Ultrasonographic-surgical correlation of ankle tendon tears

This study evaluates the accuracy of ultrasonography in detecting ankle tendon tears of the peroneal, posterior tibial, and flexor digitorum longus tendons based on operative findings and clinical follow-up. A prospective study was performed in 33 patients with clinically suspected tendon injury. Sixty-eight tendons were evaluated sonographically. The diagnosis of an intrasubstance tear was made when disruption of uniform tendon architecture by hypoechoic linear or globular clefts was observed. Criteria used to diagnose complete tendon rupture included discontinuity or gap within the tendon or complete nonvisualization of the tendon. Treatment decisions were based on a combination of clinical parameters and imaging studies. Twenty-six patients had the presence or absence of tear confirmed at surgery. Five patients had a final diagnosis based on clinical findings, and two were lost to follow-up. Of the 68 tendons evaluated sonographically, 54 were directly inspected at surgery; 20 were found to be torn and 34 were intact. Ultrasonography was able to identify all tears correctly with an accuracy of 93%, a sensitivity of 100%, and a specificity of 88%. The positive and negative predictive values were 83% and 100%, respectively. The combined accuracy, sensitivity, and specificity of ultrasonography in detecting tendon tears in all patients evaluated both surgically and by clinical follow-up were 94%, 100%, and 90%, respectively.