Question
A 13 year old girl twists her ankle while skateboarding. Radiographs show a fracture through the distal tibial epiphysis on the AP view and a metaphyseal fragment on the lateral view.
- What is the injury and why does it occur at this age?
- How would you investigate it?
- What are the indications for surgery?
Answer
Injury
- Triplane fracture, a transitional fracture with fracture lines in the sagittal, axial and coronal planes
- Appears as Salter-Harris III on the AP view and Salter-Harris II on the lateral view (IV in three dimensions)
- Occurs as the distal tibial physis closes from central to medial to lateral over about 18 months
- Tillaux fracture is the related avulsion of the anterolateral epiphysis by the AITFL
Investigations
- AP, lateral and mortise radiographs
- CT to define the fracture planes, number of fragments and articular step
- Look for an associated fibular fracture
Indications for surgery
- Articular step or gap over 2 mm after closed reduction
- Fragments are reduced with internal rotation of the foot
- Closed or open reduction and fixation with epiphyseal and metaphyseal screws parallel to the physis
- Growth disturbance is uncommon because the physis is near closure
- Articular incongruity risks early arthritis
Related pages
Author Contributions
Orthofracs team
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.