Ottawa ankle and foot rules in China: applicability in a defensive environment

Abstract

Background: The introduction of any new diagnostic method in a specific clinical setting and culture requires considerable caution, as sensitivity and specificity may be significantly affected. Whether the Ottawa ankle and foot rules (OAFR) are feasible in the Chinese environment is controversial. This study gauges attitudes and calculates the sensitivity and specificity of OAFR in mainland China.

Methods: Short surveys were designed and disseminated to explore the perspective of emergency department trauma doctors and non-medical personnel towards OAFR. We conducted a prospective study at three hospital sites (one-level two hospital and two-level three hospitals) in three provinces. Documentation of OAFR outcomes was recorded in all patients with acute ankle and mid-foot injuries who presented to the three hospitals if they met the inclusion criteria. Anteroposterior and lateral radiographs of the ankle and/or foot were obtained for all patients based on the site of injury. All images were subsequently reviewed by a well-trained radiologist who was blinded to both the OAFR documentation and the emergency physician's interpretation. Radiographic results were compared with fracture prediction based on OAFR to calculate sensitivity and specificity in our patient population. Positive and negative predictive values were also calculated.

Results: Only 31.5% of trauma doctors claimed to have heard of OAFR before, and 19.5% of them knew them in detail. 69.5% considered that department leadership in support of a strict interpretation of the rules would assist in their implementation. Both doctors and patients cited potential missed fractures as the dominant concern regarding the application of OAFR. 88.0% of non-medical persons claimed that they could accept the doctor's opinion if made based on these rules. Those with higher educational attainment would be more likely to accept the doctor's opinion. Overall sensitivity was 98.4% and specificity was 26.3%, for detecting fractures in acute ankle and mid-foot injuries. Four fractures out of 602 patients were missed based on OAFR, with one displaced 2nd and 3rd metatarsal fracture resulting in surgery.

Conclusions: OAFR sensitivity in China is as high as in non-Asian populations. Their use is feasible and could be promoted to limit the unnecessary consumption of scare health resources. Survey data suggests implementation could be accepted by most doctors and patients, but would be hampered by the currently fragile doctor-patient relationship.

Keywords: China; Defensive medicine; Ottawa ankle and foot rules; Sensitivity; Specificity.