They help to preserve upright posture, preventing hyperflexion, and ensuring that the vertebral column straightens after flexion.

[citation needed] Each ligament consists of two lateral portions which commence one on either side of the roots of the articular processes, and extend backward to the point where the laminae meet to form the spinous process; the posterior margins of the two portions are in contact and to a certain extent united, slight intervals being left for the passage of small vessels.

[citation needed] Small veins that form anastomotic connections between the internal and external vertebral venous plexuses may pass between a pair of the ligaments.

[1] The marked elasticity of the ligamenta flava serves to preserve upright posture, and to assist the vertebral column in resuming it after flexion.

Because these ligaments lie in the posterior part of the vertebral canal, their hypertrophy can cause spinal stenosis, particularly in patients with diffuse idiopathic skeletal hyperostosis.

[7] This makes the ligamentum flavum an important landmark to overcome to ensure proper needle placement.