Anatomy of the ankle joint
The ankle joint is a hinge variety of joint, designed in such a way that it provides stability while sacrificing movements. Its main function is to support bodyweight and aid in locomotion. Ligaments are strands of tissue that allow movements within a certain range and in addition provide stability to the joint. The ankle joint is supported (on the outside) by the lateral ligament complex which includes the anterior talofibular ligament (ATFL), the calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL). The medial side of the ankle (inner) is supported by the deltoid ligament. The front of the joint is supported by the anterior inferior tibiofibular ligament (AITFL) while the posterior fibular ligaments attach at the back.
Undue stretching of a ligament leading to its damage is called a sprain. This leads to loss of stability at the joint with abnormal mobility. Depending on the severity of damage undergone, ankle sprains have been traditionally classified into various grades or degrees.
Grade I (First degree)
- most common
- microscopic damage to the ligaments
- no instability at joint
- heals in a short span of time
Grade II (Second degree)
- more severe
- ligaments partially torn
- no significant instability
Grade II (Third degree)
- most severe
- ligaments completely ruptured
- significant instability
The lateral ligaments of the joint are more commonly involved in sprains.
Mechanism of injury
Sprains occur when the ankle is turned unexpectedly which place undue stretch on the ligaments. In sports, sprains occurs with running, jumping, sharp direction changes, or stepping or running on uneven ground. In the normal population, wearing of high heeled or worn out shoes are also a likely mechanism of injury.
Clinical presentation includes
- ligament stress tests (carried out under general anaesthesia, these should be reserved only for research purposes since choice of treatment is not governed by the degree of instability)
X-rays or MRI to rule out damage to other structures, esp. bones.
The first 24-48 hours after the injury is considered a critical treatment period and activities need to be curtailed. Gradually put as much weight on the involved ankle as tolerated and discontinue crutch use when you can walk with a normal gait (with minimal to no pain or limp).
- For the first 48 hours post-injury, ice pack and elevate the ankle sprain 20 minutes at a time every 3-4 hours. The ice pack can be a bag of frozen vegetables (peas or corn), allowing you to be able to re-use the bag. Another popular treatment method is to fill paper cups with water then freeze the cup. Use the frozen cube like an ice cream cone, peeling away paper as the ice melts. Do NOT ice a ankle sprain for more than 20 minutes at a time!! You will not be helping heal the ankle sprain any faster, and you can cause damage to the tissues!
Use compression when elevating the ankle sprain in early treatment. Using an Ace bandage, wrap the ankle from the toes all the way up to the top of the calf muscle, overlapping the elastic wrap by one-half of the width of the wrap. The wrap should be snug, but not cutting off circulation to the foot and ankle. So, if your foot becomes cold, blue, or falls asleep, re-wrap!
Keep your ankle sprain higher than your heart as often as possible. Elevate at night by placing books under the foot of your mattresses–just stand up slowly in the morning.
More severe ankle sprain injuries, including complete tears of the ligaments and fractures of the bone may need different treatment and rehab than a simple ankle sprain. It is important that you see your doctor before beginning treatment or if your symptoms do not steadily improve over time.
The aim of the treatment is to reduce oedema (fluid accumulation, responsible for the swelling) and increase circulation, thereby facilitation removal of debris. The methods by which this can be achieved are cryotherapy (cold therapy) and exercise respectively. Some researchers advocate exercising during the rehabilitation phase when the swelling has subsided.
Controversy also exists regarding the use of heat. Most authorities claim that heat should not be applied till oedema recedes. However, some studies are in favour of early use of heat suggesting that heat does not significantly affect oedema.
Most scientific studies are in support of early mobilization for the treatment of ankle joint sprains. This combined with physiotherapy is the best treatment available to get the sports person back to match fitness. Although, some studies suggest that the long term effects of surgical repair as compared to early mobilization or cast immobilization are minimal, there are conflicting reports. Scientific data suggests that surgical repair should be the choice of treatment only in patients with persistent instability.