Comprehensive Osteopathic Medical Licensing Examination (COMLEX USA) Practice

What distinguishes the posterior longitudinal ligament from the anterior longitudinal ligament?

1. It is wider

2. It is thinner

3. It covers more area

4. It is flexible

The correct answer is: It is thinner

The posterior longitudinal ligament is distinct from the anterior longitudinal ligament primarily in its thickness. The posterior longitudinal ligament is typically thinner compared to the anterior longitudinal ligament. This anatomical feature is significant as it plays a role in the structural integrity and function of the spine. The anterior longitudinal ligament, which is broader and thicker, extends along the anterior aspect of the vertebral bodies, providing stability and preventing hyperextension of the spine. In contrast, the thinner posterior longitudinal ligament runs along the posterior aspect of the vertebral bodies and is crucial in resisting hyperflexion and providing some support against disc herniation, particularly in the cervical region. Understanding the anatomical differences, including thickness, can aid in comprehending the ligamentous support system of the spine and their respective roles in spinal mechanics and injury prevention.