The yellow ligaments (ligamenta flava) in the neck region are thin and broad ligaments that extend between the laminae of adjacent vertebrae on both sides of the spine and are associated with the vertebral canal.
Each yellow ligament (ligamentum flavum) passes from the superior surface of the lamina of the vertebra below to the inferior surface of the lamina of the vertebra above.
In the neck region, these ligaments are present from C1, C2 to C7 vertebrae, but overall from C1, C2 to S1 vertebrae. In the superior direction, yellow ligaments continue as atlantoaxial and atlantooccipital membranes.
These ligaments are called yellow because they actually appear yellowish as they contain a high amount of elastin but less collagen. Elastin gives the yellow appearance and gives them flexibility.
These ligaments resist the separation of the vertebral laminae during flexion of the spine and limits hyperflexion. They also aid in extending the spine back to the anatomical position. Besides mentioned functions, yellow ligaments also enclose the posterior part of the vertebral canal.