Ankle instability

Ankle instability

Foot and Ankle ​Condition

Ankle instability

Poor healing of the ankle ligaments, after a sprain, can lead to chronic ankle instability, which main features are persistent pain, recurrent sprains and a feeling of instability (repeated “giving out”) of the ankle.


Stability depends primarily on the position of the talus, when it is in extension (dorsal flexion) the ankle is more stable due to the great congruence of the articular surfaces. In plantar flexion the collateral ligaments are more important, since the talus is not fitted.

The external lateral ligament of the ankle is divided into three fascicles: anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL) and posterior talofibular ligament (PTFL).


Chronic ankle instability usually develops after an ankle sprain that has not healed properly or was not fully rehabilitated. When you suffer an ankle sprain, the connective tissues (ligaments) stretch or tear. The ability to stay in balance is often affected. Proper rehabilitation is required to strengthen the muscles around the ankle and “retrain” the tissues within the ankle that affect balance. Failure to do so may result in frequent ankle sprains.

Frequent ankle sprains often cause, and perpetuate, chronic ankle instability. Each subsequent sprain leads to further weakening (or stretching) of the ligaments, resulting in greater instability and likelihood of developing additional problems in the ankle joint.


Ankle instability initially presents with an insecure walk, which may be associated with pain and cracking noises under increased tension. In case of acute instabilities, p. ex.due to a torn ligament, swelling and discoloration will be seen in the affected area.


Non-surgical treatment may include:

  • Physical therapy
  • Orthotics
  • Medications
Surgical treatment

Surgical repair of chronically weak ankle ligaments can be done very successfully. Generally speaking, there are techniques that repair injured ligaments and others that create ligament grafts, removing them from the patient’s own tendons or from a donor. It is important to mention that an acute rupture of the ligaments is usually treated conservatively and surgery is reserved for chronic injuries, when non-surgical treatment has failed (at least 3 months of treatment without results).

These procedures are usually very successful, because people are able to return to all their activities, including sports, without risk of recurrent ankle injury.