High Ankle Sprain
High ankle ligaments are those that are located above (closer to the knee with respect to the ankle) than the more commonly injured ligaments on the outside of the ankle. These high ankle ligaments connect the tibia to the fibula. It is important to have stability between the tibia and fibula at this level because there is a tremendous amount of force that passes through this junction when walking and running. Some rotation of the fibula with respect to the tibia is permitted by these ligaments. A high ankle sprain occurs when there is tearing and damage to the high ankle ligaments. These injuries are much less common than a traditional ankle sprain.
Symptoms and Clinical Presentation
A high ankle sprain occurs from a twisting or rotational injury. The high ankle sprain also can occur in the setting of an ankle fracture, which means the bones of the ankle are broken. In some cases, the ligament on the inside of the ankle, the deltoid, will be torn. In this event, the energy of the injury passes from the deltoid, through the high ankle ligaments, or syndesmosis, and up the leg through the fibula. This causes the fibula to be broken at a very high level. This type of fracture is called a Maisonneuve fracture. Patients with a high ankle sprain without fracture may be able to bear weight but will have pain over the junction between the tibia and fibula just above the level of the ankle. This is higher than the more traditional sprains.
Cause (including risk factors)
High ankle sprains occur from rotational injuries, much like ankle fractures. They are common in sports, especially impact sports. An external rotation, meaning that the foot is turned towards the outside with respect to the leg, most commonly causes these tears.
Patients who have a high ankle ligament tear usually will have pain just above the level of the ankle. They may also have tenderness over the deltoid ligament if they have a Maisonneuve injury, as noted above. It is important to touch the area to assess whether pain is just around the lateral ankle ligaments or higher. Two important tests also include the “squeeze test” and the "external rotation test.”
The squeeze test is performed by squeezing the leg just below the knee to see if pain radiates to the high ankle ligament area, which would suggest a high ankle sprain. With the external rotation test, the knee is bent and the ankle is placed in neutral, or 90 degrees with the foot in relation to the leg, and the foot is turned to the outside. If there is pain at the syndesmosis or the high ankle ligament area, then this indicates injury.
X-rays are very important. A broken bone must be assessed and ruled out. Three views of the ankle, including the whole leg are important. A fracture on the back portion of the tibia may indicate an injury to the high ankle ligaments, given that this is where the PITFL attaches. It is also important to look for increased space between the tibia and the fibula because this may also indicate an injury to the high ankle ligaments, which has allowed the two bones to separate. MRI is becoming very helpful in diagnosing these injuries. When a high ankle sprain is suspected, it may be very helpful. A CT scan can also help to assess the relationship of the tibia with the fibula.
Frequently Asked Questions
Should I be concerned if I have sprained my ankle and it is not better after six weeks?
Yes. Most ligaments will heal after six weeks. It is probably worth seeing your doctor to assess if any other injuries have occurred. Sometimes high ankle sprains can take that long or longer, but it is wise to make sure that another injury has not occurred.
Can I tear both the high ankle ligaments and the low ankle ligaments?
It is rare to have such an injury since the force is generally dissipated through one area or the other. However, there are unique cases where both are torn.
*Source: American Orthopaedic Foot & Ankle Society® http://www.aofas.org