ANKLE FRACTURES. Shoe, Monte Carlo, gelatin silver print, Helmut Newton, 1983

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1 ANKLE FRACTURES Shoe, Monte Carlo, gelatin silver print, Helmut Newton, 1983 A cause may be inconvenient - but it is magnificent. It s like champagne - or high heels - one must be prepared to suffer for it! Arnold Bennett

2 ANKLE FRACTURES Introduction Ankle fractures are a common presentation to the Emergency Department. In severely displaced injuries, urgent reduction is important, even before radiological confirmation of injury. Classification There are a number of classification systems that relate to fractures of the ankle. The Danis-Weber classification is the probably most useful, as it is simple to understand and has relevance to treatment. The Danis-Weber classification classifies ankle fractures according to the level of the fibula component of an ankle fracture, with respect to the syndesmosis. The syndesmosis refers to the complex of ligaments that bind the lower tibiofibular joint. For practical purposes when reading an x-ray, the syndesmosis is taken as the ankle joint line, ie the tibio-talar joint. There are 3 main types of Weber fracture, Type A, B and C. Examples are shown in the diagram below and actual radiographs in Appendix 1

3 Weber Type A Ankle Fracture Description: Type A: is a fibular fracture below the level of the syndesmosis (ie joint line) A1 A2 A3 Isolated In association with a fracture of the medial malleolus or rupture of the deltoid ligament. In association with a posteromedial fracture of the lower tibia. Ligament Disruption: Usually no associated ligamentous (syndesmosis) injury. Usual Mechanism: Internal rotation and adduction. Weber Type B Ankle Fracture Description: Type B: is a fibular fracture at the level of the joint line. B1 B2 B3 Isolated. In association with a fracture of the medial malleolus or rupture of the deltoid ligament. In association with a medial injury and a fracture of the posterolateral tibia. Ligament Disruption: No or partial associated ligamentous injury. Usual Mechanism: External rotation. Weber Type C Ankle Fracture Description: Type C: is a fibular fracture above the level of the joint line. C1 Isolated diaphyseal fibula fracture.

4 C2 C3 Complex diaphyseal fibula fracture. Proximal fracture of the fibula. Ligament Disruption: Significant or total associated ligamentous injury. Usual Mechanism: Adduction or abduction with external rotation. Complications Most fractured ankles are uncomplicated, and management will be straightforward. Complications may occur in more severe injuries and may include: 1. Compound injuries: With subsequent risk of osteomyelitis. 2. Vascular compromise with significantly displaced injuries (uncommon). 3. Skin compromise with significantly displaced injuries. There can be significant skin ischaemia, in this region with severely displaced fractures. Unless there is timely reduction in these circumstances there is a risk of skin necrosis. 4. Delayed, mal and non-union, as with any fracture not adequately treated initially. 5. Secondary degenerative osteoarthritis Clinical Assessment Important points of history 1. Mechanism/ circumstances of the injury. 2. Last ate (if severe injury that may require ORIF). 3. Past history/ co-morbidities/ allergies/ medications. Important points of examination 1. Check neurovascular status.

5 2. Skin compromise (if displaced). Severe compound fracture-dislocation of the right ankle. Note the pointed tenting of the skin at the apex of the wound. This is from underlying the tibia and puts the overlying skin at risk of ischaemic necrosis, making reduction of the deformity urgent. 3. Check if the injury is compound. 4. Check ability to bear weight (in more minor injuries). 5. Carefully check the exact points of tenderness; a common mistake is to assume a lateral malleolus fracture with lateral ankle/foot pain and not specifically check the base of the fifth metatarsal for tenderness (and the injury is in fact a fractured base of fifth metatarsal). Investigations Plain Radiology Plain radiography will readily diagnose the injury in most cases. A-P and lateral views are taken. Specific foot views should be requested if there is tenderness over the base of the fifth metatarsal, or if there is any doubt as to the exact location of pain/tenderness. The Ottawa ankle rules have been established to assist in determining whether or not a plain x-ray is necessary (see separate guidelines for a full description of these).

6 CT scan This is not required in most cases however may be indicated when: Plain radiography is inconclusive, but clinical suspicion for fracture remains high. There is a complex injury that requires further definition for the planning of operative repair. Management 1. Analgesia, as required. 2. For severely displaced fractures: These should be reduced urgently if there is skin or neurovascular compromise, even before radiology has been performed. 3. Compound injuries should receive timely IV antibiotics. 4. Non-displaced fractures: These may be treated with a below knee plaster. 5. Surgery: More severe injuries and displaced fractures will generally require ORIF. In general terms: The Danis-Weber classification is based on the premise that the higher the fibular component of an ankle fracture, the greater will be the associated syndesmotic (lower tibio-talar ligament) disruption. The greater the syndesmotic injury the more unstable the injury will be and the greater will be the need for surgical intervention. Appendix 1:

7 THE DANIS-WEBER CLASSIFICATION OF ANKLE FRACTURES Weber Type A Ankle Fracture, (the fracture line lies below the line of the ankle joint). Weber Type B Ankle Fracture in a 35 yr old male, (the fracture line lies at the level of the ankle joint).

8 Weber Type C Ankle Fracture, the fracture line lies above the level of the ankle joint.

9 X-ray high heeled shoe by Karl Lagerfeld, Helmut Newton: gelatin silver print, (Sold at Christie s New York October 17, 2006: $42,000). References 1. Stiell IG, Greenberg GH, McKnight RD, et al: A study to develop clinical decision rules for the use of radiography in acute ankle injuries. Ann Emerg Med 1992; 21: Stiell IG, Greenberg GH, McKnight RD, et al: Decision rules for the use of radiography in acute ankle injuries: Refinement and prospective validation. JAMA 1993: 269: Broomhead A, Stuart P: Validation of the Ottawa Ankle Rules in Australia. Emergency Medicine vol. 15 no 2 April 2003, p Dr J. Hayes Reviewed August 2012