Corpus: Vertebral arch

The vertebral arch is the arch-shaped section of a vertebra that attaches to the vertebral body and surrounds the larger part of the vertebral foramen.

The vertebral arches as a whole form the spinal canal and, as a flexible bone tube, protect the spinal cord contained within it from damage. They also support the articular processes of the vertebra, which guarantee the mobility of the spinal column. The processes of the vertebral arches serve as lever arms for the back muscles that attach here.

The vertebral arch differs functionally depending on its localisation in the spine (cervical, thoracic, lumbar). However, some structural principles are common to all vertebral arches.

The vertebral arch attaches to the vertebral body via strong feet (pediculi arcus vertebrae). Here there is a notch above and below (incisura vertebralis superior and inferior), which forms the intervertebral foramen with the next higher incisura of the neighbouring vertebra, through which the spinal nerves exit.

The continuation of the vertebral arch behind the two transverse processes (processus transversi) are the laminae arcus vertebrae. The two laminae fuse in the midline and thus close the vertebral arch. The unpaired spinous process (processus spinosus) arises at the fusion point.

Further projections on the vertebral arch are the 4 articular processes, two superior articular processes and two inferior articular processes. The section of bone between the upper and lower articular processes is called the interarticular process.

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