There are a variety of fractures which can occur about the foot and ankle. When an athlete is unable to bear weight following an injury, the presence of a fracture should be considered.
Athletes generally present after an acute injury. The individual mechanisms of injury are considered with a description of each fracture type below. In general, an inability to bear weight is very suggestive of a fracture.
An inability to bear weight, localised tenderness and significant swelling are all characteristic findings. When there is significant displacement, an assessment of neurovascular status is needed.
Fractures are generally readily seen on x-rays. Where there is uncertainty, an athlete may be treated for a period of 7-10 days and then have a repeat x-ray. Alternatively, CT imaging or MRI can be used to document the injury.
Weber A fracture
The fracture line is below the ankle joint level. This is a stable injury.
Weber B fracture
The fracture line extends to involve the ankle joint line. This is potentially unstable.
Weber C fracture
This fibular fracture is above the joint line and is unstable.
Remember to palpate the proximal fibula to help identify this injury.
Fibula stress fracture
Subtle periosteal reaction may be the only evidence of a stress fracture.
In general terms, these fractures need prompt reduction and a period of immobilisation. When the fracture is unstable, or involves the joint surface, early surgical management (open reduction and fixation) is advised. Any signifant deformity requires prompt reduction. This should not be delayed. Any change in neurovascular status requires immediate surgical management.
- Weber classification
- This classification scheme is based on the level of the fracture in relation to the joint mortise of the distal fibula. There are three grades which are based on their radiological appearance.
- Type A fractures are avulsion fractures found below the mortise. These are stable and can be treated with casting.
- Type B fractures are spiral fractures that start at the level of the mortise. This type of fracture occurs secondary to rotation. These fractures may be stable or unstable depending on ligamentous injury or associated fractures on the medial side. Tenderness to palpation around the medial ankle and/or diastasis on plain films may suggest that surgery is required.
- Type C fractures are above the level of the mortise and disrupt the ligamentous attachments between the fibula and the tibia distal to the fracture. These fractures are unstable and require open reduction and internal fixation.
- Maisonneuve fracture
- A Maisonneuve fracture is a spiral fracture of the proximal fibula that is associated with injury to the distal tibio-fibular syndesmosis and the interosseous membrane. In addition, there is an associated fracture of the medial malleolus or rupture of the deep deltoid ligament. Always palpate the proximal fibula when assessing an athlete with an injured ankle. A high index of suspicion is needed. Order an x-ray of the proximal fibula when pain is detected with palpation.
- Lateral process of talus fracture
- This injury is most frequently seen in snowboarders, but can occur in football. Different mechanisms have been reported. In snowboarding, there appears to be axial loading of a dorsiflexed and everted ankle.7 In other athletes, it is more likely to be more of an avulsion-type mechanism with inversion of a dorsiflexed ankle. Physical examination reveals tenderness directly below the lateral malleolus. This type of fracture is best seen on the mortise view although CT or MRI may be needed to confirm the diagnosis. An acute, undisplaced fracture can be treated with immobilisation. Injuries with more than 2mm displacement or that are comminuted can be treated with either excision or with open reduction and internal fixation.
- Anterior process of calcaneus fracture
- This is another source of ongoing pain following an ankle injury. The injury occurs after a combination of plantar flexion and adduction and is caused by avulsion of the bifurcate ligament. 8 The best x-ray for this injury is an oblique view of the mid-foot. There is a better prognosis with early recognition and management of these, and all midfoot injuries. Large fractures may involve the calcaneocuboid joint and every effort should be made to reduce these anatomically.
- Stress fractures
- A number of stress injuries may cause pain around the ankle. The most common is a distal fibular stress fracture, but stress fractures of the distal tibia also occur and should be considered. A navicular stress fracture causes very diffuse pain which can be felt in the ankle and is considered a high-risk stress fracture as it can take a prolonged period to heal.9 This typically requires a period of non-weight-bearing rest; surgical fixation may be necessary in selected athlete cases.10 Stress fractures should be considered in all cases where there is an insidious onset of pain, localised tenderness that is accompanied with pain, apprehension, or both with hopping.
Dr Pieter D'Hooghe