A soft central part of an intervertebral disc which disappears in old age.
Center of the intervertebral disc.
The center cushioning gelatinous mass lying within an intervertebral disk; the remnant of the notochord.
Located at the center of each vertebral disk, there exists an elastic and spongy mass commonly known as the nucleus pulposus.
The partially liquid central region within an intervertebral spinal disc. According to one theory concerning spinal disc pain, this structure can protrude to the side and exert pressure on a spinal nerve, resulting in pain.