What is an ankle sprain?

An ankle sprain is when you twist your ankle in an abnormal way causing tearing or stretching of ligaments that help to hold the bones of your ankle into place.  The function of ligaments is to prevent excessive movement of your ankle bones and help to stabilise your ankle joint.  The most common injured site in an ankle sprain is the outer or lateral side of your ankle.  The signs and symptoms mainly include pain and swelling of your ankle.  This condition can be diagnosed clinically, meaning that using only a good history and physical examination is often enough to make the diagnosis.

In the United States, there is around 23,000 people per day requiring medical care for ankle sprains.  This condition can be self-treated and therefore many people do not even go to the hospital.  In addition, female athletes are 25% more at risk of having an ankle sprain than male athletes.  The most common sports associated with ankle sprains include basketball, soccer and volleyball.

What are the causes of an ankle sprain?

An ankle sprain usually occurs when your ankle is forced into a position which it is not supposed to be.  This leads to stretching or tearing of the ligaments holding your ankle bones in place.  Common causes of ankle sprains include:

• Having a bad landing after jumping
• A slip or fall resulting in twisting of your ankle
• Exercising or walking on an uneven surface
• Someone landing or stepping on your ankle causing your ankle to twist- like in a tackle in soccer.

What are the risk factors for an ankle sprain?

There are several factors which may increase your risk of having an ankle sprain and these include:

• History of ankle sprain: If you had an ankle sprain before, you are at an increased risk of having future ankle sprains.
• Sports: Participating in sports such as volleyball, soccer and basketball increases your risk of having an ankle sprain as these sports require you to jump and perform other demanding actions.
• Irregular or bumpy surfaces: Walking or running on irregular surfaces increase your risk of having an ankle sprain.
• Poor physical condition: Having a poor physical condition or weak foot muscles increases your risk of having an ankle sprain as the stability or strength of your ankle is less.
• Obesity: Being overweight or obese increases your risk of developing an ankle sprain as more pressure or force is exerted over your ankle.
• Shoes: Wearing high heels, shoes that does not fit properly or shoes that are not appropriate for an activity, increases your risk of having an ankle sprain.

What are the signs and symptoms of an ankle sprain?

The signs and symptoms of an ankle sprain include:

• Pain when walking
• Pain when you touch the affected part of the ankle
• Swelling of the ankle
• Limited range of motion of the affected ankle
• Bruising at the site of tenderness
• A pop sound or sensation at the time of injury
• Instability of the affected ankle

If after the injury, you can walk even if there is pain, the possibility of it being a fracture is low.  Sudden, intense pain and rapid swelling indicates a ruptured ligament.  The more swelling and bruising there is, the more likely it is to be a fracture.

Making a diagnosis

To make a diagnosis, your doctor will first take a history from you to know more about your symptoms and how the injury occurred.  After the history taking, your doctor will perform a thorough physical examination to look for signs of an ankle sprain.  There are special test which your doctor will perform during the physical examination such the anterior drawer test, talar tilt test, external rotation test and squeeze test.  These special tests are design to identify which part of your ankle is affected.  Your doctor may order some tests in order to confirm the diagnosis and to rule out a fracture and these include:

• Plain radiograph imaging: During the physical examination, if your doctor locates certain specific tender points in your ankle, he/she will order an ankle x-ray to rule out a fracture. 
• Computed Tomography (CT) scan: A CT scan is done if imaging of the soft tissues of your ankle is required or your doctor suspects another condition causing your signs and symptoms.
• Magnetic Resonance Imaging (MRI) scan: An MRI scan is done in people with a history of recurrent ankle sprains and chronic pain.
• Arthrographic imaging: This imaging technique is only required if surgery is needed.  This imaging technique involves your doctor injecting a dye or contrast material directly into your ankle joint to have a more accurate imaging.

What are the treatments of an ankle sprain?

The treatment of ankle sprain depends on the severity of the condition.  The most important self-care knowledge about ankle sprains is “R.I.C.E.” which stands for rest, ice, compression and elevation.  Rest is important to avoid unnecessary pain and further swelling.  Ice is to be applied on the ankle as soon as possible to help decrease the pain and swelling.  The application of ice should be repeated every 2-3 hours.  To help decrease the swelling even more, compress the ankle using an elastic bandage until the swelling is gone.  Elevation of your ankle about the level of your heart help to decrease the swelling of your ankle.  Furthermore, you can use crutches to help relieve pressure on the affected ankle.

Medications such as acetaminophen or non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or diclofenac can be used to relieve your pain.

Your doctor will teach you some exercises which will help you to restore ankle’s range of motion.  This will also strengthen the muscles of your ankle in order to increase your stability and prevent recurrent ankle sprains.

Surgery is done only in cases where there is still pain or instability after a long period of physical therapy or exercises.  Surgery is performed to repair torn ligaments or tendon.

What are the complications of an ankle sprain?

Complications of an ankle sprain include:

• Chronic ankle pain
• Chronic instability of your ankle joint
• Inflammation of your ankle joint (arthritis)

Prognosis

When ankle sprains are treated properly, the prognosis is excellent.  Full recovery of an ankle sprain is achieved after 2 weeks to 36 months with most recovery occurring within 6 months.  Unfortunately, 3-34% of people who have had an ankle sprain have reported re-sprains after 2 weeks to 96 months.

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