Prospective validation and head-to-head comparison of 3 ankle rules in a pediatric population.
OBJECTIVE
The Ottawa Ankle Rules, Low-Risk Exam, and Malleolar Zone Algorithm are assessment rules designed to minimize radiographs performed on children with ankle trauma. We aim to determine the criterion validity of the abovementioned 3 rules for predicting clinically important ankle fractures in children.


METHODS
This was a prospective cohort study performed in a pediatric emergency department. Children aged 16 years and younger and with acute ankle trauma were eligible. Physicians were initially trained to assess patients according to the Ottawa Ankle Rules, Low-Risk Exam, and Malleolar Zone Algorithm. Furthermore, they implemented each rule with a standardized diagram. Radiography and referral to orthopedics were left to the physicians' discretion. The primary outcome was the confirmation of a clinically important fracture confirmed during the orthopedic follow-up. Patients who did not require orthopedic follow-up were contacted by telephone.


RESULTS
Radiography was performed for 245 of the 272 participants. All patients with no radiograph were reached by telephone. Forty-seven participants had a clinically important fracture. The sensitivity and specificity of the rules were 1.00 (95% confidence interval [CI] 0.93 to 1.00) and 0.27 (95% CI 0.21 to 0.33) for the Ottawa Ankle Rules, 0.87 (95% CI 0.75 to 0.94) and 0.54 (95% CI 0.47 to 0.60) for the Low-Risk Exam, and 0.94 (95% CI 0.83 to 0.98) and 0.24 (95% CI 0.19 to 0.31) for the Malleolar Zone Algorithm.


CONCLUSIONS
The Ottawa Ankle Rules identified all children with a clinically important fracture, whereas the Low-Risk Exam and the Malleolar Zone Algorithm showed lower sensitivities. The Low-Risk Exam showed the best specificity for clinically important fractures, decreasing the need for radiograph by 49%, but had missed 6 important fractures.
Gravel
Jocelyn
J
Division of Emergency Medicine, Department of Pediatrics, CHU Sainte-Justine, Université de Montréal, Montréal, Quebec, Canada. graveljocelyn@hotmail.com
Hedrei
Philip
P
Grimard
Guy
G
Gouin
Serge
S
D000293:Adolescent; D000465:Algorithms; D016512:Ankle Injuries / Q000000981:diagnostic imaging*; D002648:Child; D002675:Child, Preschool; D019091:Critical Pathways; D003661:Decision Support Techniques; D004636:Emergency Service, Hospital; D005260:Female; D050723:Fractures, Bone / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011859:Radiography; D012680:Sensitivity and Specificity; D014193:Trauma Centers