E B Bodofsky1, W M Greenberg, K D Wu. 1. Department of Physical Medicine and Rehabilitation, Cooper Hospital/University Medical Center, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School at Camden, USA. bodofsky-elliot@cooperhealth.edu
Abstract
OBJECTIVE: Carpal Tunnel Syndrome (CTS) is commonly bilateral, but symptoms and EMG/NCS abnormalities may be seen unilaterally. This study was designed to determine whether there are any subclinical nerve conduction abnormalities on the "uninvolved" side. DESIGN: Statistical analysis of electrodiagnostic data. SETTING: Outpatient academic electrodiagnostic laboratory. PATIENTS: Twenty-two successive patients referred for bilateral upper extremity NCS/EMG with no symptoms or physical signs of CTS and totally normal results, and ten successive patients with an EMG/NCS diagnosis of CTS on one side, and completely normal EMG/NCS on the contralateral side. RESULTS: The median motor and sensory latencies at the wrist were significantly longer in the contralateral "uninvolved" limb than normals (median motor latency 3.75 vs. 3.30 msecs, p = 0.0005, median sensory latency 3.40 vs 3.00 msecs, p = 0.0002). Median sensory amplitude was smaller in the contralateral limb (30.5 uV vs. 41.5 uV, p = 0.0062). The (median-radial) D1 sensory latency difference was greater in the contralateral wrist (0.2 vs. 0.0 msecs, p = 0.0217). The (median-ulnar) sensory latency difference was not significantly increased (0.15 vs. 0.10 msecs, p = 0.2020). CONCLUSIONS: The contralateral limbs of patients with unilateral CTS show significant differences from normals in 4 out of 5 nerve conduction parameters. There is evidence of frequent subclinical median nerve compression in this group.
OBJECTIVE: Carpal Tunnel Syndrome (CTS) is commonly bilateral, but symptoms and EMG/NCS abnormalities may be seen unilaterally. This study was designed to determine whether there are any subclinical nerve conduction abnormalities on the "uninvolved" side. DESIGN: Statistical analysis of electrodiagnostic data. SETTING:Outpatient academic electrodiagnostic laboratory. PATIENTS: Twenty-two successive patients referred for bilateral upper extremity NCS/EMG with no symptoms or physical signs of CTS and totally normal results, and ten successive patients with an EMG/NCS diagnosis of CTS on one side, and completely normal EMG/NCS on the contralateral side. RESULTS: The median motor and sensory latencies at the wrist were significantly longer in the contralateral "uninvolved" limb than normals (median motor latency 3.75 vs. 3.30 msecs, p = 0.0005, median sensory latency 3.40 vs 3.00 msecs, p = 0.0002). Median sensory amplitude was smaller in the contralateral limb (30.5 uV vs. 41.5 uV, p = 0.0062). The (median-radial) D1 sensory latency difference was greater in the contralateral wrist (0.2 vs. 0.0 msecs, p = 0.0217). The (median-ulnar) sensory latency difference was not significantly increased (0.15 vs. 0.10 msecs, p = 0.2020). CONCLUSIONS: The contralateral limbs of patients with unilateral CTS show significant differences from normals in 4 out of 5 nerve conduction parameters. There is evidence of frequent subclinical median nerve compression in this group.
Authors: Cory Demino; Anne E Argenta; Gabriella Dibernardo; Kia Washington; Robert J Goitz; John R Fowler Journal: J Hand Surg Glob Online Date: 2020-07-11