What is chronic ankle instability?
Ankle instability typically refers to a weakness within the ankle joint and is characterised by the recurrence of the ankle joint ‘giving way’, or undergoing a lateral ankle sprain.
Firstly, let’s take a look at what the ankle joint is responsible for.
It is a synovial hinge joint that connects the lower leg to the foot and is composed of 3 bones – the fibular, the tibia and the talus, as well as multiple ligaments and tendons.
The ankle joint typically moves in plantar flexion and dorsiflexion, allowing you to take each step and for your feet to clear the ground so that you do not trip or fall over.
A lateral ankle sprain involves an outwards motion of the ankle, causing injury to the lateral aspect of the ankle.
Ankle sprains can account for up to 30% of sporting injuries and approximately 20% of those injuries can result in chronic ankle instability.
During an ankle sprain, the ligaments and tendons can become stretched and even torn. This is what ultimately leads to ankle instability, as it damages the integrity of the joint.
Ankle instability is generally diagnosed following repeated ankle sprains where the ankle joint does not recover properly and cannot maintain its strength.
Along with recurrent ankle sprains, perceived instability and ligament laxity can contribute to chronic ankle instability.
These can occur both independently from each other, or in combination. Those who have chronic ankle instability can present with reduced balance and strength, as well as altered range of motion through the ankle joint.
Ankle instability can be characterised into 3 categories:
- Mechanical instability – this refers to ligament laxity and pain. It can be diagnosed through a physical examination and scans (X-ray, ultrasound, MRI).
- Functional instability – this refers to an inability of the ankle joint to function properly or effectively and may be diagnosed through clinical tests such as balance and strength exercises.
- Perceived instability – this refers to the ‘feeling’ of instability or a fear of reinjury.
What are the risk factors and causes of chronic ankle instability?
The risk factors for ankle instability can include:
Repeated ankle injuries
As previously mentioned, previous injury to the ankle is what ultimately leads to ankle instability. The soft tissue may be stretched or torn and the bones may be fractured or bruised. If these tissues have been damaged and are not rehabilitated properly, it can lead to prolonged weakness and a high risk of re-injury.
Those with high arches, known as a cavus foot type, are at a high risk of repeated lateral ankle sprains because there is increased pressure on the outside of the ankle.
Those with low arches, known as a planus foot type, are also at risk. In this foot type, the soft tissue and joints within the feet tend to be hypermobile and flexible, which ultimately contributes to reduced balance and strength.
Whilst ankle sprains can occur in everyday life, repeated ankle sprains are higher in the sporting population. This is because there is increased pressure placed on the ankle in most sports including football, netball, hockey, basketball, lacrosse etc.
Balance can be affected by a number of factors including vertigo, inner ear disorders and blurred vision. If medical episodes happen frequently, you are more at risk of losing your balance and injuring yourself, particularly at the ankle joint.
Training on proper surfaces is very important for a number of reasons, but it mostly reduces your risk of injury in general. Any environment where the ankle has to work harder to keep you balanced and functioning, the higher the risk of injury is.
Improper footwear can contribute to repeated ankle sprains. For example, those who wear high heels frequently are at a higher risk of recurrent ankle sprains as the ankle is placed in a compromising position.
A higher body mass index (BMI) can increase the risk of repeated ankle sprains due to the amount of force being applied to the ankle and feet in general.
What does ankle instability feel like?
Ankle instability can present in a number of ways:
- Persistent discomfort and swelling
- Pain and tenderness through the ankle joint
- Feeling unstable or weak through the ankle joint, or feeling as though it will ‘give way’
Can chronic ankle instability lead to other issues?
Put simply, if repeated ankle sprains are not treated properly, it may cause other issues within the feet and ankles.
Chronic regional pain syndrome
This refers to ongoing pain and inflammation in a certain area. If the ankle is repeatedly injured, the pain and inflammation may not be able to settle.
The peroneals are a group of muscles that sit on the outside (lateral aspect) of the leg. Their tendons run through the lateral ankle and are often injured in an ankle sprain. Inflammation of these tendons can contribute to your pain and ankle instability.
Dislocation or subluxation of the ankle joint, fractures of the bones
The bones within the ankle joint can also be damaged in repeated ankle sprains.
Sinus tarsi syndrome
The sinus tarsi is a structure within the foot that can also be damaged and contribute to lateral ankle pain and instability.
How can we test for ankle instability?
Range of motion
We test movement within the ankle, as well as the other joints within the feet. A restriction in motion or hypermobility can indicate ankle instability.
The muscles of the lateral ankle (peroneals) may weaken over time due to repeated ankle sprains. We test the strength of these muscles when you’re sitting and standing.
We can test your balance using the Romberg’s manoeuvre
You will stand barefoot with your feet together and your arms either crossed over your chest or outstretched by your sides. We begin with your eyes open and then progress to eyes closed. You are then scored by the number of seconds that you are able to stand without losing balance. We will repeat this but on a single leg.
Double/single leg calf raises
This will test the range of motion through the ankle, as well as the strength of the calves muscles that help to move the ankle joints.
This test will assess you balance and strength and involves you standing on one leg and reaching the opposite foot out to different points on the ground.
Plyometrics /sport specific exercises
These will involve stressing the ankle joint in movements where it may be vulnerable. This includes jumping, hopping and change of direction exercises.
What are the treatment options for chronic ankle instability?
Depending on the severity of injury, chronic ankle instability can be managed in a number of ways.
It is important to know that the threshold for healing is different for everyone and treatment will depend on this along with the severity.
Chronic ankle instability may never fully heal, however we will work with you to identify your concerns and areas that need to be treated in order to get you moving pain free.
Strengthening the ankle joint itself, as well as the muscles in the lower leg and feet will help to reduce pain and improve balance and motion. Strengthening programs are tailored to your need based on the severity of your injury, your goals for rehabilitation, your activity and your current level of fitness and strength. Exercises can include using a theraband or a wobble board, calf raises, plyometric exercises such as jumping or hopping and sport specific exercises that focus on change of direction and balance training.
Taping and bracing
Protecting your ankle with taping or bracing will not only help reduce your risk of injury, it also has a psychological benefit. It can help to reduce the feeling of the ankle giving way, or a fear to recommence activity. There are various types of taping and bracing available and your podiatrist will discuss with you which one is right for you.
Orthotics can help to manage ankle instability by addressing foot posture and function. They can realign the foot and ankle into a more optimal position, as well as provide support to the structures that need it most, including the ankle joint. Orthotics work particularly well for those who suffer from recurrent ankle sprains.
This can help to reduce tension and pain in the muscles that can be injured in acute or repeated ankle sprains, typically the peroneal muscles.
Shockwave therapy can help to reboot the healing process of injured structures, reduce pain and increase blood flow. It won’t necessarily help with increasing strength within the ankle joint, but can assist with pain reduction to allow you to move more comfortably.
Wearing appropriate footwear is important to support the body properly from the feet up. We know that certain types of shoes can contribute to your risk of ankle instability, therefore bringing in the shoes you wear most often to your podiatry appointment will allow us to assess them and provide recommendations on what shoes are best for your feet.
The need for surgery is based on the degree of instability and the severity of the injury. It is not required for everyone and generally requires undergoing a conservative management plan first. Surgery typically involves repair and reconstruction of the damaged ligaments and tendons within the ankle joint.
Do I need to stop playing sport?
Definitely not! It is normal to feel scared about returning to activity after an ankle sprain, particularly if they are recurrent.
The goal of treatment is to allow you to participate in whichever physical activity or sport that you would like, whilst also keeping you safe from further or future injuries.
It may take time for you to be able to return to sport after an ankle injury, however the aim is to ultimately prevent chronic ankle instability.
There is no overnight cure unfortunately and treating ankle instability can take time and patience.
How to prevent ankle instability?
So how can you prevent chronic ankle instability?
Seek treatment for an ankle sprain as soon as possible
Early intervention is always best and can help to reduce long term complications or recurring injuries.
Stick to your rehab program!
This is sooooo important, we can’t stress this enough. The rehabilitation plan we give you is a targeted approach and needs to be followed closely to optimise your results.
See a podiatrist if you are worried about your risk of ankle sprains
We can provide a comprehensive assessment to identify any risk factors and come up with a treatment plan that is right for you.
So if you’ve injured your ankle recently or you are experiencing any pain or discomfort in your feet and/or lower limbs, book in to see us here at Watsonia Podiatry. You can make an appointment online here or call us on 03 9432 2689.