Cervical vertebrae

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Cervical vertebrae or Cervilar
Cervical vertebrae lateral2.png
Position of human cervical vertebrae (shown in red). It consists of 7 bones, from top to down, C1, C2, C3, C4, C5, C6 and C7.
Gray84.png
A human cervical vertebra
LatinVertebrae cervicales
Gray'ssubject #21 97
MeSHCervical+vertebrae
TAA02.2.02.001
FMAFMA:72063
 
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Cervical vertebrae or Cervilar
Cervical vertebrae lateral2.png
Position of human cervical vertebrae (shown in red). It consists of 7 bones, from top to down, C1, C2, C3, C4, C5, C6 and C7.
Gray84.png
A human cervical vertebra
LatinVertebrae cervicales
Gray'ssubject #21 97
MeSHCervical+vertebrae
TAA02.2.02.001
FMAFMA:72063

In vertebrates, cervical vertebrae (singular: vertebra) are those vertebrae immediately inferior to the skull.

Thoracic vertebrae in all mammalian species are defined as those vertebrae that also carry a pair of ribs, and lie caudal to the cervical vertebrae. Further caudally follow the lumbar vertebrae, which also belong to the trunk, but do not carry ribs. In reptiles, all trunk vertebrae carry ribs and are called dorsal vertebrae.

In many species, though not in mammals, the cervical vertebrae bear ribs. In many other groups, such as lizards and saurischian dinosaurs, the cervical ribs are large; in birds, they are small and completely fused to the vertebrae. The transverse processes of mammals are homologous to the cervical ribs of other amniotes.

In humans, cervical vertebrae are the smallest of the true vertebrae, and can be readily distinguished from those of the thoracic or lumbar regions by the presence of a foramen (hole) in each transverse process, through which passes the vertebral artery.

The remainder of this article focuses upon human anatomy.

General characteristics (C3-C6)[edit]

Side view of a typical cervical vertebra

By convention, the cervical vertebrae are numbered, with the first one (C1) located closest to the skull and higher numbered vertebrae (C2-C7) proceeding away from the skull and down the spine. The general characteristics of the third through sixth cervical vertebrae are described here. The first, second, and seventh vertebrae are extraordinary, and are detailed later.

Special cervical vertebrae (C1, C2, and C7)[edit]

Movements of the cervical spine[edit]

The movement of nodding the head takes place predominantly through flexion and extension at the joint between the atlas and the occipital bone, the atlanto-occipital joint. However, the cervical spine is comparatively mobile, and some component of this movement is due to flexion and extension of the vertebral column itself.

The movement of shaking or rotating the head left and right happens almost entirely at the joint between the atlas and the axis, the atlanto-axial joint. A small amount of rotation of the vertebral column itself contributes to the movement.

Landmarks[edit]

Base of Nose and the hard palate corresponds to C1.

Teeth (when mouth remains closed) correspond to C2.

Mandible and hyoid bone correspond to C3.

The thyroid cartilage is from C4 to C5.[1]

The cricoid cartilage is from C6 to C7.[1]

Clinical significance[edit]

Injuries to the cervical spine are common at the level of the second cervical vertebrae, but neurological injury is uncommon.

If it does occur, however, it may cause death or profound disability, including paralysis of the arms, legs, and diaphragm, which leads to respiratory failure.

Common patterns of injury include the odontoid fracture and the hangman's fracture, both of which are often treated with immobilization in a cervical collar or Halo brace.

A common EMS practice is to immobilize a patient's cervical spine to prevent further damage during transport to Medical Aid. This practice has come under review recently as incidence rates of unstable spinal trauma can be as low as 2% in immobilized patients. Canadian studies have developed the Canadian C-Spine Rule (CCR) for physicians to decide who should receive radiological imaging.[2]

Additional images[edit]

References[edit]

External links[edit]

This article incorporates text from a public domain edition of Gray's Anatomy.