Inner annulus fibrosus in non-degenerated intervertebral disc shows bright signal on T2 weighted MR image

The intervertebral disc is a fibrocartilaginous joint that supports spinal forces while facilitating compound movements. To meet these demands, the disc has a complex structural organization that imparts unique physical properties. The nucleus pulposus matrix is composed mainly of high molecular-weight glycosaminoglycans (GAGs) with fixed negative charges that induce osmotic swelling (1). The annulus fibrosus limits the swelling of the nucleus pulposus and the motions between adjacent vertebrae.