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Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies
Published on: January 11, 2019
Wrist squareness and median nerve impairment
R C Sposato1, M W Riley, J L Ballard
1Department of Industrial and Management Systems Engineering, University of Nebraska-Lincoln 68588-0518, USA.
Journal of Occupational and Environmental Medicine
|September 1, 1995
Summary
Wrist squareness ratio is not a reliable predictor of carpal tunnel syndrome (CTS) in railroad workers. This study found no correlation between wrist shape and median nerve impairment, challenging previous research findings.
Area of Science:
- Occupational Health
- Neurology
- Biomedical Engineering
Background:
- Previous research suggested a wrist-squareness ratio > 0.7 predicts median nerve sensory latency > 3.7 ms.
- This latency is often associated with carpal tunnel syndrome (CTS).
Purpose of the Study:
- To investigate the utility of wrist squareness as a predictor of median nerve impairment in railroad maintenance workers.
- To validate or refute previous findings in a specific occupational cohort.
Main Methods:
- Measured wrist thickness and width in 417 railroad maintenance workers.
- Calculated wrist-squareness ratios for each participant.
- Performed electrodiagnostic testing on median nerve motor and sensory fibers per American Academy of Electrodiagnostics Medicine guidelines.
Main Results:
- Wrist squareness was not found to be a useful predictor of median nerve impairment.
- The study did not support the hypothesis that wrist squareness predicts carpal tunnel syndrome in this population.
Conclusions:
- Wrist squareness is not a reliable diagnostic indicator for carpal tunnel syndrome in railroad maintenance workers.
- Further research may be needed to identify specific occupational risk factors for CTS in this group.
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