Physical examination has a low yield in screening for carpal tunnel syndrome

Abstract

Background: physical examination is often used to screen workers for carpal tunnel syndrome (CTS). In a population of newly hired workers, we evaluated the yield of such screening.

Methods: our study population included 1,108 newly hired workers in diverse industries. Baseline data included a symptom questionnaire, physical exam, and bilateral nerve conduction testing of the median and ulnar nerves; individual results were not shared with the employer. We tested three outcomes: symptoms of CTS, abnormal median nerve conduction, and a case definition of CTS that required both symptoms and median neuropathy.

Results: of the exam measures used, only Semmes-Weinstein sensory testing had a sensitivity value above 31%. Positive predictive values were low, and likelihood ratios were all under 5.0 for positive testing and over 0.2 for negative testing.

Conclusion: physical examination maneuvers have a low yield for the diagnosis of CTS in workplace surveillance programs and in post-offer, pre-placement screening programs.

Figure 1

Frequency of positive physical exam findings for three tests of the right and left hands

Figure 2

Frequency of overlap of positive symptoms, physical exam results and abnormal nerve conduction studies of the right and left hands