Skeleton intervertebral discs. It is not as hard and rigid as bone but is stiffer and less flexible than muscle. Cartilage is composed of specialized cells called chondrocytes that produce a large amount of extracellular matrix composed of Type II collagen (except Fibrocartilage which also contains type I collagen) fibers, abundant ground substance rich in proteoglycan, and elastin fibers. Cartilage is classified in three types, elastic cartilage, hyaline cartilage and fibrocartilage, which differ in the relative amounts of these three main components. Unlike other connective tissues, cartilage does not contain blood vessels. The chondrocytes are supplied by diffusion, helped by the
Articular cartilage damage fill in articular cartilage defects, its structure is significantly different from that of hyaline cartilage; it is much denser and it doesn't withstand the demands of everyday activities as much as hyaline cartilage. It is therefore at a higher risk of breaking down. Wang "et al."(2006) found that small articular cartilage defects can progress to osteoarthritis over time if left untreated. An articular cartilage defect that initially may be small still has the potential to have a physical and chemical "domino effect" on the surrounding "normal" articular cartilage. Though articular cartilage damage is not life-threatening, it does strongly affect one's