Diagnosing a high ankle sprain. Because syndesmotic sprains can be associated with lateral ligament injuries, medial ligament injuries, and fractures of the fibula, x-rays of the lower leg and ankle are necessary. If the athlete has a total syndesmosis rupture, separation will be evident in the x-ray between the tibia, fibula, and talus.
A sprained ankle can occur on the lateral side of the ankle (most common), the medial side of the ankle (least common) or can occur as a syndesmotic sprain when the ligaments between the distal tibia and fibula are injured, also known as a high ankle sprain.
High ankle sprain: The ligament joining the two bones of the lower leg (tibia and fibula), called the syndesmotic ligament, is injured. A high ankle sprain causes pain and swelling similar to a true ankle sprain, but can take longer to heal. Ankle fracture: A break in any of the three bones in the ankle.