Classification of Ankle Injuries: Foundational Concepts
Ankle injuries include ligamentous sprains, malleolar fractures, fracture-dislocations, syndesmotic injuries, osteochondral injuries, tendon disruptions and open or neurovascular injuries. For examination purposes, classification should be based on the tissue injured, mechanism of injury, anatomical level of fracture, stability of the ankle mortise and presence of dislocation or soft-tissue compromise. The central treatment principle is to restore and maintain a congruent ankle mortise, because even small persistent talar displacement markedly alters contact mechanics and may lead to post-traumatic arthritis.
The ankle joint is formed by the distal tibia and fibula embracing the talar body. Stability depends on the medial malleolus and deltoid ligament, the lateral malleolus and lateral collateral ligament complex, the distal tibiofibular syndesmosis, the capsule and the congruent talar dome. The lateral ligament complex comprises the anterior talofibular ligament, calcaneofibular ligament and posterior talofibular ligament. The anterior talofibular ligament is most commonly injured during inversion with plantar flexion.
Initial Clinical Classification
Before applying a named fracture classification, the injury should be described clinically as:
- Closed or open: an open wound communicating with the fracture requires urgent antibiotics, tetanus prophylaxis, sterile covering and operative debridement.
- Stable or unstable: stability depends on preservation of…