When an ankle twists, turns, or rolls awkwardly, it can stretch or tear the ligaments that support the ankle. Commonly—as much as 90% of the time—an injury to ankle ligaments results from an inversion sprain. This is where the foot turns inward, and the ligaments on the outside of the ankle stretch beyond a typical range of motion.
The ligaments, a band of fibrous tissue connecting two bones for stability, on the outside of the ankle—the anterior talofibular ligament, the calcaneofibular ligament, and the posterior talofibular ligament—can all be injured at the same time. And each can stretch or tear to differing degrees than the others.
When the foot turns out, a medial ankle sprain can occur. The eversion injury, while far less common, impacts the deltoid ligament, which serves as the main stabilizer on the inside of the ankle.
Ankle sprain symptoms will vary based on the extent of the injury. Less severe ligament strains and tears may only cause tenderness and mild pain when walking. More intense injuries can result in pain when resting, and that intensifies with ankle use. Other symptoms include increased tenderness, bruising, and swelling. Ankle range of motion and stability can be hampered with an ankle sprain.
Athletes may report hearing or feeling a popping sound at the time of the injury, consistent with more severe ankle sprains.
Ankle sprains are classified into three grades. Each grade accounts for the severity of stretched and torn ligaments. Often the severity of symptoms is tied to the grade of injury.
A grade 1 ankle sprain is the mildest of the three grades. It occurs when the ligament has been slightly stretched with no tears. A grade 1 sprain often includes only mild pain, swelling, tenderness, and bruising around the ankle. The injured person can still easily bear weight and remain stable on their feet.
A grade 2 ankle sprain usually results from a partial tear of the ligament. Grade 2 sprained ankle symptoms include pain, bruising, tenderness, and swelling. A grade 2 ankle sprain may also make it difficult for a patient to bear weight on their ankle without pain. Stability could be compromised.
A complete tear or rupture of the ligament defines a grade 3 ankle sprain. Along with severe pain, tenderness, bruising, and swelling of the ankle area, bearing weight often becomes quite difficult. Stability is often severely impacted by the lack of ligament strength.
A high ankle sprain vs. low ankle sprain refers to not only the ligaments involved but the movement of the ankle that caused the injury. A high ankle sprain is an external rotation injury that injures the connection of the fibula and tibia bone in your ankle (syndesmosis). It can occur during athletic activity particularly when the ankle gets caught and the body twists around the ankle. This injury can often also hurt near the knee joint.
An ankle sprain can occur in any athletic activity involving cutting, jumping, or running on uneven surfaces. Common causes of an ankle injury during athletic activity:
Once an athlete sprains an ankle, it increases the likelihood of injuring it again. If not left to heal properly, the ankle injury can further damage the area around the ligaments, such as the bones and cartilage. If an athlete attempts to return to activity before the sprain has fully healed and stability has been restored, the risk for further injury increases. Even if the ankle is allowed to fully recover, the risk of re-injury remains high.
In addition to athletic movements and the quality of the surface an athlete competes on, being in poor physical condition or wearing improper shoes can increase the risk of an ankle injury. A lack of strength or flexibility in the ankle can also increase risk. The wrong shoes, whether ill-fitting or not designed for the activity or surface, makes an athlete more likely to sprain an ankle.
A doctor can diagnose an ankle sprain with both a physical examination and imaging technology.
A physical examination to diagnose an ankle sprain will often include:
If the ankle sprain is severe, your doctor may order an X-ray to rule out a bone fracture and confirm whether the ankle is sprained or broken. Sometimes, a magnetic resonance imaging (MRI) scan is needed to evaluate possible injuries to cartilage and tendons surrounding the ankle.
Treating an ankle sprain includes a mix of rest and restoration of the ligament's range of motion.
Typically, the RICE approach—rest, ice, compression, and elevation—is advised in the first 24 hours following an injury to reduce swelling and protect the ligaments from further damage. Ice, elevation, and compression will help reduce swelling. Rest can ensure no further damage happens to the ankle.
Sprained ankle treatment commonly includes range-of-motion exercises, often as soon as 24 hours following the injury. Small stretching exercises are typically done while seated without placing weight on the ankle, allowing the patient to test pain levels as exercises progress.
In more severe sprains, immobilization of the ankle during walking can help protect the ligaments. Physical therapy may be needed for ankle sprains that need more time to recover or have been immobilized.
During recovery, patients will focus on range-of-motion exercises, isometric strengthening, and balance.
As athletes return to activity, they should limit cutting and jumping, instead focusing on running on flat surfaces. For those returning to physical activity before the ankle completely heals, bracing or taping may provide additional stability to the ankle. Learn more about how ankle taping reduces risk of injury.
In rare cases of a full tear of multiple ligaments, a surgical option may allow an athlete to return to activity sooner than with rehabilitation.
A grade 1 sprain can take one to three weeks for recovery, while a grade 2 can take three to six weeks, and a grade 3 or a high ankle sprain recovery can last several months.
A strong ankle and proper warm-up can help limit the risk of ankle sprains. Tips for ankle sprain prevention include:
A grade 1 sprained ankle can heal in about one to three weeks, but it can take several months for a grade 3 or high ankle sprain to fully recover.
A grade 1 sprain may still allow a patient to walk without pain or instability, but typically a grade 2 or grade 3 sprain will lead to pain and instability during any weight-bearing activity. During recovery, rest is advised for at least 24 hours following an injury, but exercises may start soon thereafter.
If an acute injury occurs and the patient hears or feels a popping sound, it could signal a sprained ankle. Even without this sensation, if swelling, bruising, tenderness, pain, and instability occur following an injury, the ankle could be sprained.
For the first 24 hours, practice RICE—rest, ice, compression, and elevation—but following that, range-of-motion exercise will help strengthen the ligaments. Improving balance and ankle strength will offer the best chance of a full recovery.
A compression wrap is designed to support an ankle to prevent further injury during the day, so doctors advise leaving an ankle unwrapped while sleeping.
Both an ankle sprain and a broken ankle can have similar symptoms, but there are key differences to look for. Both injuries hurt, but a broken ankle may also lead to numbness or tingling. If tenderness is felt directly over the ankle bone, instead of in the soft tissue, that could suggest a break. A badly broken ankle will also cause a misshapen bone. It is difficult to assess if an ankle is broken or sprained and this usually requires an x-ray to be sure.