OBJECTIVE: Analyze the ultrasonographic findings of normal and injured anterolateral ligament.METHODS: The anterolateral ligaments of 20 patients with acute unilateral anterior cruciate ligament(ACL)injuries,as diagnosed by MRI,were examined by ultrasonography and MRI.The injuries were evaluated after obtaining high-resolution images.The Cohen's Kappa coefficient was used to evaluate consistency between observers.The threshold of thickness for ALL injury was obtained by receiver operating characteristic(ROC)curve.RESULTS: In knee joints with ACL injury,the incidence of ALL injury,as diagnosed by ultrasound,was 45%(9/20,k = 0.80),including nine cases with insertion tibial plateau injuries(k = 1)and two cases with lateral condyle of the femur attachment injuries(k = 0.79).The results of ROC curve analysis showed that a lateral femoral condyle attachment ALL thicker than 0.65 mm under ultrasound was considered to be an injury(sensitivity: 100%,specificity: 40%),whereas an tibial plateau insertionALL thicker than 1.25 mm was considered to be an injury(sensitivity: 88%,specificity: 93%).CONCLUSION: ALL injury was often accompanied by an ACL tear,and the injury usually occurred at the insertion of the tibial plateau.Ultrasound is a simple and rapid method for the examination of ALL. |