Fowler JR. J Bone Joint Surg Am. 2014. doi:10.2106/JBJS.M.01250.
Ultrasound can be used to confirm carpal tunnel syndrome diagnosis with better specificity and equal sensitivity in certain patients compared with electrodiagnostic testing, according to study results.
Researchers evaluated 85 patients referred to an upper-extremity practice for electrodiagnostic testing for any reason over a 3-month period. All of the patients were evaluated with the Carpal Tunnel Syndrome 6 (CTS-6) clinical diagnostic tool. The researchers classified a score of 12 or greater as positive for carpal tunnel syndrome.
CTS-6 score was used as the reference standard in calculating sensitivity, specificity and accuracy for ultrasound and electrodiagnostic testing.
Study results showed a sensitivity of 89% and a specificity of 90% with ultrasound and a sensitivity of 89% and a specificity of 80% with electrodiagnostic testing.
The researchers found a positive predictive value of 94% with ultrasound compared with 89% with electrodiagnostic testing, as well as a negative predictive value of 82% with ultrasound vs. 80% with electrodiagnostic testing.
Of the 85 cases, ultrasound was accurate in 89% of cases while electrodiagnostic testing was accurate in 86%, according to study results.
The researchers concluded that although use of ultrasound is helpful for diagnosis in certain patients with a positive CTS-6 score, it will not replace electrodiagnostic testing in complicated or unclear cases.
Disclosure: The authors have no relevant financial disclosures.
