A to Z: Fracture, Lateral Malleolus

May also be called: Lateral Malleolar Fracture

A lateral malleolus (muh-LEE-uh-lus) fracture is a type of broken ankle that happens when part of the fibula just above the ankle joint fractures.

More to Know

The bony knobs on the inside and outside of the ankle are called the malleoli, which is the plural form of malleolus. The knob on the outside of the ankle, the lateral malleolus, is the end of the fibula, the smaller bone in the lower leg. When this part of the bone fractures, or breaks, it's called a lateral malleolar fracture. This type of fracture can be caused by twisting of the foot and ankle, a trip or fall, or a direct blow to the ankle.

Lateral malleolus fractures can cause severe pain, swelling, and bruising in the injured ankle. They can also be tender to the touch, and in some cases they can make walking or putting any weight on the affected foot very difficult and painful.

The lateral malleolus can fracture at a number of different levels, and treatment often depends on where the fracture is located. If the broken bone is not out of place and the ankle is stable, treatment may consist of just wearing a special boot or cast to immobilize the ankle as it heals.

In some cases, though, surgery has to be performed to align the bone and hold it together with metal plates, rods, or screws. In general, it takes at least 6 weeks for the broken malleolus to heal.

Keep in Mind

A lateral malleolus fracture usually requires the person to keep weight off the affected foot for a few weeks. In most cases, people return to normal daily activities within 3 to 4 months. Stretching and strengthening exercises supervised by a doctor or physical therapist can help improve ankle function and mobility during the healing process.

All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.