What is Fibula Fractures?
Fractures of the tibia and fibula, the two long bones in the leg, are a common injury, but we don’t often hear about isolated fractures of the fibula. This might be because most fractures of the fibula do not require surgery, unlike fractures of the lateral malleolus, a part of the fibula at the ankle which is considered a different type of fracture with different treatment methods. The following content will explain about fibula fractures that occur above the ankle and how they are treated.
The fibula is the smaller and thinner of the two long bones in your leg, and unlike the tibia, it doesn’t bear a lot of weight. The fibula is situated on the back and outer edge of your leg. It starts just behind the tibia at the knee and runs down the side of your leg to the ankle.
The fibula connects to the tibia through a connective tissue called the interosseous membrane. This connection has little to no movement.
Parts of the fibula include the head (top part), the neck (just below the head), the shaft (thin, long section), and the lateral malleolus (part at the ankle). This piece will focus on the shaft, which is found between the neck and the lateral malleolus. At this area, multiple leg muscles such as the extensor digitorum longus, extensor hallucis longus, peroneus tertius (all in the front compartment), peroneus longus, peroneus brevis (on the side), soleus (back, upper part), tibialis posterior and flexor hallucis longus (back, lower part) originate. This part of the fibula is shown as a triangular shape because of where these muscles are attached.
The superficial peroneal nerve is responsible for controlling the lateral muscles of the leg that help in moving your foot to the side or pointing it down slightly. If this nerve gets damaged, it may cause problems in carrying out these movements. This nerve also helps in feeling sensations on the top part of the foot.
The deep peroneal nerve controls the front leg muscles and is responsible for lifting the foot and toes upward. Damage to this nerve often results in a condition known as foot drop, which causes the inability to lift the foot upward. This nerve also helps in feeling sensations between the first and second toe.
What Causes Fibula Fractures?
It’s very rare to see a fracture in the fibula (a bone in the lower leg) with no other injuries to surrounding bones or ligaments. Usually, these fibula fractures happen because of a direct injury to the leg. This could be due to a fall, a hit, or a blunt trauma like a sports accident or a car crash. Another possible cause is gunshot wounds. Essentially, for a fibula fracture to happen on its own, there typically needs to be a direct force to it.
Risk Factors and Frequency for Fibula Fractures
Isolated fractures of the fibula, the smaller of the two bones in your lower leg, are quite rare, and not much information exists on how often they occur. Tibia fractures, on the other hand, which involve the larger bone in your lower leg, are most common in young males and elderly females. It’s believed that most isolated fibula fractures occur in a younger group of people. This is likely because these injuries often occur in young athletes, particularly those who participate in contact sports, and in individuals involved in car accidents. Specifically, those who are driving, and pedestrians struck by vehicles, are at a high risk.
Signs and Symptoms of Fibula Fractures
If you’ve recently experienced a blow to your leg and find it painful to touch, especially on the outer side where the fibula bone is located, you might have a fibula shaft fracture. This type of fracture is uncommon and usually results from direct damage to the leg. Doctors will also look for skin injuries like cuts, scrapes, or bruises that could indicate a leg injury. They’ll check your leg thoroughly, including assessing the movement of joints near the injury to exclude any joint issues. The pain you’ll feel is often sudden and sharp, rather than something that builds up slowly or feels like nerve pain such as a burning or shooting sensation.
Testing for Fibula Fractures
If you have a suspected fracture in the shaft of your fibula (the smaller bone in your lower leg), doctors will perform a thorough check to make sure that this is the only damaged area. The general rule of thumb in orthopedic evaluations is to assess one joint above and below the injured area. In this case, your doctor will check your knee and ankle as well.
X-rays of your knee and ankle are crucial as they help rule out any hidden fractures. Let’s say the X-ray reveals a fracture at the neck of your fibula, but we don’t see any other fractures in your tibia (the large bone in your lower leg) or elsewhere in the fibula, this points to a specific type of ankle injury called a Maisonneuve fracture.
This kind of injury can’t be classified as an isolated fibula shaft fracture because it also involves the connective tissues (ligaments), and as a result, it needs a different approach to treatment. Similarly, a fracture of the fibula close to the ankle (within about 6 inches) often hints that the tibia may also be injured or the ligaments may be damaged, or it could be both.
Treatment Options for Fibula Fractures
In most cases, isolated fractures of the fibula shaft, which is not a part of the bone that supports weight, don’t require surgery. Instead, patients are usually advised to put as much weight on the affected leg as they can tolerate. Some doctors may also recommend using a walking boot to make it more comfortable.
What else can Fibula Fractures be?
- Osteoid osteoma (a small, benign tumor of the bone)
- Ewing sarcoma (a rare type of cancer affecting bones or the tissue around bones)
- Osteosarcoma (a type of bone cancer that usually affects larger bones)
- Osteomyelitis (infection in the bone)
- Muscle spasm (sudden, involuntary muscle contraction)
- Ankle sprain (injury to the ligaments in the ankle)
- Tendon rupture (a tear in the fibrous tissue that connects muscle to bone)
- Compartment syndrome (serious condition that involves increased pressure in a muscle compartment)
- Nerve entrapment (a condition where a nerve is compressed)
These could be the possible causes of bone or muscle pain, and it’s crucial for the doctor to differentiate between these conditions for an accurate diagnosis and appropriate treatment.
What to expect with Fibula Fractures
People with a solitary fracture in the fibula (the smaller bone located in your leg) usually have good outcomes. This type of injury is often managed with conservative treatments and focused on alleviating symptoms. With this approach, long-term complications are rarely seen and the healing process tends to occur between 6 to 8 weeks, particularly in patients with few or no additional health issues.
Possible Complications When Diagnosed with Fibula Fractures
Though uncommon, complications related to fibula shaft fractures are possible. There have been known instances of damage to the superficial peroneal nerve, a key nerve in the leg. Arterial damage and compartment syndrome, a painful and potentially serious condition caused by pressure buildup from internal bleeding or swelling of tissues, have also been reported in patients with isolated fibula fractures.
If the fracture doesn’t heal properly, it may lead to a nonunion, a condition where the broken ends of a bone fail to grow back together. If symptomatic, the preferred treatment involves the use of a compression plate and a procedure known as autogenous bone grafting. These compression plates, which are used to hold the bone in place while it heals, can usually be left inside the body permanently unless they cause discomfort. They are typically not removed until at least a year has passed.
