The fibula and tibia are the two long bones of the lower leg. The fibula, or calf bone, is a small bone located on the outside of the leg. The tibia, or shinbone, is the weight-bearing bone and is in the inside of the lower leg.
The fibula and the tibia join together at the knee and ankle joints. The two bones help to stabilize and support the ankle and lower leg muscles.
A fibula fracture is used to describe a break in the fibula bone. A forceful impact, such as landing after a high jump or any impact to the outer aspect of the leg, can cause a fracture. Even rolling or spraining an ankle puts stress on the fibula bone, which can lead to a fracture.
Fibula fractures can happen at any point on the bone and can vary in severity and type. Types of fibula fracture include the following:
- Lateral malleolus fractures occur when the fibula is fractured at the ankle
- Fibular head fractures occur at the upper end of the fibula at the knee
- Avulsion fractures happen when a small chunk of bone that is attached to a tendon or ligament is pulled away from the main part of the bone
- Stress fractures describe a situation where the fibula is injured as the result of repetitive stress, such as running or hiking
- Fibular shaft fractures occur in the mid-portion of the fibula after an injury such as a direct blow to the area
A fibula fracture can be due to many different injuries. It is commonly associated with a rolled ankle but can also be due to an awkward landing, a fall, or a direct blow to the outer lower leg or ankle.
Fibula fractures are common in sports, especially those that involve running, jumping, or quick changes of direction such as football, basketball, and soccer.
Pain, swelling, and tenderness are some of the most common signs and symptoms of a fractured fibula. Other signs and symptoms include:
- Inability to bear weight on the injured leg
- Bleeding and bruising in the leg
- Visible deformity
- Numbness and coldness in the foot
- Tender to the touch
People who have injured their leg and are experiencing any of the symptoms should consult a doctor for a diagnosis. The following steps occur during the diagnosis process:
- Physical examination: A thorough examination will be conducted and the doctor will look for any noticeable deformities
- X-ray: These are used to see the fracture and see if a bone has been displaced
- Magnetic resonance imaging (MRI): This type of test provides a more detailed scan and can generate detailed pictures of the interior bones and soft tissues
Bone scans, computerized tomography (CT), and other tests may be ordered to make a more precise diagnosis and judge the severity of the fibula fracture.
Treatment for a fibula fracture can vary and depends greatly on how severe the break is. A fracture is classified as open or closed.
Open fracture (compound fracture)
In an open fracture, either the bone pokes through the skin and can be seen or a deep wound exposes the bone through the skin.
Open fractures are often the result of a high-energy trauma or direct blow, such as a fall or motor vehicle collision. This type of fracture can also occur indirectly such as with a high-energy twisting type of injury.
The force required to cause these types of fractures means that patients will often receive additional injuries. Some injuries could be potentially life-threatening.
According to the American Academy of Orthopedic Surgeons, there is a 40 to 70 percent rate of associated trauma elsewhere within the body.
Doctors will treat open fibula fractures immediately and look for any other injuries. Antibiotics will be administered to prevent infection. A tetanus shot will also be given if necessary.
The wound will be cleaned thoroughly, examined, stabilized, and then covered so that it can heal. An open reduction and internal fixation with plate and screws may be necessary to stabilize the fracture. If the bones are not uniting, a bone graft may be necessary to promote healing.
Closed fracture (simple fracture)
In a closed fracture, the bone is broken, but the skin remains intact
The goal of treating closed fractures is to put the bone back in place, control the pain, give the fracture time to heal, prevent complications, and restore normal function. Treatment begins with the elevation of the leg. Ice is used to relieve the pain and reduce swelling.
If no surgery is needed, crutches are used for mobility and a brace, cast, or walking boot is recommended while healing takes place. Once the area has healed, individuals can stretch and strengthen weakened joints with the help of a physical therapist.
There are two main types of surgery if a patient requires them:
- Closed reduction involves realigning the bone back to its original position without the need to make an incision at the fracture site
- Open reduction and internal fixation realigns the fractured bone to its original position using hardware such as plates, screws, and rods
The ankle will be placed into a cast or fracture boot until the healing process is complete.
After being in a cast or splint for several weeks, most people find that their leg is weak and their joints stiff. Most patients will require some physical rehabilitation to make sure their leg regains full strength and flexibility.
A physical therapist will evaluate each person individually to determine the best treatment plan. The therapist may take several measurements to judge the individual’s condition. Measurements include:
- Range of motion
- Surgical scar tissue assessment
- How the patient walks and bears weight
Physical therapy usually begins with ankle strengthening and mobility exercises. Once the patient is strong enough to put weight on the injured area, walking and stepping exercises are common. Balance is a vital part of regaining the ability to walk unassisted. Wobble board exercises are a great way to work on balance.
Many people are given exercises that they can do at home to further help with the healing process.
Proper treatment and rehabilitation supervised by a doctor increases the chance the person will regain full strength and motion. To prevent fibula fractures in the future, individuals who participate in high-risk sports should wear the appropriate safety equipment.
People can reduce their fracture risk by:
- Wearing appropriate footwear
- Following a diet full of calcium-rich foods such as milk, yogurt, and cheese to help build bone strength
- Doing weight-bearing exercises to help strengthen bones
Fractured fibulas typically heal with no further problems, but the following complications are possible:
- Degenerative or traumatic arthritis
- Abnormal deformity or permanent disability of the ankle
- Long-term pain
- Permanent damage to the nerve and blood vessels around the ankle joint
- Abnormal pressure buildup within the muscles around the ankle
- Chronic swelling of the extremity
Most fractures of the fibula do not have any serious complications. Within a few weeks to several months, most patients make a full recovery and can continue their normal activities.