Ottawa knee rules

Criteria:

X-ray is only required in patients who have an acute injury with one or more of the following:

1. Age >55
2. Isolated tenderness of the patella (no other bony tenderness).
3. Tenderness at the fibular head.
4. Inability flex to 90 degrees
5. Inability to walk 4 steps BOTH immediately after the injury and in the ED

Caveats

1. 99% sensitive in children over age 5.
2. Beware of the Tillaux Fracture in adolescents with anteromedial ankle pain, as they would not qualify for imaging according to this rule.

External Links

MDCalc - Ottawa Knee Rules

See Also

• Knee (Main)
• Ottawa Ankle Rules

Sources

1. Bachmann LM, Haberzeth S, Steurer J, et al. The accuracy of the Ottawa knee rule to rule out knee fractures: a systematic review. Ann Intern Med. 2004 Jan 20;140(2):121-4.
2. Bulloch B, Neto G, Plint A, et al. Validation of the Ottawa Knee Rule in children: a multicenter study. Ann Emerg Med. 2003 Jul;42(1):48-55.
3. Stiell IG, Greenberg GH, Wells GA, et al. Derivation of a decision rule for the use of radiography in acute knee injuries. Ann Emerg Med. 1995 Oct;26(4):405-13.
4. Stiell IG, Greenberg GH, Wells GA, et al. Prospective validation of a decision rule for the use of radiography in acute knee injuries. JAMA. 1996 Feb 28;275(8):611-5.
5. Stiell IG, Wells GA, Hoag RH, et al. Implementation of the Ottawa Knee Rule for the use of radiography in acute knee injuries. JAMA. 1997 Dec 17;278(23):2075-9.
6. Vijayasankar D, Boyle AA, Atkinson P. Can the Ottawa knee rule be applied to children? A systematic review and meta-analysis of observational studies. Emerg Med J. 2009 Apr;26(4):250-3.