foot ankle
Ankle Fractures (Weber/AO Classification)
intermediate
6 min
28 marks
6 questions
Clinical Scenario
A 52-year-old woman presents to the emergency department following a twisting injury to her right ankle while walking down stairs. She heard a "crack" and was unable to weight-bear. On examination, there is significant swelling around the ankle with tenderness over both malleoli. The foot is neurovascularly intact. AP, lateral, and mortise radiographs reveal a displaced fracture of the distal fibula at the level of the joint line with a transverse medial malleolar fracture. The medial clear space is widened to 6mm.
AP and lateral radiographs of the ankle demonstrating a Weber B bimalleolar ankle fracture. The fibular fracture is at the level of the syndesmosis (trans-syndesmotic). There is an associated transverse medial malleolar fracture. The mortise view shows lateral talar shift with increased medial clear space (>4mm) indicating deltoid ligament injury or medial malleolar fracture. The posterior malleolus is intact on lateral view.
Image source: Open Access medical literature (NIH/PubMed Central) • CC-BY License
Questions
Question 1 (4 marks)
Describe the classification systems for ankle fractures.
Question 2 (5 marks)
How do you assess stability of an ankle fracture?
Question 3 (6 marks)
Describe the surgical approach and fixation principles.
Question 4 (5 marks)
When do you address the syndesmosis and posterior malleolus?
Question 5 (4 marks)
What are the complications of ankle fractures?
Question 6 (4 marks)
Discuss outcomes and special circumstances.
Exam Day Cheat Sheet
Must Mention
- •Weber: A (below), B (at), C (above) syndesmosis
- •Medial clear space >4mm = unstable
- •SER most common mechanism
- •Syndesmosis: fix Weber C, stress test Weber B
- •Posterior malleolus: fix if >25% or unstable
- •Fix fibula first (restores length/rotation)
Common Pitfalls
- •Missing Maisonneuve
- •Not stress testing Weber B
- •Fixing medial before fibula
- •Wrong ankle position for syndesmosis
- •Missing posterior malleolus
- •Not checking mortise alignment