High Reproducibility of a Novel Fixed Anterior Drawer Test for Diagnosing Ankle Instability

Abstract

Category: Ankle Introduction/Purpose: The manual traditional anterior drawer test (ADT) is essential for the treatment decision of chronic ankle instability, but have been pointed out of comparatively low reproducibility and accuracy, especially in less experienced hands. To clarify the inter-examiner reproducibility, we compared the actual distance of anterior translation between the junior and senior examiner in the ADT. We also evaluate the diagnostic abilities of the traditional ADT and a novel modified ADT, fixed ADT. Methods: Thirty ankles were included in this study and the ankle instability was defined by the stress radiography. All subjects were performed two methods of manual ADT by junior and senior examiner, and judged the ankle instability in a blinded fashion. The anterior drawer distance was calculated from the lengthening measured by the capacitance-type sensor device. Results: The amount of anterior translation of junior examiner was significantly lower than senior examiner in the traditional ADT (3.3 vs. 4.5 mm, p=0.016), while, there was no significant difference between two examiners in the fixed ADT (4.6 vs. 4.1 mm, p=0.168). The inter-examiner reliability of fixed ADT was higher than traditional ADT. In the junior examiner, the diagnostic accuracy of the fixed ADT was higher than that of traditional ADT (sensitivity, 0.40 vs. 0.80; specificity, 0.75 vs. 0.80, respectively). Conclusion: Fixed ADT may have advantage for a simple manual test of ankle instability as a method with less error between examiners.