System used to describe ankle fracture/sprains. External rotation injuriesÑ1st degree, transsyndesmotic fibula fracture [1st degree (alternate), anterior tibiofibular ligament rupture]; 2nd degree, deltoid ligament rupture [2nd degree (alternate), medial malleolus avulsion]; 3rd degree, distal tibial and fibula fracture with external rotation. Abduction injuriesÑ1st degree, transverse medial malleolus fracture; 2nd degree, deltoid ligament rupture or medial malleolus fracture with distal fibula fracture; 3rd degree, distal tibia fracture with lateral displacement of medial malleolus. Adduction injuriesÑ1st degree, fibular malleolus avulsion; 2nd degree, fibular malleolus avulsion with vertical tibial shaft fracture; 3rd degree, supramalleolar fracture of fibula and tibia with medial displacement. Long-axis compression fracturesÑ1st degree, marginal fracture of distal tibial plate; 2nd degree, comminuted tibial plafond fracture; 3rd degree, Gosselin V-fracture or T-Y fracture.