Ottawa Ankle

Determine need for ankle or foot X-ray after acute injury

Indication

id: malleolar_pain; label: Pain in the malleolar zone (ankle); type: yesno
id: lat_malleolus; label: Bone tenderness at posterior edge or tip of lateral malleolus; type: yesno
id: med_malleolus; label: Bone tenderness at posterior edge or tip of medial malleolus; type: yesno
id: ankle_weight; label: Unable to weight bear 4 steps immediately and in ED; type: yesno
id: midfoot_pain; label: Pain in the midfoot zone; type: yesno
id: met5; label: Bone tenderness at base of 5th metatarsal; type: yesno
id: navicular; label: Bone tenderness over navicular; type: yesno
id: foot_weight; label: Unable to weight bear 4 steps immediately and in ED; type: yesno

function(score, answers) { var ankleNeeded = false; var footNeeded = false; if (answers) { if (answers.malleolar_pain === 1 && (answers.lat_malleolus === 1 || answers.med_malleolus === 1 || answers.ankle_weight === 1)) { ankleNeeded = true; } if (answers.midfoot_pain === 1 && (answers.met5 === 1 || answers.navicular === 1 || answers.foot_weight === 1)) { footNeeded = true; } } if (ankleNeeded && footNeeded) return { risk: 'Positive', tier: 'Ankle + Foot X-ray Indicated', action: 'Obtain ankle AND foot radiographic series.', color: 'red' }; if (ankleNeeded) return { risk: 'Positive', tier: 'Ankle X-ray Indicated', action: 'Obtain ankle radiographic series.', color: 'red' }; if (footNeeded) return { risk: 'Positive', tier: 'Foot X-ray Indicated', action: 'Obtain foot radiographic series.', color: 'red' }; return { risk: 'Negative', tier: 'No X-ray Required', action: 'Imaging not indicated. Sensitivity 98–100% for clinically significant fractures.', color: 'green' }; }

Sensitivity 98–100% for clinically significant fractures — very safe to rule out
Specificity ~40% — many patients with positive Ottawa will have no fracture
Apply the ankle rule and foot rule separately — they test different zones
"Weight bear 4 steps" means ANY 4 steps, even limping

Stiell et al., JAMA 1993, 1994; Bachmann et al., BMJ 2003. Last reviewed: 2024-10-01