In adults, ligaments are weaker than bone. The anterior tibiofibular ligament in adults is torn first in the majority of ankle fractures. In children, the growth plate is weaker and can become avulsed. An avulsion injury is rarely seen in adults because the ligament gives out instead of avulsing the bone.
Tillaux fractures occur in adolescents, usually around 12-15 years of age. These fractures occur after the middle and medial parts of the epiphyseal plate closes and before the lateral part is closed. The lateral part of the growth plate remains open, which could allow for an avulsion fracture at the attachment of the anterior tibiofibular ligament. An external rotating force causes an avulsion of the distal tibial epiphyseal plate anterolaterally. Further lateral rotation displaces the fracture and may be associated with fracture of the lateral malleolus. 
Treatment
If the fracture is displaced 2mm or more, the surgeon will want to perform a reduction and fixation. This fixation can be done from either lateral to medial or medial to lateral. Wagstaffe’s fracture is an avulsion of the anterior portion of the fibula by the anterior tibiofibular ligament. This type of 
injury is associated with supination external rotation type injuries (Lauge-Hangen) and typically occurs in adult patients.
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