Espiral AtlasCruciate ligament of the atlas (transverse ligament and longitudinal bands)
ligamentum cruciforme atlantis
Study entry
Classification
Ligament of the median atlantoaxial joint.
Surfaces
The transverse ligament runs from one lateral mass of the atlas to the other and passes between the dens of the axis and the spinal cord. The longitudinal fascicles, vertical and much weaker, rise from the transverse ligament to the occipital bone and descend to the body of C2.
Capsule
Together with the anterior arch of the atlas, the transverse ligament forms the "tunnel" that embraces the dens of the axis.
Movements
It holds the dens against the anterior arch: it stops the dens from moving backward and the atlas from moving forward, which would compress the cord in the vertebral foramen of C1.
Blood supply
Spinal branches of the segmental arteries of the level, which supply the bones, the periosteum, the ligaments and the meninges around the epidural space: 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; in the pelvis, from the iliolumbar and the lateral and median sacral 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
Rupture of the transverse ligament leaves the dens free to move backward and can compress the upper cervical spinal cord. [CHECK: only the title of the clinical box was read]
Source: cap. 2, «Articulaciones craneovertebrales» e «Atlas»; fig. 2-20 A; «Vascularización de la columna vertebral» e «Nervios de la columna vertebral»