Diagnostic strategies using physical examination are minimally useful in defining carpal tunnel syndrome in population-based research studies.
Descatha-A; Dale-AM; Franzblau-A; Coomes-J; Evanoff-B
Occup Environ Med 2010 Feb; 67(2):133-135
OBJECTIVE: We evaluated the utility of physical examination manoeuvres 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 manoeuvres 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 <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.
Ergonomics; Epidemiology; Exposure-assessment; Exposure-levels; Exposure-methods; Injuries; Injury-prevention; Musculoskeletal-system-disorders; Occupational-exposure; Occupational-hazards; Questionnaires; Statistical-analysis; Work-analysis; Worker-health; Work-performance; Workplace-studies; Work-practices
Dr Alexis Descatha, Unité de pathologie professionnelle, CHU Poincaré, 104 bd R. Poincaré, 92380 Garches, France
Occupational and Environmental Medicine
Washington University - St. Louis, Missouri