anterior talofibular and calcaneofibular ligaments

Ankle sprains are classified both by grade and by type. Sprains are graded according to the level of ligamentous damage.

• Grade I being stretching and microscopic tearing of fibers and mild swelling.
• Grade II is partial tearing, moderate to severe swelling and mild instability.
• Grade III is complete rupture of the ligament with joint instability and inability to bear weight.

The type of ankle sprain depends on what ligament or ligaments are involved.

• Type I involves injury to the anterior talofibular ligament.
• Type II involves the anterior talofibular and the calcaneofibular ligaments.
• Type III involves the anterior talofibular, calcaneofibular and posterior talofibular ligaments.