Cartilage

Cartilage is a stiff yet flexible material that is very good at resisting compression, cushioning the ends of a bone where it meets another bone at a joint. If you imagine a chicken drumstick, the cartilage is the white gristly material at the end of the bone.

Its hardness lies somewhere in between tendon and bone, giving the forces that pass through a joint a smooth transition between one bone and the next. Some joints exposed to extra large compressive forces, such as the knee joint, are have extra thick cartilage discs, called menisci.

Made up of a dense network of collagen that resists it tearing apart, cartilage provides excellent shock absorption and protection of the underlying bone. Natures added specialised solution for cartilage is to imbed in its collagen network a multitude of molecules of various sizes which are magnets to water. By binding to water they help make cartilage very effective at resisting compressive forces in a similar way as a water-filled bladder. Defective cartilage is known to be associated with painful arthritis.