Jul 27, 2020
The Most Common Types of Ankle Fractures
Simon Moyes, a consultant orthopaedic surgeon, discusses the most common types of ankle fractures from fibula fractures to maisonneuve fractures.
Millions of people break their ankles every year, but not all ankle fractures are the same. They range from small, hairline fractures to complex breaks involving a number of bones.
If you have injured your ankle – particularly if it feels like a simple sprain – it is tempting to try to carry on walking on it, once the pain subsides. In many cases, people who have broken their ankle don’t get an x-ray for some days or weeks. Depending on the type of fracture, this can lead to complications in the healing process.
For this reason, it’s good to know the different types of broken ankle and what impact they can have on your recovery and long-term ankle stability.
Your ankle joint is made up of three bones – the talus, the tibia (the large shin bone) and the fibula (the slim calf bone that connects to the outside of your ankle joint).
Stable vs Unstable ankle fractures
Stable fracture: although a bone is broken, the ankle joint itself remains well positioned and stable – theses are normally managed with a walking cast or boot.
Unstable ankle fracture: the stability or structure of the ankle joint is affected by the break. This kind of fracture can involve the ligaments that hold the joint together, the joint surfaces themselves, or a combination of both. These normally require surgery.
Different types of ankle fractures
Fibula Only Fracture (lateral malleolus fracture)
The base of the fibula (the lateral malleolus) forms the bony lump on the outside of your ankle. It can get broken if you twist your ankle forcefully, land on it badly, or through an impact on your outer leg. It is the most common type of ankle fracture.
These fractures are very common in sports, especially those that involve running, jumping, quick changes of direction or high-impact contact – such as football, basketball or rugby.
The fibula (calf bone) attaches to the outside of the ankle with three strong, fibrous ligaments. When you roll over on your ankle or twist it sharply, the ligaments get stretched and pull on the bone. The stress can cause a fracture in the fibula or even tear a chunk of the bone away (avulsion fracture).
Fibula fractures can also occur as a result of repetitive stress from activities such as running or hiking.
If you have suffered a high impact such as a car accident or a serious fall, the broken fibula might get displaced – sometimes breaking the skin. These unstable fractures usually require surgery to repair the joint.
Bimalleolar Ankle Fracture
The second most common type of ankle fracture is a break of both the fibula on the outside of the ankle, and the base of the tibia (shin bone), on the inside of your ankle. Most bimalleolar ankle fractures are serious injuries. They’re usually the result of high impact injuries such as falls and road traffic collisions. In addition to the force of impact, there is often a significant force of rotation on the ankle, which can lead to serious ligament damage.
These are the most severe of ankle fractures and have a poor prognosis. With these fractures, the back of the tibia / shinbone is also broken off. As with bimalleolar ankle fractures, they are the result of an extremely high-energy impact.
Tibia Only Fracture (pilon fracture)
The tibia (shin bone) can break in one place or shatter in a number of places at the ankle joint. Like bimalleolar and trimalleolar fractures, these fractures are caused by a high energy impact, for example a car accident, a fall from height or a skiing accident.
Bimalleolar, trimalleolar and tibia-only fractures should be reviewed immediately with an x-ray, and usually require a cast to stabilise the joint as the bone heals. Sometimes these fractures can occur in lower-force impacts due to osteoporosis, which causes the weakening of your bones.
For any unstable fracture (ie the bone has been displaced), surgery will usually be necessary to reposition the bone.
A Maisonneuve fracture can be mis-diagnosed as an ankle sprain (stretched ligaments), because an x-ray of the ankle shows no break in the bone.
However, the stress from the ankle injury (usually a result of rolling over or twisting your ankle) can cause the fibula (calf bone) to fracture higher up towards your knee.
The pain is usually felt around your ankle, and the injured ligaments will make your ankle feel unstable – hence the mis-diagnosis of a sprain.
If a Maisonneuve fracture isn’t picked up immediately after the injury, you may need surgery to fix the break in your fibula and repair the ligaments in your ankle.
Treatment for Fractures at Simon Moyes
If your broken bones lead to instability and ongoing mobility issues, you are likely to require surgery – so getting the correct diagnosis is vital.
Using physical tests, x-rays and MRI scans, Simon Moyes and the Capital Orthopaedics team can assess the type of ankle fracture, review any soft tissue damage – such as torn ligaments – and diagnose any bone conditions such as osteoarthritis or osteoporosis.
Surgical treatment may involve repositioning bones using surgical pins, removing bone fragments and repairing damaged ligaments. Often, this can be done using keyhole or arthroscopic surgery – a more precise method of surgery with shorter recovery times.
Simon Moyes is a world-renowned orthopaedic surgeon in London, supported by a team of expert radiographers, nurses, physiotherapists and sports medicine professionals at The Cromwell Hospital, The Basinghall Clinic and the Platinum Health Centre.
For any concerns about ankle injuries, or for referrals from your doctor, contact Simon here.