This is one of the most unusual causes of lateral knee pain. It affects the joint between the top of the shin bone (tibia) and the fibular, the small, thin bone that runs down the outer side of the shin, just below the knee joint on the outer side. It takes a large force to dislocate the joint, . a car accident, but it can also partially dislocate (sublux) usually due to a fall when the foot is plantarflexed (toes pointing down), which often also damages the tibiofibular ligament. Symptoms usually include lateral knee pain, instability especially during deep squats and sometimes an obvious deformity at the side of the knee. There may also be associated damage to the peroneal nerve leading to pins and needles or numbness around the outer knee.