Classification
Lauge-Hansen Classification
| Classification | Description |
|---|---|
| Supination-Adduction (SA) | ~Transverse avulsion-type fracture of the fibula below the level of the joint or tear of the lateral collateral ligaments ~Vertical fracture of the medial malleolus |
| Supination-Eversion (External Rotation) (SER) | ~Disruption of the anterior tibiofibular ligament ~Spiral oblique fracture of the distal fibula ~Disruption of the posterior tibiofibular ligament or fracture of the posterior malleolus ~Fracture of the medial malleolus or rupture of the deltoid ligament |
| Pronation-Abduction (PA) | ~Transverse fracture of the medial malleolus or rupture of the deltoid ligament ~Rupture of the syndesmotic ligaments or avulsion fracture of their insertions ~Short, horizontal, oblique fracture of the fibula above the level of the joint |
| Pronation-Eversion (External Rotation) (PER) | ~Transverse fracture of the medial malleolus or disruption of the deltoid ligament ~Disruption of the anterior tibiofibular ligament ~Short oblique fracture of the fibula above the level of the joint ~Rupture of posterior tibiofibular ligament or avulsion fracture of the posterolateral tibia |
| Pronation-Dorsiflexion (PD) | ~Fracture of the medial malleolus ~Fracture of the anterior margin of the tibia ~Supramalleolar fracture of the fibula ~Transverse fracture of the posterior tibial surface |
AO Classification of Ankle Fractures
| Type | Subtype | Description |
|---|---|---|
| Type A Fibula Fracture below Syndesmosis (Infrasyndesmotic) | A1 | isolated |
| A2 | with fracture of medial malleolus | |
| A3 | with a posteromedial fracture | |
| Type B Fibula Fracture at Level of Syndesmosis (Transsyndesmotic) | B1 | isolated |
| B2 | with medial lesion (malleolus or ligament) | |
| B3 | with a medial lesion and fracture of posterolateral tibia | |
| Type C Fibula Fracture above Syndesmosis (Suprasyndesmotic) | C1 | diaphyseal fracture of the fibula, simple |
| C2 | diaphyseal fracture of the fibula, complex | |
| C3 | proximal fracture of the fibula |
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.