Your knee is the largest joint in your body and one of the most complex. The bones, cartilage, ligaments, and muscles work in harmony to produce movement. Articular cartilage is at the ends of the femur and tibia, and the back of the patella. Meniscal cartilage acts as "shock absorbers" between your femur and tibia. Different from articular cartilage, the meniscus is tough and rubbery to help cushion and stabilize the joint. The knee bones are connected to each other by ligaments. The four main ligaments in your knee act like strong ropes to hold the bones together and keep your knee stable.