The joints in the knees are amazingly assembled. With a ball and rotator that leads to one way bending it performs with amazing strength that can be further strengthen with proper exercise. Allowing the leg to bend in the middle propels the foot back and forth to allow movement. Also supports the body’s weight during the process while still in motion. When there is an area of break down or damage the effects can be huge. Many nerves and alerts are trigger to inform the mind of a problem. The additional sensitivity is for the body’s protection but can seeminly increase the “pain” we feel when damage occurs to the knee.