Remember to check the Pre-ROM to see if there was an issue with symmetry for terminal knee extension as this may create the inability to set up an apples-to-apples comparison between the two legs.

The key here is to set each patella so that it is parallel to the table (facing directly forward). This is the zero degree starting point. You can hold the leg up off the table passively a bit and perform the motion as a spinning action or you can leave the leg on the table and perform the motion as a barrel roll type motion. Note which way it was performed. Ensure that there is no pelvis/spinal motion during the motion of the leg. Note the total displacement from the zero degree point in degrees.