An ankle sprain is an injury to the supporting ligaments of the ankle joint. It is best to go to an emergency hospital to have x-rays taken to rule out a fracture. Injuries to the anterior talofibular ligament are most common, followed by injuries to the Achilles fibular ligament. They are categorized as 1st, 2nd, or 3rd degree depending on the degree (microtear, partial tear, and full tear). If not treated properly, it can cause ankle instability, resulting in recurrent ankle sprains, exfoliation osteochondritis or delayed arthritis. Symptoms Swelling, pain, ecchymosis, and difficulty with weight bearing in the ankle. Physical Examination Pressure pain anterior or inferior to the outer ankle; increased pain with passive inversion or plantarflexion of the ankle; normal range of motion of the ankle; ankle instability in chronic patients. Treatment The goal is to reattach the ankle ligaments to the bone attachment points, strengthen the muscles, and prevent re-sprains. Limited weightbearing and braking of the ankle and lower leg or both treat acute ankle sprains. Acute phase Ice and elevation of the affected limb. Rehabilitation Restore normal joint range of motion and strengthen the ankle with exercises. Prognosis Patients whose injuries have not healed within 4-6 weeks should undergo stress radiographs for joint instability and MRI for exfoliative osteochondritis and occult fractures.