Posterior Drawer Test

This animation demonstrates the posterior drawer test. In the one image you can see that when the tibia is pushed backwards, it falls behind the femoral condyle. In the other photo the tibia is pulled forward to it's normal position, and is highlighted by the light.
When the tibia is forward it is referred to as the tibia step. This test is graded from 1-3.
Grade 1  0 -5 mm
Grade 2  6 -10 mm (the tibia is equal to the femoral condyle)
Grade 3  > 10 mm (the tibia is behind the condyle)