Anterior Talocrural Joint Laxity: Diagnostic Accuracy of the Anterior Drawer Test of the Ankle.

This prospective, blinded, diagnostic accuracy study with the aim of investigating the diagnostic accuracy of the ankle anterior drawer test (ADT) to detect anterior talocrural joint laxity in adults with a history of lateral ankle sprain. The ADT is used to manually detect anterior talocrural joint laxity following lateral ankle sprain injury; although, the diagnostic accuracy of this test has not been established. Sixty-six individuals with a history of lateral ankle sprain were examined with the ADT. Anterior talocrural joint laxity was measured digitally from ultrasound images of the talofibular interval during performance of the ADT. Anterior talocrural joint laxity was measured digitally in 20 control subjects to establish a reference standard as well. The authors defined ADT results as “positive” or “negative” based on this and a second reference standard established from the literature. The group with a history of lateral ankle sprain had 3.36 (3.25) mm mean (SD) anterior talocrural joint laxity compared with 0.17 (1.87) mm in the control group. Thirty-five of 66 (53%) subjects demonstrated ≥ 2.3 mm of anterior laxity and 24 (36%) at a reference standard of ≥ 3.7 mm of anterior talocrural joint laxity. Sensitivity (95% CI) of the ADT was 0.74 (0.58, 0.86) and 0.83 (0.64, 0.93) at the ≥ 2.3 mm and ≥ 3.7 mm reference standards, respectively. Specificity (95% CI) of the test was 0.38 (0.24, 0.56) and 0.40 (0.27, 0.56), respectively. Positive likelihood ratios were 1.2 and 1.4 while the negative likelihood ratios were 0.66 and 0.41, respectively.

The ADT has some limitations in the detection of excessive anterior talocrural joint laxity, however, it may provide useful information when used in side-to-side ankle comparisons and in addition to other physical exam procedures like palpation.