What is chronic ankle instability?

There are different types of chronic ankle instability, but lateral ankle instability is the most common. It occurs after you have a lateral ankle sprain and injure the ligaments on the side of your ankle.

Ankle anatomy

There are two main ligaments on the side of your ankle: the anterior talofibular ligaments from the fibula, the skinny bone on the side of your ankle, to the talus, the first bone of your foot; and the calcaneal fibular ligament, which also starts at the fibula and ends at the calcaneus or heel bone.

The ligaments are very small and the way that your foot and ankle move put them under a great deal of stress, so they sprain easily.

Basics of sprains

A sprain is a tear of the ligaments. Sprains are graded by severity. A grade one sprain is like a fraying of a rope, a grade two sprain is a partial tear and a grade three sprain is a complete tear.

Ankle sprains are the most common cause of a missed work time injury in the United States, and there are about 2 million ankle sprains in adults each year in the U.S. Not everyone who sprains their ankle develops instability, but somewhere between 20 and 40 percent of people who have an ankle sprain will develop chronic ankle instability.

Injuries associated with chronic instability

One of the common injuries associated with chronic instability is a peroneal tendon tear. The peroneal tendons are a secondary or dynamic stabilizer on the ankle. When the ligaments, the static stabilizers, are not working correctly, then the peroneal tendons will work harder to keep your ankles stable. When they’re working harder, they’re more susceptible to injury.

Another injury is damage to the cartilage in the joint. If that damage builds over time, you can develop ankle arthritis. Unlike hip or knee arthritis, ankle arthritis does not occur from age. Ankle arthritis occurs after chronic ankle instability or a severe ankle injury.

Symptoms of chronic ankle instability

Patients who have chronic ankle instability have always had an ankle sprain, but the ankle sprain may be one year in the past or decades ago. Patients will say they never got all the way better. They never felt like their ankle was ever stable again, or that they were able to trust their ankle. It’s easy to turn or twist their ankle, and they have swelling at the end of the day even if they didn’t do any strenuous activity.

Treatment for chronic ankle instability

Non-surgical treatment for chronic ankle instability

Conservative, or non-surgical, treatments are always the first options. Physical therapy with proprioceptive training, gait training, ankle stabilization and so on is helpful. Bracing can be very helpful and may range from bracing full time to only during high-impact activities, depending on the degree of instability. Anti-inflammatory medications like ibuprofen and Aleve can be very helpful at reducing pain and inflammation if patients are able to take those medications.

We try to avoid long-term activity modification, which sounds like a good idea but means not doing things that hurt. In the short term after an initial ankle sprain, while you’re doing physical therapy, bracing and medication, activity modification is useful to help prevent having a second injury and to allow you to heal. However, the goal of treatment is to be able to get you back to whatever activity you choose, and that means not avoiding activities in the future once you’re successfully treated and have healed.

Surgical treatment for chronic ankle instability

If the conservative treatment doesn’t work, surgical intervention may be warranted. The gold-standard repair is a Brostrom-Gould repair, named after the two physicians who described the surgery. The ligaments on the side of your ankle are retentioned and repaired with a suture into the fibula. The Gould modification includes a thick vein being advanced into the fibula to give a second layer of strength to the repair. This surgery is an excellent surgery for returning people to their desired level of activity.

A newer modification is the Brostom repair with suture tape augmentation. The initial repair is done the same way, but instead of the vein being moved suture tape is anchored into the talus and the fibula to create an internal “seat belt” to prevent the ankle from moving more than it is supposed to. The advantage of this newer version is that patients are able to recover and go through rehab more quickly.

Frequently asked questions

If someone had an ankle sprain decades ago but it is causing pain or weakness now, can they still be treated?

Yes, that is a common issue. You may have some degree of instability that you’re able to tolerate for a long time but it advances and now you’re in pain for everyday activities. Especially if you haven’t been seen for the injury since it originally happened, I recommend seeing a specialist.

What’s the importance of the laces on the ankle brace?

There are many different types of ankle braces. Patients usually choose the ones that are easiest to put on, which are often ones that slide on like a sleeve. However, in my opinion those braces do not give significant support. They can help patients feel better but they do not give stable support to the ankle. While some other types of braces may provide enough support, all of the ones I have seen that have laces on the front will give you the support you need.

Is surgery an option if the ankle sprain occurred decades ago?

Absolutely. It’s not uncommon. The biggest point is to see before the surgery if there are any other associated injuries that have occurred to make sure everything is addressed during the surgery.

What exercises can I do at home to strengthen ankles?

You’ll want to focus on strengthening the peroneal muscles and on balance. It’s best to see a physical therapist at least once if you’re going to start a home exercise program. You can look online and find resources on ankle stability, but online instruction doesn’t replace having someone show you the correct way to do things and walk you through how it’s supposed to be feeling while you do the exercises.

Does chronic ankle instability lead to plantar fasciitis or to Achilles tendon issues?

No, chronic ankle instability is different from plantar fasciitis or Achilles tendon issues. The instability does not directly cause either of the other two issues. However, if you have instability and you change the way that you walk or the things that you do because of it, you may develop other problems.

Is chronic ankle instability more common in specific ages or genders?

No, there’s no typical age or gender. As year-round sports are becoming more common, I see more younger patients. The youngest patient I’ve had to treat for chronic ankle instability was 11 or 12 but I’ve treated people up into their 60s surgically for ankle instability.

What steps should someone with an ankle sprain take to ensure they don’t get chronic ankle instability?

Rest the ankle and don’t put it into a situation where it’s going to be sprained again. Use anti-inflammatory medication like ibuprofen or Aleve, if the patient can take those medications. Elevate the ankle. Ice the ankle and give it some support. Depending on how swollen and tender the ankle is, the support may range from a cast or splint to a boot to an ankle brace to supportive shoes.

The vast majority of people will heal a single ankle sprain on their own without any surgical intervention. The people who are more prone to developing chronic ankle instability try to push healing too quickly after a sprain and then sustain a second ankle sprain while the ligament is still healing.