The bones, ligaments, and tendons in the ankle joint are meant to work together to provide optimal stability.
However, if any of these parts becomes compromised in some way, the result may be chronic ankle instability. Also, because of the way the tibia (shinbone) and fibula (calf bone), a chronically unstable ankle could result in a lower leg fracture or related soft tissue problems.
Treatment will depend on what’s causing the instability and the extent of the damage.
Symptoms and Causes
One of the first signs of chronic ankle instability is a giving way sensation along the outer side portion of the ankle. The condition often develops after a series of repeated ankle sprains. When an ankle is already weakened from sprains, it may suddenly way while playing sports, jogging, running, or even when walking. It’s not a condition that should be ignored, especially since there’s research linking untreated ankle sprains and instability with osteoarthritis.
Age-related wear affecting tendons and ligaments sometimes contributes to recurring instability of one or both ankles. Some other chronic ankle instability contributing factors are tendonitis, having a split in the peroneus brevis tendon, and poor or insufficient rehabilitation following an ankle sprain. Additionally, each subsequent sprain after the initial one further weakens ligaments within the ankle. Symptoms experienced may also include:
- Tenderness or pain in the affected ankle
- Ongoing or recurring discomfort
- Persistent swelling or inflammation
- Recurring ankle turning with foot movements
- Inability to bear any significant weight on the affected foot
Chronic Ankle Instability Diagnosis
Since chronic ankle instability is related to prior ankle sprains, diagnosis usually involves a discussion of previous ankle injuries. The affected ankle is then examined to look for tenderness and other signs of instability. X-rays and other image tests are typically performed as well to determine the extent of the damage. MRI and CT scans provide additional soft tissue details that can’t be detected with an X-ray alone.
Non-Surgical Treatment Options
With chronic ankle instability that’s mild or moderate, non-surgical treatment options are usually recommended before surgery is discussed. Ibuprofen, naproxen, and other non-steroidal anti-inflammatory drugs (NSAIDs) may ease tissue swelling enough to allow the affected ankle to heal. If the ankle is involuntarily turning, an ankle brace may be worn to support the ankle and keep it stable. Bracing may also reduce the risk of sustaining additional sprains.
Some sufferers of chronic ankle instability experience relief from a combination of various physical therapy techniques and methods. PT efforts specifically for the purpose of restoring ankle stability may involve:
- Range of motion exercises
- Isokinetic muscle strengthening
- Gentle ankle stretches
- Balance training
If instability of an ankle is severe or if non-surgical options aren’t effective, surgery may be necessary. The specific procedure performed will depend on what structures are damaged, although surgery for chronic ankle instability usually involves the reconstruction or repair of ligaments. With anatomic reconstruction, stretched or torn ligaments are repaired. A band of fibrous tissue called the retinaculum may also be tightened to maintain proper ankle alignment. With a peroneal substitution ligament reconstruction, the entire ligament is replaced.