Severe injuries can result in combined injury to the anterior talofibular ligament and the heel-fibular ligament (20-40% of cases), while the strong heel-fibular ligament is rarely involved, except in severe trauma of ankle dislocation. Isolated tears of the heel-fibular ligament are rare. Lateral ankle ligament injuries can be classified into 4 grades depending on the site of involvement: grade 1, strain or partial tear of the anterior talofibular ligament; grade 2, complete tear of the anterior talofibular ligament with the other ligaments intact; grade 3, complete tear of the anterior talofibular ligament with partial tear of the heel fibular ligament; grade 4, complete tear of both the anterior talofibular ligament and the heel fibular ligament. On ultrasonography, a partial tear of the ankle ligament shows swelling of the ligament and a limited or diffuse internal hypoechoic zone, while a complete tear shows the parenchyma of the ligament separated by a hypoechoic zone of hematoma and a wave-like retraction of the free end of the ruptured ligament (normal is linear). Rupture of the anterior talofibular ligament is often complicated by rupture of the joint capsule and spillage of joint fluid into the anterolateral soft tissues, whereas complete rupture of the heel-fibular ligament may result in traffic between the ankle joint cavity and the tendon sheath of the peroneal muscle. Rupture of the heel-fibular ligament rarely involves a tear of the supraspinatus support band of the peroneal muscle. Since the heel-fibular ligament normally tenses and pushes the peroneal tendon laterally during ankle dorsiflexion, this action can also be used to determine its integrity. In fact, the loss of displacement of the peroneal tendon during dorsiflexion is a sign of a complete tear of the heel-fibular ligament. Calcification is also seen within the injured ligament, often as avulsed bone fragments. During the sweep, pressure testing can help identify ligament injuries. These maneuvers should be performed carefully to avoid pain and reflex muscle contractions leading to false negative results. In complete tears of the anterior talofibular ligament, the anterior drawer motion test is easier to perform: the foot is placed on the edge of the examination bed and the forefoot is dragged forward in a plantarflexed and turned position. This method is useful in identifying partial tears (grade 2) and complete tears (grade 3) of the anterior talofibular ligament in difficult cases. In a complete tear, the anterior displacement of the talus relative to the tibia can open up the gap between the ligament rupture to make the lesion more clear, whereas the distance between the talus and tibia will remain the same in cases of partial tears. Lower tibiofibular joint injuries account for approximately 10% of ankle injuries. The cause of injury (valgus vs. valgus) is consistent with the cause of deltoid ligament tears, most often involving the anterior talofibular ligament Ultrasound can accurately assess anterior talofibular ligament tears. Tears of this ligament are often complicated by fibular fractures.