Medical calculators
Ottawa Knee
Need for X-ray
For education. Check every result.
Anatium is a study resource, not medical advice. Nothing here is a diagnosis, a prescription or a substitute for a clinician who has seen the patient. Check every number against a current local protocol before it touches anyone, and never act on a result you cannot reproduce yourself.
How it is calculated
Ottawa knee rule: age 55 or over, isolated patellar tenderness, fibular head tenderness, inability to flex to 90 degrees, or inability to bear weight for four steps both immediately and in the department. any one means x-ray.
About
Whether a knee injury needs an X-ray. These rules exist to reduce radiography, not to increase it.
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