gms | German Medical Science

Objectives: The aim of this study was to evaluate the effectiveness of two diagnostic tests routinely used for diagnosing carpal tunnel syndrome, ultrasonography and nerve conduction studies by comparing their accuracy based on surgical results, with the remission of paresthesia as the reference standard.

Methods: We enrolled 115 patients, all of the female gender with a high probability of a clinical diagnosis of carpal tunnel syndrome. All patients underwent ultrasonography and nerve conduction studies for a diagnosis and subsequent surgical treatment. As a primary outcome, the accuracy of the ultrasonography and nerve conduction studies diagnoses was measured by comparing their diagnoses compared with those determined by the surgical outcomes. Their accuracy was secondarily evaluated based on before and after scores of the Boston Carpal Tunnel Questionnaire.

Results: Overall, 104 patients (90.4%) were diagnosed with carpal tunnel syndrome by the surgical reference standard, 97 (84.3%) by nerve conduction studies, and 90 (78.3%) by ultrasonography. The concordance of nerve conduction studies and surgical treatment (p <0.001; kappa = 0.648) was superior to that of ultrasonography and surgical treatment (p <0.001; kappa = 0.423). The sensitivity and specificity of ultrasonography and nerve conduction studies were similar (p = 1.000 and p = 0.152, respectively: McNemar's test). The Boston Carpal tunnel Questionnaire scores were lower after surgery in patients diagnosed by both ultrasonography and nerve conduction studies (p <0.001and p <0.001, respectively: analysis of variance).

Conclusions: Ultrasonography and nerve conduction studies effectively diagnosed CTS with good sensitivity but were not effective enough to rule out a suspicion of CTS.