Concurrent Validity of the Anterior Drawer Test and an Arthrometer in Evaluating Ankle Laxity

Abstract

This study focused on the concurrent validity and reliability of an ankle arthrometer and clinical tests of ankle laxity. A posttest-only control group design was used to compare anterior-posterior (AP) displacement in participants with clinically graded laxity (mechanical instability) and a control group. Forty-four individuals with no recent ankle sprains participated in this study. An ankle arthrometer measured AP displacement, and one investigator clinically graded the anterior drawer test. Pearson correlations were significant (r = 0.48, P < .05) between the anterior drawer and arthrometer measurements of AP displacement. Independent t tests revealed significantly greater AP displacement (P < .05) in mechanically unstable ankles on the anterior drawer test. The intraclass correlation coefficients [2,1) for arthrometer AP displacement ranged from 0.44 to 0.87, with reliability decreasing as the laxity grade increased. The ankle arthrometer is a reliable measure of AP laxity and has concurrent validity with a standardized clinical grading system in differentiating levels of joint laxity.