| A knee X-ray is only required for knee injury patients with 1 or more of these |
☐Age > or equivalent to 55 years ☐Isolated tenderness of the patella (no bone tenderness of the knee
other than the patella) ☐Tenderness at the head of the fibula ☐Unable to flex to 90 degrees ☐Unable to weight bear both immediately and in the emergency department
for 4 steps (4 steps = Able to transfer weight twice onto each lower
limb regardless of limping) |
The Ottawa Knee Rules are guidelines that were developed, in Canada, to aid Emergency Physicians in deciding when to use radiography for patients with injuries to the knee.
These rules have been clinically tested and appear to lead to a decrease in the use of knee radiography, waiting times, and costs without patient dissatisfaction or missed fractures.
Fractures occur in only 6% of knee trauma. The Ottawa Knee Rules have 97% sensitivity and 27% specificity and reduce knee X-rays by 28%. The Pittsburgh Knee Rules have 99% sensitivity, 60% specificity and reduce knee X-rays by 52%.
A knee X-ray is only required for knee injury patients with 1 or more of these:
References:
Bulloch B, et al. Validation of the Ottawa Knee Rule in children: a multicenter study. Ann Emerg Med. Jul2003;42(1):48-55.
Stiell IG, et al. Prospective validation of a decision rule for the use of radiography in acute knee injuries.JAMA. Feb 1996;275(8):611-615.
Stiell IG, et al. Use of radiography in acute knee injuries: need for clinical decision rules. Acad EmergMed Nov 1995;2(11):966-73.
Stiell IG, et al. Implementation of the Ottawa Knee Rule for the use of radiography in acute knee injuries.
Tandeter HB, et al. Acute knee injuries: use of decision rules for selective radiograph ordering. Am FamPhysician. Dec 1999;60(9):2599-2608.