Sprained ankle

If the foot rolls, whether while walking, jumping or running, the result may be a sprained ankle. That is because the ligaments are overstretched during twisting. What is more, small blood vessels rupture, causing the ankle to swell up and become painful. 

At a glance

  • During twisting, the ligaments are overstretched, and they can even rupture in a worst-case scenario. 
  • What is more, small blood vessels rupture, causing the ankle to swell up and be painful. 
  • If it is still possible to put weight on the foot and walk immediately after twisting, it is likely that nothing is broken. 
  • If the ligaments are only slightly stretched, the foot can usually be moved normally again after a few days. 
  • Sprained ankles without a ligament rupture are usually largely better after 2 weeks. 

Note: The information in this article cannot and should not replace a medical consultation and must not be used for self-diagnosis or treatment.

Sprained ankle: jogger standing with both legs on an asphalt racetrack. The sportsman is lifting his right leg up slightly by the heel so that he is standing with one leg on the football.

What is a sprained ankle?

If a person's foot rolls too heavily, ankle joint ligaments can be overstretched. The surrounding tissue is also injured in the process. The joint swells up and is painful. It is sprained. Ankle sprains are among the most common injuries. 
 
Ligaments are durable yet flexible bands of connective tissue that bind bones together in a joint. The ankle joint is made up of many bones. So there are also several ligaments here that stabilize it. 

What are the symptoms of a sprained ankle?

When twisting is too severe, the ligaments are overstretched. In a worst-case scenario, they may even rupture. Moreover, overstretching causes small blood vessels to rupture. The ankle then swells up and is painful. 
 
If it is still possible to put weight on the foot and walk immediately after twisting, it is likely that nothing is broken. If the ligaments are only slightly stretched, the foot can usually be moved normally again after a few days. But even slight sprains can hurt. 

What are the causes of a sprained ankle?

The ankle joint enables the foot to move up, down and sideways. Inward rotations are easier than outward ones. The foot therefore mostly rolls inward – for instance with a bad landing after a jump. The ligaments on the outside of the ankle, known as lateral collateral ligaments, can be injured in the process. In rarer instances, the ligaments on the inside of the ankle, known as the medial collateral ligaments, are overstretched when it is twisted. 

Important: Some people have very weak ligaments. They are thus prone to sprains. People with contracted foot or muscle weakness also have a higher risk. 


Sportspeople moreover experience sprains and other ankle injuries more frequently. So for example, a quarter of all sportspeople get lateral collateral ligament ruptures on their ankles. This is especially the case for sports such as volleyball, basketball or football. 

How does a sprained ankle develop?

In most cases, ankle sprains without a ligament rupture are largely better after 2 weeks. While it is not yet possible to put full weight on the foot, it no longer hurts much. 
 
If the ligaments have torn or ruptured, it can take weeks until the ankle joint no longer gives any problems.  In the case of a more serious ligament injury, it sometimes takes 2 to 3 years until the ankle joint is as flexible and able to have as much weight put on it as before. 
After a sprained ankle, the risk of new foot injuries in subsequent years is higher – especially when the joints are under severe stress, such as while playing sports like football or basketball. 

For around 10 – 20% of people with severe ankle sprain their ankle will be permanently unstable afterwards.

For around 1 to 2 out of 10 people with a severe sprain, their ankle joint will be permanently (chronically) unstable afterwards. The joint then still yields too easily even 6 months after the sprain. People with a chronically unstable ankle joint often sprain their ankle repeatedly. 

How can a sprained ankle be prevented?

To stabilize and protect against new injuries, some people put a bandage or splint on their ankle joints before playing sports. 
 
Constantly unstable ankle joints can be prevented in particular by strengthening and coordination exercises. Those who want to restore their joint structure usually have to exercise for weeks or months. A balancing board that tips on its side as soon as there is slight imbalance is often used for that. For example, the board is used to practice standing on one leg. In order not to lose balance, the foot must counteract the tipping, offset various loads and execute movements. The muscles are thus strengthened and the ankle becomes more stable. 

How is a sprained ankle diagnosed?

In the event of a possible sprained ankle, the doctor firstly asks about the circumstances of the accident and symptoms. The severity of the injury is then checked in the examination. If an ankle fracture needs to be ruled out, the foot can moreover be X-rayed. 
 
If the symptoms of an ankle sprain have not clearly improved after a few days, there may be a ligament rupture. In such cases, an image of the inside of the ankle joint can be created using magnetic resonance imaging (MRI). With these kinds of MRI images, the ligaments and surrounding tissue can often be better appraised than with an X-ray image. 

How is a sprained ankle treated?

A sprained ankle swells up quickly and also rapidly starts to hurt. As an immediate action against the pain and swelling, it is best to elevate the foot and cool it. A compression bandage that puts slight pressure on the ankle is also helpful. These palliative measures are usually enough for a mildly sprained ankle. 

A sprained ankle can be treated with rest, cooling and a compression bandage.

If necessary, a splint, orthosis or solid bandage can be applied to stabilize the foot. If the ankle joint is severely swollen, a plaster can also be a sensible short-term option. 
 
It is important not to immobilize the foot for too long and start appropriate movement of it as soon as possible. Surgery is only rarely required for a sprained ankle with ligament rupture. 

You can find more detailed information, for example about how a sprained ankle is treated, at gesundheitsinformation.de.

In cooperation with the Institute for Quality and Efficiency in Health Care (Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen) (IQWiG). As at:

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