Broken ankle

What is a broken ankle, and how common is it?

A broken ankle, also called an ankle fracture or malleolar fracture, is a break in an ankle bone. It happens when more force is applied than the bone can take¹. It usually involves the fibula, and the tibia (the larger lower-leg bone) can be affected too¹. The break may be a small crack, a break where the bone shifts out of place, or one where it shatters into pieces².

Ankle fractures are common. They make up to 10% of all bone injuries³, and they're the third most common injury of the bones, joints and muscles in older people⁴.

What causes a broken ankle, and who gets one?

Most follow a twist, a fall or a direct knock to the ankle². A fall from standing height is the most common cause of complex breaks, and some are low-force injuries³. Older women seem to have the highest rate⁵.

In older adults, age, sex, body weight, diabetes, smoking and osteoporosis (thinner, weaker bones) have all been linked with breaks from minor falls⁶. These are links, not proven causes. The link with bone density is small and not consistent⁶.

What does a broken ankle feel like, and how is it diagnosed?

Common signs are swelling, bruising, tenderness, and pain or difficulty walking or putting weight on the ankle¹. Sudden sharp pain, a popping or snapping sound at the time of injury, or an ankle at an odd angle can also point to a break⁷. A sprain can feel similar, and a normal-looking ankle can still be broken. If you can't put weight on it after an injury, see your GP or a podiatrist the same day.

A clinician will examine the ankle and then usually arrange an X-ray⁸. In adults, a checklist called the Ottawa Ankle Rule is good at ruling a break out: a negative result makes a fracture unlikely. A positive result is often a false alarm, so your clinician will combine it with their own judgement⁹.

What helps first?

A suspected broken ankle needs professional care from the start, so don't try to treat it yourself. Treatment depends mainly on whether the ankle is stable¹⁰. Most breaks heal without surgery in a cast or boot, usually for about 6 weeks¹¹. You may be asked not to put weight on the ankle for a while¹².

Surgery, often with metal plates and screws, is more likely if the break is unstable, out of place or open, or if more than one bone is broken². Diabetes, circulation problems and how active you are also shape the plan². Follow your fracture clinic's weight-bearing instructions exactly.

What helps if that isn't enough?

After surgery, putting weight on the ankle earlier (your surgical team will say when) can give slightly better early function and a quicker return to work, without more complications, mainly in lower-risk people¹³. The difference in ankle function is too small to be clinically meaningful¹⁴.

In older adults, treatment is fitted to other health conditions, how well you managed before the injury and your wishes⁴. If recovery stalls, go back to your fracture clinic or GP rather than waiting.

How long does recovery take, and can I stop it happening again?

A cast is usually worn for about 6 weeks, though this varies with the person and the type of fracture¹¹. After a simple break with the ligaments intact, pain may last 6–8 weeks, and it should heal without surgery¹⁵.

Smoking affects healing rates and in extreme cases can stop healing altogether¹⁵. Stopping smoking, controlling alcohol and managing diabetes all play a significant role in healing¹.

It isn't clear yet what prevents a repeat ankle fracture. In older adults, ankle fractures have been linked with lower bone density, so it's worth asking your GP about bone health⁶.