Comprehensive Osteopathic Medical Licensing Examination (COMLEX USA) Practice

Which ligament is typically injured in an eversion ankle sprain?

1. Deltoid ligament

2. ATF ligament

3. CF ligament

4. PTF ligament

The correct answer is: Deltoid ligament

In an eversion ankle sprain, the deltoid ligament is typically injured. This ligament is a complex of ligaments found on the medial side of the ankle and is crucial for stabilizing the joint. When the ankle undergoes an eversion injury, the foot rolls outward, placing stress on the ligaments on the inside of the ankle joint. The deltoid ligament, being the primary stabilizing structure on the medial side, is most susceptible to injury during this movement due to the excessive force that is applied when the ankle is forced outward. The other ligaments mentioned, such as the ATF (anterior talofibular) ligament, CF (calcaneofibular) ligament, and PTF (posterior talofibular) ligament, are located on the lateral side of the ankle. These ligaments are more commonly injured during inversion ankle sprains, where the foot rolls inward, typically resulting in a sprain of the lateral ligament complex rather than the deltoid ligament. Thus, in the case of an eversion ankle sprain, targeting the deltoid ligament is the most relevant and accurate identification of the structure at risk.