 87.18%) for the sensory nerve conduction study, and 35 m/s (with a sensitivity of 88.06% and specificity of 89.74%) for the motor nerve conduction study.
 Conclusion: Our study determined that the optimal cutoff conduction velocities for CTS diagnosis, using the wrist-to-midpalm electrical stimulation method, was 40 m/s for the sensory nerve, and 35 m/s for the motor nerve.