What to Know About a Lateral Malleolus Fracture

Medically Reviewed by Dany Paul Baby, MD on April 27, 2022
4 min read

The lateral malleolus is the bone on the outside of the fibula. A lateral malleolus fracture is a type of ankle fracture that occurs when the fibula fractures just above the ankle joint. It is the most common type of ankle fracture and may happen when the foot rolls or twists.

The knobby bones on the outside and the inside of the ankle are called malleoli. The fibula and the tibia have specific parts that compose the ankle:

  • Lateral malleolus - end of the fibula
  • Medial malleolus - inside part of the tibia
  • Posterior malleolus - the back part of the tibia

A fracture on the outside of the ankle, the lowest part of the fibula, is the most common site of such an injury. The bumpy knob that is broken in such cases is called the lateral malleolus.

The lateral malleolus is at the end of the fibula, a smaller bone in the leg. When part of this bone fractures, the ankle can become unstable. A fracture can be caused by a fall, a blow to the ankle, or twisting of the foot or ankle.

An ankle that is fractured can consist of a simple break of one bone or several fractures. Many fractures can force your ankle out of alignment and force you not to place weight on it for months. The more bones are broken, the less stable the ankle becomes. Some soft tissue, called ligaments, may be damaged as well. The job of the ligaments is to hold the ankle joint and bones in the correct position. 

A fracture of the fibula just above the ankle joint is called a lateral malleolus fracture. There are three different levels at which the fibula. The level determines future treatment. Causes of lateral malleolar fractures include:

  • Tripping and falling
  • Rolling the ankle
  • Car accident trauma
  • Twisting and rotating the ankle

Breaks that happen suddenly, or during a specific injury or incident are called traumatic ankle fractures. A bone can also break because of continuous stress to one area over time. This is called a stress fracture. Lateral malleolus fractures can cause several different types of symptoms. It can also be tender to the touch and make walking or weight-bearing difficult and painful.  

Common symptoms for those suffering from a fracture include:

  • Bruising
  • Instant and severe pain
  • Painful to touch
  • Non-weight bearing on the injured foot
  • Swelling
  • Deformity of the ankle, especially if dislocated

Because a broken ankle could also have the same symptoms as a severe ankle sprain, though, all ankle injuries should be checked by a doctor. 

Doctors initially use X-rays to find out if there is a broken bone instead of an injury of the soft tissue like an ankle sprain. Ankle sprains and fractures often have the same symptoms. Other types of imaging used to determine the injury level include MRI or CT scans. These give more information of what the full scope of the injury is.

If imaging comes back and you have an ankle fracture, an orthopedic should be contacted as soon as possible. There are very many types of ankle fractures, but not all of them need surgery. If they do, the appropriate specialist must begin treatment soon. 

The ankle joint is very important when it comes to walking and stability.

An improperly done surgery can lead to a line of extensive treatment, including corrective surgeries. This can also lead to arthritis, ankle instability, and perhaps even an ankle joint replacement. 

Proper intervention is vital in preserving the function of the ankle for the future.

A lateral malleolus fracture can happen at several different levels. Treatment depends on the fracture location. If the broken bone is stable and not dislocated, treatment may just consist of palliative care and immobilization. A lateral malleolus fracture can be managed with self-care by elevation, rest, ice, and anti-inflammatory medications.

Non-surgical treatment when the ankle is stable can consist of several supportive elements. While it heals, support may be rendered by wearing a high-top tennis shoe, or a short leg cast. Some doctors allow patients to immediately walk on the affected leg. Some may recommend holding out for six weeks.

If the ankle is unstable or the bones are out of place, the fracture may need to be treated with surgery. During the procedure, the bone fragments are repositioned into normal alignment. They are held in place with special rods, screws, or metal plates attached to the outside of the bone. 

Sometimes, the screw or rod in the bone might be used to just hold the bone fragments in place while they heal.

A fracture of the lateral malleolus usually means a person will have to avoid placing weight on their ankle for at least a few weeks. Normally, you can return to daily activity in 3 to 4 months. 

Strengthening and stretching exercises that are prescribed by a medical professional can help to improve mobility and function during the healing process. It takes approximately 6 weeks for bones to heal, and associated ligaments and other soft tissue even longer.

A pain management protocol is given to the patient, typically in hopes that opioid medications will not be needed. For the first few weeks, you will be in a splint and required to elevate your leg for most of the day. 

After about 2 weeks, stitches are removed, and you are placed in a removable boot. The patient is allowed to move their ankle and shower. At about 6 weeks, you follow up with your doctor, and new X-rays are taken.