Figure 1. Negative Lelli test or lever sign of the left knee, with positivity of the right knee. In this test the examiner applies downward force immediately proximal to the knee joint, with the other fist beneath the proximal third of the calf muscle. With the intact anterior cruciate ligament (ACL), the heel should rise from the table (negative test). In the case of ACL rupture, the heel of the patient remains on the table, since the femur displaces posteriorly (positive test).