Vertebrae are bony elements that in their entirety constitute the spinal column. They have an important function in the support and movement apparatus of the human body, provide the attachment points for muscles and ligaments via their processes and protect the spinal cord running in their spinal canal with their solid structure. In addition to injuries, degenerative changes caused by incorrect loading and/or wear are primarily responsible for blockages or pain conditions in the area of the vertebrae.
What are vertebrae?
Schematic anatomical representation of the spine and its structure, as well as the vertebrae. Vertebrae are the bony structures of the body, which in the totality of all elements constitute the basic framework of the spine, in the channel of which runs the spinal cord. The human spine is composed of 32 to 34 of these basic elements and is divided into five sections based on the location of the vertebrae: Seven vertebrae (cervical vertebrae or vertebrae cervicales: C1 to C7) make up the cervical spine, twelve vertebrae (thoracic vertebrae or vertebrae thoracicae: Th to Th 12) make up the thoracic spine, and five vertebrae (lumbar vertebrae or vertebrae lumbales: L1 to L5) make up the lumbar spine. In addition, there are the five fused vertebrae (sacral vertebrae or vertebrae sacrales) of the sacrum and – individually differently laid out – three to five vertebrae (coccygeal vertebrae or vertebrae coccygeae), which together form the coccyx and are only very rudimentary in humans.
Anatomy and structure
The largest component of the vertebra is the vertebral body (corpus vertebrae), which provides the actual support function of the spine due to its mass. The vertebral bodies have a base and a top plate and are each separated by the intervertebral disc (also known as the intervertebral disc). The vertebral arch (arcus vertebrae) originates at the back of the vertebral bodies and forms the vertebral foramen (foramen vertebrae) together with the body. All vertebral holes on top of each other form the vertebral canal (Canalis vertebralis), in which the sensitive spinal cord runs and is protected all around. Two intervertebral foramen each allow the spinal cord fibers to exit to the body structures to be supplied. Three processes originate from the vertebra – two transverse processes (processus transversus) and the spinous process (processus spinosus), which is usually easily palpable on the back. The processes serve mainly for the attachment of ligaments and muscles. The first cervical vertebra, also known as the “atlas,” does not have a spinous process. While the atlas is connected to the second cervical vertebra “axis” by a so-called wheel joint, the other (non-fused) vertebrae are connected by four articular processes (processus articulares) each.
Function and tasks
The vertebrae perform important functions in the body – both in terms of the functionality of the support and movement system and the protection of the spinal cord. By joining the individual basic elements together, they form the spinal column. By means of special vertebral shapes, they provide for physiological curvatures of the spine and thus, in interaction with the intervertebral discs, enable effective absorption of impact loads. With their numerous articulated connections, the vertebrae enable a wide range of extension, flexion and rotation movements, also in combination. The vertebrae provide the necessary attachment points for the muscular and ligamentous apparatus via their processes. The important supply of fibers from the spinal cord to the individual body systems is also provided by the vertebrae: They protect the sensitive spinal nerves through their spinal canal and direct them to the corresponding body structures via their own exit holes from the vertebrae.
Diseases and complaints
The classic complaints in the vertebral region are due to injuries, wear and tear or diseases:
- Comminuted fractures of the vertebrae due to external force (for example, accidents or falls), with the risk of paraplegic syndrome in spinal cord injuries
- Osteoporosis of the vertebrae with the increasing risk of vertebral fracture.
- Wear reactions of the spine (osteochondrosis and spondylosis) due to many years of stress.
- Wear of the small vertebral joints (spondyloarthrosis) with the consequence of painful facet syndrome
- Narrowing of the spinal canal (spinal stenosis) due to wear and tear or tumors, with the risk of sensorimotor disturbances or paralysis due to crushing of the spinal cord
- Scheuermann’s disease (juvenile kyphosis): the spine, which is in the process of growth, reacts to incorrect loads with wedge vertebrae formation as well as collapses of the cover plates of the vertebral bodies and forms a painful hunchback.
- Vertebral slippage (spondylolisthesis) due to an instability of the spine.
- Inflammation of the vertebral bodies (spondylitis) – for example, due to bacterial infections or an underlying rheumatic disease.
- Herniated disc: here, parts of the intervertebral disc penetrate into the canal formed by the vertebrae, where they trigger the typical symptoms of spinal cord impairment, such as tingling, paralysis or pain.
