Anterior Drawer Test for Acute Anterior Talofibular Ligament Injuries of the Ankle: How Much Load Should be Applied during the Test?

Background: There is a lack of consensus regarding the magnitude of load for performing the anterior drawer test in evaluating acute ankle injuries. Purpose: To determine how much load should be applied during the anterior drawer test to detect the integrity of the anterior talofibular ligament. Methods: First, the anterior-posterior load-displacement response of nine cadaveric ankles was measured. Second, anterior displacement of the ankle was measured at 30 and 60 N of anterior load in 14 patients with acute tears of the anterior talofibular ligament. Results: In the cadaver study, the increased displacement by sectioning of the ligament measured at 10, 20, 30, and 40 N of anterior load were significantly greater than those measured at 60 N. In vivo examination of the subjects without anesthesia demonstrated that the injured-to-normal displacement value at 30 N of anterior load was significantly greater than the value at 60 N. Conclusions: This study suggests that a large magnitude of anterior load is not necessary to detect the integrity of the ligament during the anterior drawer test. Clinical Relevance: When evaluating the integrity of the anterior talofibular ligament in cases of acute ankle ligament injury, a relatively low-magnitude load should be applied.