Espiral AtlasLigamenta flava
ligamenta flava
Study entry
Classification
Ligaments of the joints between the vertebral arches.
Surfaces
They join the laminae of neighboring vertebrae: they run almost vertically from the lamina above to the lamina below, and the two sides meet at the midline.
Capsule
Wide bands of pale yellow elastic tissue. They form stretches of the posterior wall of the vertebral canal, alternating with the laminae. They are long, thin and wide in the neck, thicker in the thorax and thicker still in the lumbar region. Over the craniovertebral region they continue upward into the posterior atlanto-occipital and atlantoaxial membranes.
Movements
They resist separation of the laminae and limit sudden flexion, sparing the discs; they help maintain the normal curvatures. [CHECK: the OCR cuts off the next sentence, which talks about straightening the spine after flexion]
Blood supply
Posterior branches of the segmental arteries of the level, which supply the structures of the vertebral arch and the muscles of the back: in the neck, from the vertebral and ascending cervical arteries; in the thorax, from the posterior intercostals; in the abdomen, from the subcostal and lumbar arteries.
Innervation
Meningeal (recurrent) branches of the spinal nerves. They arise just after the nerve forms, return through the intervertebral foramen and supply the periosteum, the ligaments (especially the anterior longitudinal), the meninges and the annuli fibrosi of the discs. They carry pain from these structures.
Clinical
Hypertrophy of the ligamenta flava and of the articular processes narrows the vertebral canal (lumbar spinal stenosis).
Source: cap. 2, «Articulaciones de los arcos vertebrales» e cuadro clínico de estenose vertebral; «Vascularización de la columna vertebral» e «Nervios de la columna vertebral»