Posterior longitudinal ligament

A crucial ligament that stabilizes the spine by running along the back of the vertebral bodies.

The posterior longitudinal ligament is a fibrous band that extends along the posterior aspect of the vertebral bodies from the base of the skull to the sacrum. It is narrower compared to its anterior counterpart and is attached to the intervertebral discs at intervals, providing support and strength to the spine. This ligament plays a significant role in the overall stability of the spinal column.

Terminologia Anatomica

ligamentum longitudinale posterius

System

Musculoskeletal system

Function

The primary function of the posterior longitudinal ligament is to provide mechanical support to the spine, specifically helping to resist excessive flexion (forward bending) of the vertebral column. It helps to maintain the alignment of the vertebrae and prevent them from shifting out of place. Additionally, by anchoring the intervertebral discs to the vertebral bodies, it contributes to the overall structural integrity of the spine. This ligament also plays a role in protecting the spinal cord and nerves by maintaining the proper spacing and alignment necessary for these structures to function without obstruction.

Location

The posterior longitudinal ligament is located within the vertebral canal of the spine, running along the posterior surface of the vertebral bodies from the upper cervical vertebrae to the sacral region. It lies directly in front of the spinal cord, encapsulating it along its length, and forms a continuous band that traverses the entire length of the spine. Its position allows it to effectively connect multiple vertebrae together and link them with the intervertebral discs.

Did You Know?

The posterior longitudinal ligament is often involved in degenerative spinal conditions, where it can thicken and lead to spinal stenosis or nerve compression.
In contrast to the more robust anterior longitudinal ligament, the posterior longitudinal ligament is thinner and less elastic, making it more vulnerable to injury during trauma.
This ligament is involved in important reflexes during spinal movements, aiding in proprioception, which helps the body sense its position in space.