In a high ankle sprain, which ligament is injured?

• A. Anterior tibiofibular
• B. Anterior talofibular
• C. Calcaneofibular
• D. Deltoid

Answer: (A)

In a high ankle sprain, the injury targets the distal tibiofibular syndesmosis, not the usual lateral ligaments of the ankle. The front portion of this syndesmotic complex, the anterior tibiofibular ligament, is the primary structure stressed when an external rotation or dorsiflexion force drives the tibia and fibula apart at the top of the ankle. This is why the anterior tibiofibular ligament is the best answer: it specifically reinforces the joint between the tibia and fibula at the front and bears the brunt of syndesmotic stress in these injuries.

In contrast, the anterior talofibular and calcaneofibular ligaments are lateral stabilizers injured in typical inversion (low) ankle sprains, and the deltoid ligament is a medial stabilizer involved in eversion injuries. While other syndesmotic components (like the posterior tibiofibular ligament) can be involved, the anterior tibiofibular ligament is classically implicated in high ankle sprains.