The ankle joint is composed of three bones: the tibia, fibula, and talus which are articulated together. The ends of the fibula and tibia (lower leg bones) form the inner (medial) and outer (lateral) malleolus, which are the bony protrusions of the ankle joint that you can feel and see on either side of the ankle. The joint is protected by a fibrous membrane called a joint capsule, and filled with synovial fluid to enable smooth movement.
Ankle injuries are very common in athletes and in people performing physical work, often resulting in severe pain and impaired mobility. Pain after ankle injuries can either be from a torn ligament and is called an ankle sprain or from a broken bone which is called an ankle fracture. Ankle fracture is a painful condition where there is a break in one or more bones forming the ankle joint. The ankle joint is stabilized by different ligaments and other soft tissues, which may also be injured during an ankle fracture.
Ankle fractures occur from excessive rolling and twisting of the ankle, usually occurring from an accident or activities such as jumping or falling causing sudden stress to the joint.
With an ankle fracture, there is immediate swelling and pain around the ankle as well as impaired mobility. In some cases, blood may accumulate around the joint, a condition called haemarthrosis. In cases of severe fracture, deformity around the ankle joint is clearly visible and the bones may protrude through the skin.
Types of Fractures
Ankle fractures are classified per the location and type of ankle bone involved. The different types of ankle fractures are:
- Lateral Malleolus fracture in which the lateral malleolus, the outer part of the ankle is fractured.
- Medial Malleolus fracture in which the medial malleolus, the inner part of the ankle, is fractured.
- Posterior Malleolus fracture in which the posterior malleolus, the bony lip at the back of the tibia, is fractured.
- Bimalleolar fractures in which both lateral and medial malleolus bones are fractured
- Trimalleolar fractures in which all three lateral, medial, and posterior bones are fractured.
- Syndesmotic injury, where the ligaments joining the fibula to the tibia are ruptured.
The diagnosis of the ankle injury starts with a physical examination, followed by X-rays and sometimes a CT scan of the injured area for a detailed view. Usually it is very difficult to differentiate a broken ankle from other conditions such as a sprain, dislocation, or tendon injury without having an X-ray of the injured ankle. In some cases, pressure such as weight-bearing is applied to the ankle and then special X-rays are taken. This procedure is called a stress test. This test is employed to check the stability of the fracture to decide if surgery is necessary or not. In complex cases, where detailed evaluation of the ligaments is required an MRI scan is recommended.
Immediately following an ankle injury and prior to seeing a doctor, you should apply ice packs and keep the foot elevated to minimize pain and swelling.
The treatment of ankle fracture depends upon the type and the stability of the fractured bone. Treatment starts with non-surgical methods. All ankle fractures need to be re-aligned to prevent damage to the skin overlying the bony prominences of the ankle. In cases where the fracture is unstable and alignment cannot be obtained or maintained in a plaster, surgical methods are employed.
In non-surgical treatment, the ankle bone is realigned and special splints or a plaster cast is placed around the joint, for 8 - 10 weeks.
With surgical treatment, the fractured bone is accessed by making incisions over the ankle area that has been fractured and then specially designed plates are screwed onto the bone, to realign and stabilize the fractured parts. The incisions are then sutured closed and the operated ankle is immobilized with a splint or cast.
After ankle surgery, you will be instructed to avoid putting weight on the ankle by using crutches while walking for up to six weeks. Some fractures are stable and you can walk on them.
Physical therapy of the ankle joint will be recommended by the doctor. After 2-3 months of therapy, the patient may be able to perform their normal daily activities.
Risks and Complications
Risks and complications that can occur with ankle fractures include improper casting or improper alignment of the bones which can cause deformities and eventually arthritis. In some cases, pressure exerted on the nerves can cause nerve damage, resulting in pain.
Rarely, surgery may result in incomplete healing of the fracture, which requires another surgery to stimulate healing. This may require bone grafting – a procedure where healthy bone is taken from somewhere else (usually from the pelvic bone at your waist) and this bone is then placed around the bone that is not healing.