Musculoskeletal

Ottawa Knee Rule

Five criteria for radiographs following acute knee trauma.

Intended population: Adults with acute blunt knee injury and a reliable examination.

All responses must reflect a clinician's verified history and examination. An unassessed finding is not an absent finding.
This rule addresses fractures, not ligament, meniscus, or tendon injuries. Urgent neurovascular assessment takes priority.

Age (years)

Acute blunt knee trauma within 7 days, reliable examination, not pregnant, no isolated skin injury, and not a return assessment?

Fibular head tenderness?

Isolated patellar bone tenderness (no other knee bone tenderness)?

Unable to flex the knee to 90°?

Unable to take 4 steps both immediately after injury and during evaluation?

Sources and scoring references

Original Ottawa Knee Rule derivation (1995) ↗NSW Health adult Ottawa knee rules ↗

Implementation references reviewed October 28, 2026. Verify applicability and unusual or treatment-changing results against the linked references and local guidance.