Do you put a cast on a broken fibula?

The fibula is the smaller of the two long bones in the lower leg. It is located on the outer or lateral edge of the leg, and is connected to the other long bone (tibia) at the top and bottom by strong ligaments.

The fibula is a slender, non-weight bearing bone whose main function is to serve as an attachment point for muscles. (see references 1)Treatment of a fibular fracture will depend on a variety of factors, including which part of the fibula is fractured, and how severely.

Types of Fractures

There are two main ways a bone like the fibula can be fractured. One is through an acute trauma such as a fall or car accident, and the other is a stress fracture caused by repetitive movements like running. If the bone comes out through the skin when it is fractured, it is known as a compound fracture and requires immediate emergency care. Fractures can occur anywhere along the bone, but the severity of the injury, and ultimately the prognosis for recovery depend on the location of the fracture. The fibula can be divided into 3 main parts--proximal(closest to the knee), mid-shaft, and distal(closest to foot). A fracture to the proximal or mid-shaft of the fibula is usually less severe than a fracture to the distal fibula. The distal fibula is known as the 'lateral malleolus' and is easily identifiable as the large 'bump' on the outside edge of your ankle. A fracture to this part of the fibula often results in more severe symptoms and a greater loss of function. (see references 1)

Fracture Signs and Symptoms

Acute or compound fractures of the fibula are associated with sudden pain, rapid swelling, loss of function, tenderness, possible deformity, bruising, and sometimes a 'pop' or 'snap' sound. (see references 2)Patients with stress fractures also have tenderness, swelling, and possibly some loss of function, but the pain may go away with rest causing the person to dismiss the injury or not seek treatment. (see references 2)As with all fractures, the only way to know for sure is to have an X-ray taken and examined by your doctor.


A proximal or mid-shaft fracture that has not broken the skin or become dislocated is treated immediately with rest, ice, compression, and elevation. Rest from activity lasts for several days until the pain and swelling go away. A cast is generally not required for simple fractures. However, it is important to see your doctor if you suspect a fracture, as they may recommend crutches or place you in a walking boot to help reduce your pain. Fractures of the distal fibula, or lateral malleolus, are more complex because ligaments attach here, and because stability of the ankle joint is crucial to any weight-bearing activity. Severe, dislocated, or displaced fractures to this area often require surgery to insert plates and/or screws. It is very important that you see a doctor if you suspect a fracture to this area. Stress fractures are treated with rest from activity for 14 days, and the use of crutches is suggested to reduce pain while walking. After this period, return to activity is based on the patient's pain level. Non weight-bearing activities such as swimming, stationary cycling, or upper body workouts are encouraged to prevent muscle loss. With stress fractures, full return to activity should be accompanied by a change in the training method which caused the fracture.


Healing time will vary depending on the site, type, and severity of the fracture, but typically takes 4 to 6 weeks. If surgery, or casting due to a compound or dislocated fracture is required, the healing time may be longer.