Ultrasonography of capsular morphology in normal and traumatic ankle joints.

Ultrasonography was used to inspect the ankle anatomy of 20 healthy volunteers. The images produced were correlated with anatomical structures by examining three dissected cadaver ankles. The anterolateral pouch of the articular capsule was identified by ultrasonography in 91% of the normal ankle joints as a hypoechoic area. The posterolateral pouch of the articular capsule also could be identified by ultrasonography as a hypoechoic area in 84% of the normal ankles examined. The lateral aspect of 105 traumatized ankles was examined subsequently. The ultrasound results agreed in 100% of the cases with the operative findings for the anterior talofibular ligament and in 92% for the calcaneofibular ligament.