Ankle fractures are common injuries that result from low energy twitst or falls. The ankle is divided into two main areas: Medially around the inside part of the ankle and laterally around the outside part of the ankle. There are two bony projections from each side of the ankle which can be injured and treatment depends on the stability of joint and whether the cartilage surface is intact. The bony projections are called malleoli (singular malleolus) so we describe the fractures in terms of which malleoli are broken.
The most common type of fracture is called a lateral malleolar fracture; this involves the fibula on the outer portion of the ankle. Most of these are low energy injuries which can be treated successfully with cast immobilization followed by protected weight bearing in a removal cast boot. If the talus (the square shaped bone at the top of the foot) is out of its native position then we usually recommend surgical correction of the alignment and fixation with plates and screws. Many lateral malleolar fractures can be treated without surgery but need to be immobilized in a cast or cast boot for 6 weeks to ensure the bone heals properly.
Medial malleolus fractures are a result of an eversion injury and are less common than lateral malleolus fractures. These fractures typically occur during sporting activities such as soccer and football or stepping off an uneven surface such as a curb. The diagram below show a medial sprain of the ankle, but the mechanism for a medial malleolar fracture is identical. Unlike lateral malleolar fractures, most medial malleolar fractures require surgical repair. The reason for this is that many times soft tissue becomes trapped within the fracture and prevents healing of the bone fragments together. After surgery patients remain non-weight bearing for about 4-6 weeks depending on the severity of the soft tissue injury and swelling.
If both bony projections are fractured, these are referred to as “bimalleolar” ankle fractures. In most cases, these fractures are unstable and should be treated surgically unless there are other factors which would prevent surgical treatment. Surgery may be done as an outpatient procedure to re-align the bones of the ankle and hold them with plates and screws.
Trimalleolar fractures are high energy injuries in which both the lateral and medial malleolus are fractured as well as part of the end of the tibia called the posterior malleolus. These are often associated with a dislocation of the ankle at the time of the injury. These fractures are very unstable and because the soft tissue injury is pretty severe, they frequently necessitate waiting 5-10 days before proceeding with surgery to let the area around the ankle “cool off”. Doing the surgery too soon can result in wound problems and infection. Unlike other ankle fractures, the surgery is more involved and patients usually stay in the hospital overnight for pain control.
The last type of ankle fracture is called a syndesmosis disruption. Although it is technically a disruption of the ligament between the two bones of the ankle joint, it behaves clinically like an ankle fracture. The mechanism is similar to a medial malleolar fracture in that the foot is everted at the time of the injury but instead of a fracture of the medial malleolus, the deltoid ligament (a strong triangular ligament on the medial side of the ankle) tears and the fibular shaft fractures several inches above the ankle joint. This fracture requires surgery to repair the ligaments between the tibia and fibula, and failure to recognize and repair these types of fractures leads to long term instability and pain in the ankle.
Most patients will have a splint on their ankle after surgery. The splint allows some swelling of the ankle without damaging the skin or tissue around your surgery site. Patients return to the office after about 10-14 days and we covert the splint to a regular short leg cast.
After the cast comes off many patients complain of stiffness and swelling in the ankle and foot. This is normal and represents your body’s repsonse to the stress of walking again. During this time exercises and physical therapy may be started to allow some improvement in motion. Total healing time takes 6-8 months and the ankle stays swollen to some extent for up to one year. The screws and plates can irritate the ankle and in those cases we recommend removal of the plates and screws after 12 months. This is a short outpatient surgery and the use of crutches or protected weight bearing after surgery is not indicated.
For patients bothered by the persistent swelling, one solution is to use a compressive stocking such as TED. hose. You should put the stocking on first thing in the morning and take it off at the end of the day. This can make a noticeable difference in swelling and we encourage patients to start using TED hose as soon as they are out of the cast and have their stitches out.
For more information about the surgery and what to expect during and after your surgery (if you are going to have your ankle surgically treated) look at the link below for ankle surgery instructions. It has additional information about when, where and how that you may forget to ask in clinic