Surgeons' Recommendations for Neurodiagnostic Testing With High Pretest Probability of Idiopathic Median Neuropathy at the Carpal Tunnel

Purpose: The utility of electrodiagnostic tests (EDx) for patients with a high pretest probability of idiopathic median neuropathy at the carpal tunnel (IMNCT) based on characteristic symptoms and signs is debated. Decision-making and care strategies could be informed by a better understanding of factors associated with surgeon recommendations for electrodiagnostic testing. Methods: Ninety-one upper-extremity surgeons participated in an online, survey-based experiment. Participants viewed 7 vignettes of patients with carpal tunnel syndrome, with the following factors randomized in each vignette: patient age, gender, magnitude of incapability, symptom intensity and the presence of nocturnal symptoms, palmar abduction weakness, and positive provocative tests results. We sought patient and surgeon factors associated with ordering EDx and surgeon-rated comfort with performing carpal tunnel release (CTR) without EDx. Results: Surgeons recommended EDx for over half of the patient vignettes, with notable variation (median, 57%; interquartile range, 14–100), and felt relatively neutral, on average, offering CTR without EDx. Twenty-six (29%) out of 91 surgeons ordered EDx for all patient scenarios, and 18 surgeons (20%) did not order testing for any scenario. A lower likelihood of EDx was associated with older age and positive provocative tests results. Greater surgeon comfort offering CTR without EDx was associated with older patients, the presence of nocturnal symptoms, palmar abduction weakness, and positive provocative tests results. Conclusions: Upper-extremity surgeons are neutral regarding diagnosing IMNCT based on electrodiagnostic evidence of pathology and are relatively more comfortable offering surgery without EDx in older patients that present with key aspects of carpal tunnel syndrome. There is notable variation in care, with half of all surgeons always or never ordering EDx. Clinical relevance: Future studies can investigate whether a treatment strategy offering surgery to patients with a high pretest probability of IMNCT and only using EDx in intermediate probability scenarios can limit use of testing without affecting patient health.