Intertester reliability of the Modified Anterior Drawer (Lachman) Test for anterior cruciate ligament laxity

Eight therapists each examined 16 subjects (14 with documented ACL pathology, two normal subjects) in a single session. Instrumented anterior laxity measurements were performed bilaterally on all subjects prior to testing. Therapists assessed the degree of anterior tibial translation on a visual analogue scale, and indicated whether the nominated knee tested positive or negative using the Lachman test. Intertester reliability in assessing anterior translation was low. Correlation between the overall therapists' translation measurements and the arthrometer was moderate. Intertester reliability in indicating whether the nominated knee tested positive or negative was low. These findings suggest that greater expertise is necessary for therapists to reliably use the Lachman test as an assessment procedure in evaluation of the injured knee.