Of all the nerves exiting the sacral plexus including the Posterior Femoral Cutaneous, Sciatic, Saphenous, Deep Peroneal Nerve, Superficial Peroneal Nerve, and Tibial Nerve, the Deep Peroneal Nerve as a branch of the Sciatic Nerve is the only nerve that innervates the lateral knee (listed in the image above as Common Fibular Nerve) and top of the foot and traverses the posterior lateral knee behind the fibula.  

Question: How could this patient cause injury to the Deep Peroneal Nerve behind the right lateral knee from her fall on the left side of her body?