Thickest in cervical and lumbar region, where movement is greatest
Act as shock absorbers
Loses resilience with advancing age
Consists of 2 parts: peripheral annulus fibrosus and central nucleus pulposus
Annulus fibrosus: fibrocartilage, collagen fibres arranged in concentric layers or sheets. Peripheral fibers strongly attached to anterior and posterior longitudinal ligaments
Nucleus pulposus: ovoid mass of gelatinous material contains large amount of water, small collage fibre content. Situated closer to posterior margin of disc
