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Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies
Published on: January 11, 2019
Lack of utility of Semmes-Weinstein monofilament testing in suspected carpal tunnel syndrome
Keith J Pagel1, Matthew P Kaul, John D Dryden
1Rehabilitation Medicine Service, Department of Veterans Affairs Medical Center, Portland, Oregon 97207, USA.
Objective:
To investigate the value of Semmes-Weinstein monofilament (SWM) testing in patients with electrodiagnostically confirmed carpal tunnel syndrome in a group of patients with symptoms compatible with carpal tunnel syndrome.
Design:
A total of 119 consecutive patients with symptoms compatible with carpal tunnel syndrome were assessed. Blinded comparison of two Semmes-Weinstein monofilament testing protocols with orthodromic midpalm electrodiagnostic testing was performed. The electrodiagnostic test was considered the standard to which the results of the Semmes-Weinstein monofilament testing were measured.
Results:
Fifty three percent of our patients had electrodiagnostically confirmed carpal tunnel syndrome. Using a conservative Semmes-Weinstein monofilament testing protocol the sensitivity was 98% and the specificity was 15%. The positive predictive value was 56% and the negative predictive value was 88%. Using a liberal Semmes-Weinstein monofilament testing protocol the sensitivity was 13% and the specificity was 88%. The positive predictive value was 53% and the negative predictive value was 47%.
Conclusion:
Semmes-Weinstein monofilament testing was not shown to have utility in diagnosing electrodiagnostically confirmed carpal tunnel syndrome in our population of predominantly male veterans.
