The ankle is made up of three bones: the tibia (large leg bone), the fibula (smaller leg bone), and the talus (first foot bone between the heel and the leg). Each of these bones has critical parts that work to hold the ankle together while still allowing motion. The bony parts are connected to one another by ligaments. When surgeons think about ankle fractures, we think in terms of these bony parts and ligaments. The picture in Figure 4 shows a patient with a fractured ankle that is dislocated and pushing against (tenting) the skin.
Mechanism and Epidemiology
Ankle fractures occur in people of all ages and are among the most common injuries treated by an orthopaedic surgeon. Ankle fractures most often occur from a simple twist and fall, as can happen on a wet floor, a grassy hill, on stairs, or off a curb. Because there are so many bony parts and ligaments, sometimes only 1 or 2 parts are injured, although many parts can be injured.
The bony parts of the fibula and tibia are called malleoli (singular = malleolus). The most common malleolus fracture happens at the fibula. It is called a lateral (outside of the ankle) malleolus fracture and is depicted in Figure 5. Lateral malleolus fractures are often stable and can be treated without surgery. When a lateral malleolus fracture is accompanied by a sprain of the ligament on the inside of the ankle (the deltoid ligament), your injury may be unstable and may require surgery. This could mean a plate and screws, just screws, a nail, or just suture.
The worse the injury, the more likely it will be unstable. To best describe the degree of injury, we describe ankle fractures according to the number of malleoli fractured. When 2 malleoli are fractured, the injury is called a bimalleolar ankle fracture and when 3 malleoli are fractured, the injury is called a trimalleolar ankle fracture. Examples are shown in Figure 6.
Ankle fractures are typically very painful and obvious if there is a dislocation (ankle joint out of place) or an open wound. Most often, the emergency room doctor will examine your foot and ankle for sensation, blood flow, and your ability to move your toes. After this initial exam, x-rays are usually performed to help define the bony injury and some form of splint may be applied. If the ankle is dislocated, you may need a “reduction,” which means the doctor will manipulate the foot and ankle back in to position with his or her hands, and then apply a splint or boot. Reduction is usually done after pain medications have been given, and these can include oral, intravenous, or local pain medications.
If the ankle is not dislocated and it is not obvious if the fracture is stable or not, a stress x-ray may be needed. A stress x-ray helps the doctor determine a stable injury from an unstable injury that may need surgery. A stress x-ray is depicted in Figure 3B, and shows instability when compared to the image in Figure 3A. After reduction and splint application, your healthcare provider will explain if he or she thinks surgery is needed, and will most likely refer you to an orthopaedic surgeon for evaluation and further treatment. If surgery is needed, it is commonly done within 5 to 10 days, but may be delayed up to 3 weeks in some cases if your ankle is too swollen. You may be sent home with crutches or some other form of assistive device to help keep weight off your ankle. More severe injuries may require hospitalization and either definitive surgery or a temporary surgery (external fixator) to hold the fractured ankle in place until swelling goes down.
Simpler ankle fractures can be treated with early weight-bearing in a protective boot. Examples include isolated lateral malleolar fractures without deltoid sprain and some nondisplaced medial malleolar fractures. Unstable injuries benefit from surgery to provide stability to the ankle joint as a whole and to the individual fractured parts. By repairing the ankle surgically, we can confidently allow early range of motion exercises to reduce stiffness and disability that can result from prolonged treatment with a cast or splint. Surgical incisions around the ankle are at higher risk for wound complications than skin in other areas. This is because there is very little tissue (fat, muscle, fascia) between the skin and the bone around the ankle. Fractures with more injured parts may be more swollen and may require more incisions. As such, your doctor will determine the best timing for surgery and the best location for skin incisions to minimize your risk. Examples of non-operatively and operatively treated fractures are seen in Figure 7.
After surgery, you will most likely be in a plaster splint or fracture boot. This is to protect your skin and surgical incisions while supporting your ankle in a neutral position to prevent stiffness in your calf. Like the original injury, surgery produces swelling and swelling can put tension on your wounds. Minimizing that tension can help reduce the risk of infection and also helps with pain. To reduce swelling, you should try to keep your foot at or slightly above the level of your heart as much as possible. You should not bear weight on your foot during this early, critical phase of healing. Smoking has been shown to slow healing after ankle fracture surgery, so if you smoke, you should not do so at this time. Your surgical team will usually see you to follow-up around 7 to 14 days after surgery. You can expect to have skin sutures and staples removed typically between 10 to 14 days after surgery. You may be instructed in home exercises at this point, and given a fracture boot to allow easy removal for bathing and range of motion exercises. Depending on your needs, your surgical team may choose to initiate formal physical therapy at this time or delay physical therapy until a later date. For best healing, it is important to follow instructions from your surgeon regarding your post-operative care.
While most simple ankle fractures heal very well, more significant injuries may have long-term issues and can include stiffness, soreness, and an inability to regain full, pre-injury motion and function. You may require several months of physical therapy to be able to return to your prior activities. Your injured ankle may always feel and move a little differently compared to uninjured ankle.
While most ankle fractures heal well, some may develop post-traumatic arthritis, with increasing pain and stiffness. This complication can occur with or without surgery, and you should discuss this with your surgeon to determine your treatment options. For some older people, ankle replacement may be an option if symptoms get too severe. In younger patients, your doctor may recommend removal of the hardware, fusion, or other surgery.
Babar Shafiq, MD
Edited by the OTA Patient Education Committee
All x-rays and pictures taken from the personal collections of Dr. Shafiq and Christopher Domes, MD