The ankle joint is a unique structure that depends on perfect alignment of the bones for normal function. Although the ankle moves in an up and down direction (called dorsiflexion and plantarflexion), there is very subtle movement with twisting, called rotation. In order for the ankle to work efficiently, the bones need to line up perfectly in the socket, which is called the mortise.
Ankle fractures range from relatively minor twisting injuries to those associated with violent disruption of the ankle. There are two different mechanisms of injury that have different effects on the structure of the ankle:
- A twisting mechanism and the body rotates around the foot
- A crushing type mechanism that impacts the foot
The twisting type of injuries are far more common, and although there is less likelihood of damage to the cartilage, the bones that make up the ankle joint must nonetheless be carefully re-aligned. The second type of injury that
occurs from a fall from a height, or in a motor vehicle accident, is usually far more serious and often associated with cartilage damage.
The ankle consists of:
- Inner aspect of the tibia (the medial malleolus)
- Outer aspect of the ankle (the fibula)
- Bone underneath the ankle (the talus)
There are many different varieties and grades of severity of ankle fractures. These may involve only the medial malleolus, only the fibula, or both bones (which is called a bi-malleolar fracture). At times the talus may completely pop out of the ankle joint associated with the fracture, which is called a fracture dislocation.
Ankle fracture symptoms include:
- Inability to bear weight
An orthopedic surgeon specializing in foot and ankle injuries can diagnose an ankle fracture by conducting a physical exam of the foot and ankle. X-rays and MRIs may be performed to help determine the extent of the injury.
If the shape and anatomy of the ankle are not accurately restored, the cartilage lining of the ankle will be disturbed. This will inevitably lead to arthritis. Think of arthritis as a wearing away of the grisel lining of the bone. Imagine the end of a chicken bone which is lined with cartilage. Every joint in the body is lined with cartilage and loss of the cartilage leads to the development of arthritis. Therefore, the goal of treating all ankle fractures is to re-position the bones to prevent the occurrence of arthritis. Some minor ankle fractures can be treated in a boot or a cast without surgery.
The majority of ankle fractures, however, do require operative treatment. Surgery is performed with incision(s) on one or both sides of the ankle. Screws and/or a metal plate are inserted into the medial malleolus and the fibula in order to accurately restore or reduce the fracture alignment.
Following surgery, a bandage with plaster is applied to the ankle. The bandage remains until the stitches are removed (usually about two weeks). At that time exercise activities are initiated. No walking on the ankle is permitted for approximately six weeks. At that time protective walking (with a removable boot or brace) may be allowed. Physical therapy exercises, swimming and biking are important parts of the recovery process. They strengthen the leg and develop movement of the ankle.
If the ankle is not repaired correctly or does not heal well, arthritis and deformity of the ankle can occur. Some of these patients will have no other option but to have the ankle surgery re-done. Dr. Mark Moss has developed techniques for salvaging very severe deformities of the ankle after unsuccessful fracture treatment.