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Ankle fractures — Ottawa rules and Weber classification
The Ottawa rules decide who needs radiographs after an ankle injury, and the key question in a fracture is joint stability: a stable fibular fracture is treated in a boot with weight-bearing, while an unstable fracture — bimalleolar, with syndesmotic injury or with talar shift — is treated surgically.
Why it matters in the exam
Ankle injury is one of the most common reasons for emergency visits, and questions test two steps. First: whether to image. Under the Ottawa rules, an ankle X-ray is indicated for malleolar-area pain together with tenderness at the tip or back edge of either malleolus over its distal 6 cm, or when the patient cannot take 4 steps both right after the injury and in the department; a foot radiograph is needed for tenderness at the base of the fifth metatarsal or over the navicular. Second: whether the fracture is stable. The Weber classification describes the level of the fibular fracture relative to the syndesmosis: A below it, B at its level and C above it. A Weber A fracture is usually stable. A Weber B fracture is stable when there is no medial injury — no medial tenderness, and the space between the talus and the medial malleolus is normal even on a stress radiograph. A Weber C fracture injures the syndesmosis and is unstable. The Maisonneuve fracture is a proximal fibular fracture with medial injury and syndesmotic disruption, so in an ankle injury with pain near the knee the whole leg must be imaged. A dislocated ankle with tented skin or a pale foot is reduced at once, even before radiographs, to save the skin and the circulation. In patients with diabetes and neuropathy complications are more frequent, and immobilisation lasts longer.
Key points
- Ottawa rules: X-ray for tenderness at the back edge of a malleolus, or when 4 steps cannot be taken.
- Weber: A below, B at, C above the syndesmosis.
- Stability depends on the medial side and the syndesmosis.
- Unstable — bimalleolar, Weber C, talar shift — surgery.
- Maisonneuve: proximal fibular fracture with syndesmotic injury.
Summary table
| Type | Level of fibular fracture | Stability | Treatment |
|---|---|---|---|
| Weber A | Below the syndesmosis | Usually stable | Boot or bandage and weight-bearing as tolerated |
| Isolated Weber B | At the syndesmosis, no medial injury | Stable if the medial space is normal on stress view | Boot, weight-bearing and radiographic follow-up |
| Weber B with medial injury | At the syndesmosis with medial fracture or ligament tear | Unstable | Open reduction and internal fixation (ORIF) |
| Weber C | Above the syndesmosis | Unstable, syndesmotic injury | Internal fixation and syndesmotic fixation |
| Maisonneuve | Proximal fibula with medial injury | Unstable | Syndesmotic fixation |
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Sources
- Rockwood and Green's Fractures in Adults, 9th ed. (2019) — Ankle Fractures
- Stiell IG et al., Ottawa Ankle Rules, JAMA (1993) — Decision rules for the use of radiography in acute ankle injuries
- NICE Guideline NG38, 2016 — Fractures (non-complex): assessment and management
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.