Diagnostic value of knee extension torque tracings in suspected anterior cruciate ligament tears.

The purpose of this study was to determine the diagnostic accuracy of knee extensor muscle torque tracings in patients suspected of having damage to the anterior cruciate ligament of the knee joint. The knee extensor torque tracings of 30 patients suspected of having anterior instability of the knee joint were reviewed independently for abnormalities believed to be associated with anterior cruciate ligament damage. These results were compared blindly with an arthroscopic evaluation. The diagnostic accuracy of the torque tracing approach was determined by calculating the prevalence, sensitivity, specificity, and positive and negative predictive values. The sensitivity and specificity were calculated to be 25.0% and 85.7%, respectively. These results suggest that the curve patterns examined in this article have poor diagnostic accuracy and are of little benefit as a clinical diagnostic aid.