The ankle joint is an extremely stable joint. It functions as a hinge joint and must be able to bear 1.5 to 8 times the body's weight, according to eOrthopod. The ankle joint is formed by the ends of the two legs bones, the tibia and fibula, which form a socket for the talus bone of the foot. The joint is held together by a number of ligaments, which attach one bone to another. It is possible to injure those ligaments during an ankle sprain.
The ankle joint is a complex structure and an ankle sprain is the most common joint injury. According to HealthCentral.com, of the 1 million ankle joint injuries suffered by people per year, 85 percent are ankle sprains. An ankle sprain occurs when the ligaments of the joint are stretched and possibly torn, typically due to the ankle "twisting" or "tuning over." Ankle sprains are more likely to occur during sports play that feature side-to-side motion, such as tennis or basketball, but can occur at any time during weight-bearing, including walking.
Types and Causes
According to MayoClinic.com, an ankle sprain is caused by over-stretching or tearing a ligament while the joint is under stress. An inversion sprain is caused when the ankle rolls out and the foot is turned under. Cigna states this is the most common type of ankle sprain, and it causes the ligaments on the outside of the ankle to stretch and tear. An eversion sprain occurs when the ankle turns inward while the foot turns outward, injuring the ligaments on the inside of the ankle. When a ligament is torn during an ankle sprain, an audible popping noise may be heard.
The symptoms of a severe ankle sprain include pain, bruising and swelling, which typically appear immediately after suffering the sprain. There may be an inability to move the joint or bear weight on the affected side. HealthCentral.com warns that if a popping sound is heard immediately following the injury, it can be a sign that a ligament has been ruptured or torn. This popping sound is indicative of a severe sprain, which may also include a fracture and requires examination by a health care professional.
Severe sprains that include an over-stretched or torn ligament require medical attention and treatment. An x-ray can determine the presence of a fracture, and an MRI can determine the location and severity of torn ligaments. Cigna states a cast or brace may be needed for 4 to 6 weeks while the sprain heals. Non-steroidal anti-inflammatory medication, such as ibuprofen, can alleviate pain and swelling. If the sprain is severe, crutches may be used to limit weight-bearing. Surgery may be required to repair torn ligaments.
Following treatment, physical therapy for strengthening the ankle may be prescribed. MedlinePlus recommends losing weight, avoiding high heels and platform shoes and stretching before exercising or playing sports. If there is a tendency towards twisting the ankle, wearing orthotics to balance the foot or an ankle brace to stabilize the ankle may help prevent sprains.