MSKOrthopaedics

Ottawa Ankle and Foot Rules

Clinical decision rule for ankle/foot X-ray after acute injury. >98% sensitive for clinically important fractures. Reduces unnecessary imaging by ~30%.

ANKLE: Tenderness at posterior edge or tip of LATERAL malleolus (distal 6 cm)?

ANKLE: Tenderness at posterior edge or tip of MEDIAL malleolus (distal 6 cm)?

ANKLE: Unable to bear weight immediately AND in ED (4+ steps)?

FOOT: Tenderness at the navicular bone?

FOOT: Tenderness at the base of the 5th metatarsal?

FOOT: Unable to bear weight (same criteria as above)?

Negative

Ottawa Rules Result

Ottawa Negative — Ankle and foot X-ray not required

No ankle criteria met. No foot criteria met. No criteria met. Safe to discharge without imaging if no other concerns. Note: Ottawa Rules apply only to acute ankle/foot injuries in adults. Exclude patients with isolated skin injuries, intoxication, pregnancy, distracting injuries, or diminished sensation.

Reference: Stiell IG et al. JAMA 1994

Medical Disclaimer: This calculator is a clinical decision support tool for qualified healthcare professionals. It does not replace clinical judgement. Always interpret results in the full clinical context. Reference: Stiell IG et al. JAMA 1994.

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