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- Discussion:
    - cartilage end plate contains no fibrillar connection w/ collagen of subchondral bone of the vertebrae;
    - this lack of interconnection between end plate and the vertebrae may render disc biomechanically weak against horizontal shear forces;
    - outer 2/3 of annulus fibrous are firmly anchored into vertebral bodies;
    - intervertebral disc in the adult is avascular;
    - cells w/in it are sustained by diffusion of nutrients into disc thru porous central concavity of the vertebral end plate;
    - glycoaminoglycan turnover in the disc is quite slow, requiring 500 days