High Ankle Sprains

What is a High Ankle Sprain?

A high ankle sprain, also called a syndesmotic sprain, involves injury to the syndesmotic ligaments. The syndesmotic ligaments are strong bands of tissue that connect the leg bones (tibia and fibula) together above the ankle joint, which is why this injury is called a high ankle sprain. 

These injuries are much less common than standard ankle sprains, comprising only 15% of all ankle sprains. 

The mechanism of injury is different than a lateral ankle sprain, which occurs with an inward twisting mechanism. High ankle sprains occur when the lower leg and foot externally rotates. They are common in sports such as skiing and football.

Symptoms of High Ankle Sprains

Symptoms may include:

• Difficulty bearing weight, standing or walking 
• Pain and swelling above the level of the ankle
• Tenderness at the syndesmotic ligaments above the ankle joint

Diagnosis of High Ankle Sprains

Specific exams for this injury include the squeeze test and external rotation test. Each of these is performed by the doctor, with the presence of pain at the syndesmosis indicating a high ankle sprain.

The physical exam may reveal other locations of tenderness and in some cases this injury is associated with an ankle or leg fracture.

Imaging studies may include:

• X-rays of the ankle and leg to check for fractures and alignment of the ankle
• A “stress” X-ray, in which the ankle joint is gently examined for stability
• MRI to check for ligament/tendon tears, bone bruising, cartilage injury
• CT to view bone details (fractures, relationship between tibia and fibula)  

It is important to determine if the high ankle sprain is stable. If the high ankle ligaments are torn and there is widening of the ankle syndesmosis or shifting of the bones, surgery is required to establish the correct alignment of the ankle to allow proper healing and function.  

Non-surgical Treatment for High Ankle Sprains

Early treatment involves Rest-Ice-Compression-Elevation therapy. Some patients require the support of a removable walking boot brace and crutches to minimize discomfort with early weight bearing.  

With stable high ankle sprains, non-surgical treatment is appropriate and physical therapy is initiated early. Recovery from a high ankle sprain takes considerably longer than a standard ankle sprain. 

For athletes, return to play can take 6 weeks and is often longer. Stiffness is a common and requires early and extensive rehabilitation.

Surgical Treatment for High Ankle Sprains

For individuals with unstable high ankle sprains, surgery is indicated. Separation of the tibia and fibula just above the ankle joint indicates the syndesmotic ligaments are completely torn and not providing stability.  

Surgery involves putting the tibia and fibula back together and supporting them with screws or newer fixation devices which have strong suture-type material. In many instances, the screws are later removed after the ligaments have sufficiently healed. 

Patients treated surgically are often kept non-weight bearing for the initial recovery period. It often takes athletes between three and six months to recover and resume running and sports after this type of surgery. In the case of delayed diagnosis or patients whose surgery has lost correction, revision surgery may become necessary.