Where does the PLL extend?

Where does the PLL extend?

• A. T1 to L2
• B. Occiput to L5
• C. C1 to C7
• D. C2 to the sacrum

Answer: (D)

The posterior longitudinal ligament lies along the inside of the spinal canal, hugging the back of the vertebral bodies and intervertebral discs to help stabilize the column and limit extension. It begins at the body of the axis (the second cervical vertebra) and continues downward through the cervical, thoracic, and lumbar regions all the way to the sacrum, where it blends with the periosteum. Superiorly, above C2, its extension forms the tectorial membrane that attaches to the base of the skull, but the ligament proper ends at C2. So the length runs from C2 to the sacrum.

The posterior longitudinal ligament lies along the inside of the spinal canal, hugging the back of the vertebral bodies and intervertebral discs to help stabilize the column and limit extension. It begins at the body of the axis (the second cervical vertebra) and continues downward through the cervical, thoracic, and lumbar regions all the way to the sacrum, where it blends with the periosteum. Superiorly, above C2, its extension forms the tectorial membrane that attaches to the base of the skull, but the ligament proper ends at C2. So the length runs from C2 to the sacrum.