This is a classic case of Tillaux fracture of the distal tibia. The mean age for Tillaux fracture is 14 years old for male and 12 years old for female. The distal tibia physis closure begins centrally in a region known as "Kump's bump". The central and posteromedial physis typically fuse before the anterolateral physis. Ankle external rotation injury can result in avulsion injury to the osseous attachments of the anterior tibiofibular ligament resulting in Tillaux fracture. 

When reporting Tillaux fracture is is vital to assessment the fracture on both the coronal and sagittal reformatted images and report the degree of fracture displacement. Typically more than 2 mm displacement of the fracture fragment requires surgical intervention. Lastly, assessment of the distal fibula is vital as occasionally there will be an accompanying osseous avulsion fracture as demonstrated in this case.