- Discussion:
    - anulus fibrosus makes up peripheral portion of disk structure;
    - composed of fibrocartilage and type I collagen;
    - fibers of anulus run obliquely between vertebrae and are arranged primarily in concentric layers;
          - direction of the fibers in successive layers alternates, w/ one layer crossing another at angles of 30-60 deg;
    - at periphery some annular fibers extend past cartilage edge plate to enter the bone of body as Sharpey's fibers;
           - deep fibers either insert into the cartilage at each end of disc or bend w/ nucleus pulposus;

- Innervation:
    - neural fibers are found in the outer rings of anulus;
    - nerve fibers are branches of the sinu vertebral nerve dorsally;
    - ventral branches arise from the sympathetic chain that courses anterolaterally over the vertebral bodies;

- Annular Tear:

- Disc Herniation:
    - anulus is wider anteriorly than posteriorly (i.e., Nucleus pulposus is situated eccentrically)

MRI and discography of annular tears and intervertebral disc degeneration. A prospective clinical comparison.

Healing potential of the anulus fibrosus.