Ottawa ankle rules

Decision rules for the use of radiography in acute ankle injuries. Refinement and prospective validation

Stiell IG, Greenberg GH, McKnight RD, et al. JAMA 1993 · PMID 8433468 · doi:10.1001/jama.269.9.1127

Question

Can a simple clinical decision rule safely identify which patients with acute ankle injuries need radiographs?

Design

Two-stage prospective study in two Canadian university hospital emergency departments: validation and refinement of the original rules, then validation of the refined rules.

Patients

Adults presenting with acute ankle injuries (convenience sample).

Intervention

Ottawa ankle rules (bony tenderness at specified sites and inability to weight-bear four steps)

Comparison

Radiographic diagnosis of fracture

Primary outcome

Sensitivity for clinically significant malleolar and midfoot fractures

Key result

The refined rules detected essentially all clinically significant malleolar and midfoot fractures in validation, while allowing a substantial reduction in radiography.

Limitations

Derived in adults in Canadian emergency departments; specificity is low, so many radiographs are still taken.

Impact on practice

The Ottawa ankle rules are the standard tool in UK emergency departments to decide whether ankle or foot radiographs are needed.