The tectorial membrane is derived from which ligament?

The tectorial membrane is derived from which ligament?

• A. Tectorial membrane
• B. Posterior longitudinal ligament (PLL)
• C. Interspinous ligament
• D. Ligamentum flavum

Answer: (B)

The tectorial membrane is the superior continuation of the posterior longitudinal ligament. As the PLL ascends beyond the axis to the cranial end of the spinal canal, it broadens and blends with the dura to form this membrane, which attaches to the occipital bone at the basisphenoid region and covers the odontoid area. This extension helps stabilize the craniovertebral junction and limits excessive flexion of the head on the neck. The other ligaments mentioned do not form this superior extension: interspinous ligaments connect spinous processes, ligamentum flavum connects adjacent laminae, and naming the tectorial membrane itself as its own origin isn’t applicable.

The tectorial membrane is the superior continuation of the posterior longitudinal ligament. As the PLL ascends beyond the axis to the cranial end of the spinal canal, it broadens and blends with the dura to form this membrane, which attaches to the occipital bone at the basisphenoid region and covers the odontoid area. This extension helps stabilize the craniovertebral junction and limits excessive flexion of the head on the neck. The other ligaments mentioned do not form this superior extension: interspinous ligaments connect spinous processes, ligamentum flavum connects adjacent laminae, and naming the tectorial membrane itself as its own origin isn’t applicable.