Connections of the vertebrae

The bodies of adjacent vertebrae are connected by means of intervertebral disks (disci intervertebrales), or intervertebral symphysis (symphysis intervertebrales), and arches and processes - with the help of ligaments.

In the composition of each intervertebral disc, the central and peripheral parts are distinguished. The central part of the disc is called the nucleus pulposus (nucleus pulposus), and the peripheral part of - the fibrous ring (anulus fibrosus). The gelatinous nucleus, which is the remainder of the dorsal string (chorda), plays the role of a shock absorber between the bodies of two adjacent vertebrae. Sometimes inside the gelatinous nucleus there is a horizontal narrow slit, which makes it possible to call such a connection a symphysis (semi-joint). The peripheral part of the intervertebral disc (fibrous ring) is constructed of fibrous cartilage, which is firmly fused with the bodies of the vertebrae.

The thickness of the intervertebral disc depends on the level of its location and mobility of the corresponding part of the spine. In the thoracic region, the least mobile, the thickness of the disc is 3-4 mm, in the cervical region, which has greater mobility, 5-6 mm; In the lumbar region, the thickness of the disc is 10-12 mm.

The connection of the vertebral bodies is supported by the anterior and posterior longitudinal ligaments.

Anterior longitudinal ligament (lig. Longitudinale anterius) runs along the anterior surface of the vertebral bodies and intervertebral discs. This ligament begins on the pharyngeal tubercle of the occipital bone and the anterior tubercle of the anterior arch of the atlas and ends at the level of the 2-3rd transverse lines of the sacrum. The ligament firmly fuses with the intervertebral discs and loose - with the bodies of the vertebrae.

The posterior longitudinal ligament (lig. Longitudinale posterius) runs inside the vertebral canal along the posterior surface of the vertebral bodies from the axial vertebra to the first coccygeal vertebra. At the level of the medial atlanto-osseous joint, this ligament is connected to the cruciate ligament of the atlant, and joins it to the intervertebral discs from it.

Arcs of adjacent vertebrae are connected by means of yellow ligaments (ligg. Flava), consisting mainly of elastic connective tissue, which has a yellowish color. These ligaments are strong, resilient.

The articular processes form arcuate (intervertebral) joints (artt zygapophysiales, S. Intervertebrales). The planes of the location of joint joints of these joints correspond to the orientation of the articular processes of the adjacent vertebrae of the cervical, thoracic and lumbar spine. Separately examined lumbosacral joints (artt. Lumbosacrales), formed by the lower articular processes of the V lumbar vertebra and the upper articular processes of the sacrum.

All arcuate joints refer to flat, inactive joints, which is facilitated by a tight tension of the capsule, which is attached to the edges of the joint surfaces.

The spinous processes of the vertebrae are interconnected by interintenal ligaments (ligg. Interspinale) and an adnate ligament {lig. Supraspinale). The interstitial ligaments are thick fibrous plates located between the spinous processes. A ligamentous ligament is attached to the apices of the spinous processes of all the vertebrae. In the cervical region, this ligament is called the ligament (lig. Nuchae). The posterior margin of the bony ligament lies between the outer occipital protrusion at the top and the apices of the spinous processes of the vertebrae below.

Between the transverse processes of the vertebrae there are interdigitic ligaments connecting them (ligg. Intertransversaria) (Fig. 91). In the cervical spine, these ligaments are often absent.

The sacrococcygeal joint (art sacrococcygea) is a junction of the tip of the sacrum with the first coccygeal vertebra. Often there is a gap in the intervertebral disc of this joint. The connection of the sacrum with the coccyx is strengthened with the help of several ligaments. The paired lateral sacrococcygeal ligament (lig. Sacrococcygeum laterale) extends from the lower edge of the lateral sacral crest to the transverse process of the first coccygeal vertebra. It is analogous to inter-transverse ligaments. Ventral sacrococcygeal ligament (lig. Sacrococcygeum ventrale) is the continuation of the anterior longitudinal ligament. The superficial dorsal sacrococcygeal ligament (lig. Sacrococcygeum dorsale superficiale) extends from the edge of the sacral slit to the back of the coccyx. The deep dorsal sacrococcygeal ligament (lig. Sacrococcygeum dorsale profundum), being an extension of the posterior longitudinal ligament, is located on the posterior surface of the bodies of the V sacral and I coccygeal vertebrae. Sacral and coccygeal horns are connected together by means of connective tissue (syndesmosis). Mobility in the sacrococcygeal joint is more pronounced in women. During childbirth, some deviation of the coccyx is possible, which increases the size of the birth canal.

[1], [2], [3]