Introduction of the Low Risk Ankle Rule to A Paediatric Emergency Department

SLR - July 2020 - Lewis A. Kane

Reference: Tormey P, Callender O, Fitzpatrick P, Okafor I, McNamara R, Kandamany N. Introduction of the Low Risk Ankle Rule to A Paediatric Emergency Department. Injury. 2020 March 1;51(3):633–5

Scientific Literature Review

Reviewed By: Lewis A. Kane, DPM, MS
Residency Program: Kaiser SF Bay Area Foot & Ankle – Oakland, CA

Podiatric Relevance: Acute ankle injury is a common presenting complaint of many pediatric patients, especially within the emergency department setting. Appropriate clinical evaluation of these patients is critical to avoid missing a significant injury and for implementing the appropriate rehabilitation course. In addition, among this population of patients, it is especially important to follow ALARA principles to reduce the risk of lifetime radiation exposure. This article presents one hospital’s implementation of a triage exam—the Low Risk Ankle Rule—and its influence on injury diagnosis.

Methods: The Low Risk Ankle Rule was introduced to a busy pediatric emergency department in the summer of 2017. The rule asserts that tenderness and edema isolated to the distal fibula and/or lateral collateral ligaments is low-risk for significant injury among the pediatric population and does not warrant X-ray evaluation. The authors compared clinical charts after the implementation period to an audit group from 2016 to determine changes in rate of radiography and incidence of missed significant injuries. 

Results: The rate of ordered X-rays in pediatric patients presenting with acute ankle injury fell from 90.7 percent to 43.4 percent after introduction of the new triage system. Eleven of 30 patients with high-risk exams were found to have acute fractures. Four of 49 patients with low-risk exams ultimately had X-rays due to parental anxiety or representation; none were noted to have fractures.

Conclusions: The authors note that the rate of X-ray among this patient group fell by 47.3 percent after implementation of the Low Risk Ankle Rule. This is a clinically significant reduction in radiation among pediatric patients, and no fractures were missed during the study period. While it is commendable to prevent unnecessary radiation, the study was not designed to detect missed injuries. Data was collected over the course of two months, and it is plausible that longer follow up may identify children with persisting pain and/or limitations due to overlooked injuries. Nonetheless, following this triage system can significantly reduce the rate of unnecessary radiation in the pediatric patient population.