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
Meniscus (anatomy) degenerative knee disease. The term meniscus derives from Greek μηνίσκος "meniskos", "crescent moon". The word was also used for curved things in general, such as a necklace or a line of battle. Meniscus (anatomy) A meniscus is a crescent-shaped fibrocartilaginous anatomical structure that, in contrast to an articular disk, only partly divides a joint cavity. In humans they are present in the knee, wrist, acromioclavicular, sternoclavicular, and temporomandibular joints; in other animals they may be present in other joints. Generally, the term 'meniscus' is used to refer to the cartilage of the knee, either to the lateral or medial meniscus.