Ultrasound can accurately diagnose carpal tunnel

(HealthDay)—Ultrasound can accurately confirm the diagnosis of carpal tunnel syndrome, according to a study published in the Sept. 3 issue of The Journal of Bone & Joint Surgery.

John R. Fowler, M.D., from the University of Pittsburgh, and colleagues compared the sensitivity and specificity of ultrasound and electrodiagnostic testing for diagnosing carpal tunnel syndrome in a series of 85 patients. All patients were assessed with the Carpal Tunnel Syndrome 6 (CTS-6) clinical diagnostic tool, which was used as the reference standard.

The researchers found that ultrasound had a sensitivity of 89 percent and specificity of 90 percent, while electrodiagnostic testing had a sensitivity of 89 percent and specificity of 80 percent. The positive predictive values were 94 and 89 percent, respectively, for ultrasound and electrodiagnostic testing, while the negative predictive values were 82 and 80 percent, respectively. Ultrasound was accurate in 89 percent of cases and electrodiagnostic testing was accurate in 86 percent of cases.

"While ultrasound will not replace electrodiagnostic testing in complicated or unclear cases, in a select group of patients with a positive CTS-6, ultrasound can be used to confirm the diagnosis of carpal tunnel syndrome with better specificity and equal sensitivity as compared with those of electrodiagnostic testing," the authors write.