Ottawa Ankle Rules Calculator

Work out ottawa ankle rules instantly with clear inputs, formula shown and shareable results.

About Ottawa Ankle Rules Calculator

Applies the Ottawa ankle rules: with malleolar zone pain, imaging is needed if there is bone tenderness at a malleolar landmark or the patient cannot take four steps.

Formula

Ottawa ankle rules

Radiography indicated if malleolar zone pain plus either tenderness at the posterior edge or tip of either malleolus, or inability to bear weight for four steps

Worked example

With the default values below, Ottawa Ankle Rules Calculator returns Imaging recommendation of Ankle radiography indicated by the Ottawa rules. Change any input above and every figure here is recalculated in your browser.

Inputs used

Pain in the malleolar zoneone of Yes, No: Yes
Bone tenderness at a malleolar landmarkone of Posterior edge or tip of either malleolus, None: Posterior edge or tip of either malleolus
Able to take four stepsone of Yes, No: No

Results

Imaging recommendation: Ankle radiography indicated by the Ottawa rules
Positive criteria: 2
Applicability: Malleolar zone pain present, so the rule applies
Evidence note: The rule is close to 100% sensitive for clinically significant malleolar fracture

Step by step

1Values used
2Ottawa ankle rules
3Imaging recommendation= Ankle radiography indicated by the Ottawa rules
4Positive criteria= 2
5Applicability= Malleolar zone pain present, so the rule applies
6Evidence note= The rule is close to 100% sensitive for clinically significant malleolar fracture

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to whole numbers, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.
This is an estimate for general information and not professional medical advice. See the full disclaimer for the limits that apply to this kind of calculator.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.

Frequently Asked Questions

Do the rules apply to children?

They have been validated in children over about five years old, but local policy should be followed.

What about midfoot pain?

The separate Ottawa foot rules cover the navicular and base of the fifth metatarsal.