An ankle sprain is the stretching or tearing of the ligaments that surround the ankle and provide stability to the ankle joint. Ligaments are structures that connect bones together and restrict motion.
Ankle sprains can vary in severity. Some sprains are mild and healing occurs in a matter of days. Some sprains are severe and require many weeks to heal. Severity is often referred to as grade.
Grade I sprain: Minimal damage
Grade II sprain: Moderate damage with some laxity
Grade III sprain: Complete tearing with significant laxity
Most ankle sprains are caused by inversion injuries (rolling the ankle). The ankle ligaments are then stretched and may even tear depending on the force placed upon them. Typically, the ligaments on the outside (lateral) of the ankle are damaged as the foot rolls inward. This is why most of the pain from an ankle injury is typically on the outside of the ankle. Some ankle sprains cause tearing of the connection between the leg bones (tibia and fibula) and this is called a “high ankle sprain”
Symptoms from an ankle sprain include pain, swelling, and bruising. If severe, ankle sprains can occasionally result in residual laxity (looseness). The blue discoloration that often occurs after sprains is due to blood from the damaged ligaments
Diagnosis of an ankle sprain is typically done by physical examination. Sometimes, x-rays are needed to evaluate for fracture. Occasionally, an MRI is ordered to evaluate for other injuries in the ankle.
Treatment is tailored to control swelling, decrease pain, improve comfort as healing occurs, and ultimately, to regain function. RICE therapy is the mainstay of treatment for most sprains.
Rarely, surgery is necessary to address an associated injury such as residual laxity or cartilage injury.
Recovery varies from days to weeks and is dependant upon the damage to ankle ligaments. Physical therapy, either at home or at a physical therapy center, can be helpful to regain full strength, motion, and function of an injured ankle.