Try this mulligan technique:
http://www.mobilitywod.com/2012/12/knee-pain-got-full-knee-powerrange-of-motionpotential-terminal-knee-extension-part-3/

Also, make sure that you’re engaging the muscles in the foot properly – this can impact the alignment between the tibia and the femur, which in essence can create internal rotation of the femur (or external rotation of the tibia – they’re both essentially the same thing).

Hit up that popliteus with some love and focus on not only ankle ROM but muscular engagement when moving through the ankle ROM.