BACKGROUND: A recent multicenter prospective Canadian study presented 
prospective evidence supporting the Low Risk Ankle Rules (LRAR) as a means of 
reducing the number of ankle radiographs ordered for children presenting with an 
ankle injury while maintaining nearly 100% sensitivity. This is in contrast to a 
previous prospective study which showed that this rule yielded only 87% 
sensitivity.
OBJECTIVE: It is important to further investigate the LRAR and compare them with 
the already validated Ottawa Ankle Rules (OAR) to potentially curb healthcare 
costs and decrease unnecessary radiation exposure without compromising 
diagnostic accuracy.
METHODS: We conducted a retrospective chart review of 980 qualifying patients 
ages 12months to 18years presenting with ankle injury to a commonly staffed 310 
bed children's hospital and auxiliary site pediatric emergency department.
RESULTS: There were 28 high-risk fractures identified. The Ottawa Ankle Rules 
had a sensitivity of 100% (95% CI 87.7-100), specificity of 33.1% (95% CI 
30.1-36.2), and would have reduced the number of ankle radiographs ordered by 
32.1%. The Low Risk Ankle Rules had a sensitivity of 85.7% (95% CI 85.7-96), 
specificity of 64.9% (95% CI 61.8-68), and would have reduced the number of 
ankle radiographs ordered by 63.1%. The latter rule missed 4 high-risk 
fractures.
CONCLUSION: The Low Risk Ankle Rules may not be sensitive enough for use in 
Pediatric Emergency Departments, while the Ottawa Ankle Rules again demonstrated 
100% sensitivity. Further research on ways to implement the Ottawa Ankle Rules 
and maximize its ability to decrease wait times, healthcare costs, and improve 
patient satisfaction are needed.