Which cervical ligament reinforces the posterior aspect of the annulus fibrosis of the lower cervical intervertebral discs?

• A. ALL
• B. Ligamentum flavum
• C. Nuchal ligament
• D. PLL

Answer: (D)

The posterior longitudinal ligament is the structure that reinforces the back part of the intervertebral disc. It runs along the posterior surfaces of the vertebral bodies inside the spinal canal, just in front of the spinal cord, and attaches to the discs themselves. Because it lies behind the vertebral bodies, it provides a continuous barrier against posterior bulging of the annulus fibrosus and helps stabilize the spine when bending forward. The anterior longitudinal ligament sits on the opposite side and reinforces the front of the disc, the ligamentum flavum connects adjacent laminae, and the nuchal ligament is a superficial neck structure — none of these specifically reinforce the posterior aspect of the annulus like the posterior longitudinal ligament.