Question
A 24 year old snowboarder lands a jump badly. He has lateral ankle pain, and his radiographs were reported as normal.
- What does the CT show?
- Why is this injury missed?
- Outline management.
Answer
CT
- Fracture of the lateral process of the talus (snowboarder’s fracture)
- Involves the posterior subtalar joint and the talofibular articulation
- Mechanism is axial load with dorsiflexion and eversion or external rotation
Missed diagnosis
- Mimics a lateral ankle sprain
- Tender just below the tip of the lateral malleolus
- Seen on the mortise view, often subtle
- CT for persistent pain after a sprain in snowboarders
Hawkins classification
| Type | Description |
|---|---|
| I | Simple fracture, two fragments |
| II | Comminuted |
| III | Chip fracture of the anteroinferior process |
Management
- Undisplaced fragments, cast non weight bearing for 6 weeks
- Displaced over 2 mm with a large fragment, ORIF
- Comminuted fractures, excision of fragments
- Untreated fractures cause subtalar arthritis and nonunion
Related pages
Author Contributions
Orthofracs team
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.