Do You Have Chronic Ankle Instability and Not Even Know It?

Hunter Sparks, SPT – Texas State University Doctorate of Physical Therapy Class of 2024

In order to know whether or not you have chronic ankle instability, you must first know what that term means. Chronic ankle instability (CAI) is when an individual has ongoing persistent symptoms of instability, pain, and weakness following an ankle sprain injury. These symptoms can last months or even years. People who suffer from CAI tend to frequently re-sprain their ankles – sometimes without really having a significant injury event. Additionally, these persons typically report poor balance and decreased ankle mobility – particularly in dorsiflexion range of motion, which is the ‘toes towards the nose’ movement that enables squatting. Do these symptoms describe you? If so, there is a high likelihood you have CAI. This is a fairly common problem in active populations, so don’t worry – you are not alone!  And good news – there are treatments that can help!

Want to know for sure if Chronic Ankle Instability is a diagnosis that describes you? There are a few clinical tests you can complete to know for certain. One is the Cumberland Ankle Instability Tool. This is a 9 item, 30-point scale questionnaire. Scores of 25 or less are indicative of chronic ankle instability. The questionnaire is quick and easy, and luckily for you, it can be found online here! Another assessment tool is the Time-In-Balance Test. This test can also be conducted in the comfort of your own home. All you have to do is measure the length of time that you are able to balance on a solid surface on one leg with your eyes closed while your hands rest on your hips. Make sure you have a stable surface nearby to grab onto should you lose your balance. No need to injure the other ankle as well! Average scores of 26 seconds or less (using scores from 3 attempts) suggest chronic ankle instability when using this test.

The next two tests are not as easy to complete on your own and require either a skilled physical therapist or unique equipment to complete. They are the Reverse Anterolateral Drawer Test and the Modified Star Excursion Balance Test. The Reverse Anterolateral Drawer Test is performed by having a PT stabilize a person’s heel while also pushing against the lower part of the large shin bone while measuring how far the bones move in comparison to one another. CAI is suspected if there is excessive movement of the bones when compared to the person’s uninjured ankle. Another clinical assessment is the Modified Star Excursion Balance Test. For this test, a person will stand barefoot on one leg at the center of a grid. Then one would put the hands on your hips and reach with the opposite foot as far as possible in several directions. Four practice trials are allowed in each direction, so don’t worry if it takes some time to get the hang of it. During the test, people are also given 5 minutes of rest after each direction is tested and 10 seconds of rest between trials to prevent fatigue. After all of the testing, which occurs on both feet, the distance scores are calculated into a total ‘composite’ score.   CAI is suspected if the person tested is only able to reach 91%  or less of the distances with the injured ankle in comparison to the unaffected side.

So what if it’s discovered that you DO in fact have chronic ankle instability? What’s next? Do you give up and accept your fate of repeated injury and activity disruption? No need for that, because there are a variety of ways to treat this condition! Working with a physical therapist is a great way to improve your functional stability & confidence during activity!  A therapist will often start with prescribing a variety of proprioceptive and neuromuscular therapeutic exercises. These specific exercises improve your ability to know where your body is in space and strengthen your mind-muscle communication connections. Patients who utilize these exercises are found during research studies to see improvements in things like muscle reaction time, postural sway (how much ‘wobble’ there is during a balance task) and isometric muscle strength (the force generated by a muscle when it is kept at a constant length). Some specific exercises that might be used for these purposes are single leg balancing on an unsteady surface, controlled movement while standing on a balance board, or even prescribed-interval walking on an uneven surface such as an uphill driveway or a gravel path. A physical therapist can help you to gradually progress activities over time in a safe manner until you are able to maintain good functional stability even when accomplishing challenging tasks, such as dancing or participating in other multi-directional activities in various sport and recreational pursuits.

Another treatment approach for chronic ankle instability is to improve your ankle mobility. This sounds counterintuitive when an ankle is unstable.  However, remember that many people with this condition end up with ankle stiffness in a specific pattern – pulling the toes towards the nose.  In cases of CAI, some parts of the ankle move too much, but others become too stiff – either because of 1 injury or after repeated injuries over time.  Redistributing shock absorption capacity so that all joints in the ankle are moving as efficiently as possible will help to reduce the chances of reinjury and can make load-bearing activity more comfortable.  Improving ankle mobility can be accomplished through the completion of passive ankle joint mobilizations performed by a physical therapist or active mobilizations with movement, where a patient and therapist work together to accomplish movement. One way that you can try to mobilize the ankle joint by yourself is to step onto an elevated surface such as a low foot stool with the injured ankle and then bend the knee forward and shift some body weight over the foot while keeping the foot locked in place. In doing this you should feel a stretch in the back of the heel if you are performing the motion correctly.

Lastly, to treat a CAI condition, you may also want to invest in a semi-rigid ankle brace. It is suggested that you only utilize the brace when you are participating in activities that put the ankle at risk – such as competing in athletic events or hiking on uneven ground. This brace can act as a protective device in these cases. Braces are not to be worn at all times, as their use can actually diminish the body’s ability to learn to stabilize the ankle joint on its own.

Now that you understand what CAI is and how to begin treating it, it’s time you got to work! Seeking out a physical therapist’s assessment in conjunction with considering the previously listed activities is a great place to start! Thank you for taking the time to read this post and good luck with your recovery!


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