A high ankle sprain injures the large ligament above the ankle that joins together the two bones of the lower leg. These two bones, the tibia (shin bone) and fibula, run from the knee down to the ankle. They are joined together by this ligament called the "syndesmosis" or "sydesmotic ligament."
Symptoms of a High Ankle SprainA high ankle sprain causes symptoms similar to other ankle sprains, but patients often complain of pain when the ankle is externally rotated (turned to the outside) or when the calf is squeezed. This later finding, the so-called "squeeze test," is the classic test for syndesmotic injuries, but it is not very reliable for diagnosis.
How is a high ankle sprain diagnosed?
When a syndesmotic injury is suspected, your doctor can obtain special x-ray studies of the ankle called stress views. The ankle will usually look normal on routine x-rays even with a syndesmotic injury, but when the ligament is stressed, there may be abnormal alignment of the ankle joint depending on the severity of the injury. Tests such as a CT scan or MRI can also be used to assess a high ankle sprain, although they are not routinely needed.
Treatment of a High Ankle SprainSyndesmotic injuries tend not to heal as well as more common ankle sprains, that is why trainers and coaches of athletes are often concerned about "high ankle sprains." Your orthopedic doctor will first determine if the injury is stable or unstable. If the injury is stable, then the high ankle sprain can be treated in a cast, usually for a period of 6 weeks.
If the injury is unstable, then a surgery may be needed to stabilize the ankle. Your surgeon will place a screw between the tibia and fibula to hold the bones in proper position while the syndesmotic ligament heals. The are several methods of fixation of syndesmotic injuries, all with potential risks and benefits. It is a relatively safe and well-tolerated surgical procedure.