Accuracy of Anterolateral Drawer Test in Lateral Ankle Instability: A Cadaveric Study

Abstract

Background: In the assessment of lateral ankle instability, the anterior drawer test has been found to be inaccurate and the focus on pure anterior translation cannot properly perceive the anterolateral rotatory nature of the talar displacement. In order to address this, the anterolateral drawer test can be done with digital palpation of the talar displacement anterolaterally with a controlled angle of plantarflexion as well as application of the translational force. Materials and Methods: We evaluated the anterolateral drawer test and the original anterior drawer test in 10 fresh below-the-knee specimens using a direct anatomic measurement (DAM) loaded by a Telos stress device as a reference. Specimens were assigned into three groups: intact ligaments, ATFL-cut, and ATFL&CFL-cut. The examiners were blinded with one performing the anterolateral drawer test (E1) while the other performed the original anterior drawer test (E2). Results: Pearson's correlation coefficient indicated a statistically significant linear relationship between DAM/E1 r = 0.931, p < 0.001 but not between DAM/E2 r = 0.519, p = 0.124. Intraclass correlation coefficient show correlation between DAM/E1 and DAM/E2 to be 0.945 ( p < 0.001) and 0.683 ( p = 0.051). When 3 mm or more was used as the threshold to diagnose a lateral ligament rupture, sensitivity and specificity were E1(100%, 100%) and E2(75%, 50%). Conclusion: The anterolateral drawer test showed high accuracy in the determination of lateral ankle instability and in the diagnosis of a ligament rupture. Clinical Relevance: Further investigation regarding the accuracy and reliability of this test in comparison with the original anterior drawer test is warranted in a patient population with ankle instability.