Physical Examination is Minimally Useful in Defining Carpal Tunnel Syndrome in Population Based Studies
- 1 UVSQ, AP-HP, France;
- 2 Washington University School of Medicine, United States;
- 3 University of Michigan School of Public Health, United States
- Correspondence to: alexis descatha, Occupational Health Department, UVSQ, AP-HP, Poincaré University Hospital, 104 bd Rayomond Poincaré, Garches, 92380, France; alexis.descatha{at}rpc.aphp.fr
- Received 7 April 2009
- Accepted 24 September 2009
- Published Online First 22 October 2009
Abstract
Objective: We evaluated the utility of physical examination maneuvers in the prediction of carpal tunnel syndrome (CTS) in a population-based research study.
Methods: We studied a cohort of 1108 newly employed workers in several industries. Each worker completed a symptom questionnaire, a structured physical examination, and nerve conduction study. For each hand, our CTS case definition required both median nerve conduction abnormality and symptoms classified as “classic” or “probable” on a hand diagram. We calculated the positive predictive values and likelihood ratios for physical examination maneuvers, in subjects with and without symptoms.
Results: The prevalence of CTS in our cohort was 1.2% for the right hand and 1.0% for the left hand. The likelihood ratios of a positive test for physical provocative tests ranged from 2.0 to 3.3, and those of a negative test from 0.3 to 0.9. The post-test probability of positive testing was less than 50% for all strategies tested.
Conclusion: Our study found that physical examination, alone or in combination with symptoms, was not predictive of CTS in a working population. We suggest using specific symptoms as a first level screening tool, and nerve conduction study as a confirmatory test, as a case definition strategy in research settings.
