ObjectivesAnkle and midfoot injuries constitute one of the most frequent reasons to visit the pediatric emergency department (ED). The aims of the study were (1) to determine the feasibility of the Ottawa Ankle Rules (OARs) in a pediatric ED and its reliability to safely manage ankle and midfoot injuries and (2) to verify the impact in reducing the number of radiographs, healthcare costs, and time spent in the ED.MethodsThe prospective study enrolled 90 patients for the control group and 94 for the case group. For the control group, the standard of practice was registered. In the case group, before beginning enrolment, an instruction of how to apply the OARs were given to all clinicians. After that, OARs were applied according to patient complaints. A follow-up call was made for both groups.ResultsThe mean age of the control group was 11.9 years (standard deviation, 3.267 years), whereas in the case group was 11.3 years (standard deviation, 3.533 years). Demographic and injury characteristics were similar in both groups. A significant statistical difference was verified in the number of radiographs (P = 0.001) with a reduction of 16.7% in the case group. Patients who did not perform radiography, in the case group, spent at least 1 hour less than the ones who did. The OARs have shown a sensitivity of 100% (95% confidence interval, 39.76–100.00) and specificity of 23.33% (95% CI, 15.06–33.43) with a negative predictive value of 100%.ConclusionsThe OARs are an important clinical instrument with a high sensitivity and negative predictive value, which allows clinicians to avoid unnecessary exposure to radiation without missing clinically relevant fractures.