These joints are comprised of two uncinate processes—one rising from the top of each side of the vertebral body—that fit in indentations in the vertebral body above. Compared to the facet joints, the uncovertebral joints are relatively small and not present at birth. The uncovertebral joints typically develop by age While the vertebrae provide the neck with stability and protection, these bones are held together and supported by soft tissues as discussed on the next page.
Stiff Neck Causes, Symptoms, and Treatment. You are here Conditions Spine Anatomy. Cervical Vertebrae share pin it Newsletters. Peer Reviewed. Cervical region. In: Chila A, ed. Palipana, D. Atypical cervical vertebrae. Reference article, Radiopaedia. Spine , Musculoskeletal. URL of Article. Snell RS. Clinical Anatomy By Regions Internationa. Read it at Google Books - Find it at Amazon. Related articles: Anatomy: Spine. Promoted articles advertising.
Figure 1: atlas Gray's illustration Figure 1: atlas Gray's illustration. Figure 2a: axis Gray's illustration Figure 2a: axis Gray's illustration. Figure 2b: axis Gray's illustration Figure 2b: axis Gray's illustration. Loading more images The single spinous process vertebral spine projects posteriorly at the midline of the back. The vertebral spines can easily be felt as a series of bumps just under the skin down the middle of the back. The transverse and spinous processes serve as important muscle attachment sites.
A superior articular process extends or faces upward, and an inferior articular process faces or projects downward on each side of a vertebrae. The paired superior articular processes of one vertebra join with the corresponding paired inferior articular processes from the next higher vertebra.
These junctions form slightly moveable joints between the adjacent vertebrae. The shape and orientation of the articular processes vary in different regions of the vertebral column and play a major role in determining the type and range of motion available in each region. In addition to the general characteristics of a typical vertebra described above, vertebrae also display characteristic size and structural features that vary between the different vertebral column regions.
Thus, cervical vertebrae are smaller than lumbar vertebrae due to differences in the proportion of body weight that each supports.
Thoracic vertebrae have sites for rib attachment, and the vertebrae that give rise to the sacrum and coccyx have fused together into single bones. Typical cervical vertebrae , such as C4 or C5, have several characteristic features that differentiate them from thoracic or lumbar vertebrae Figure 6.
Cervical vertebrae have a small body, reflecting the fact that they carry the least amount of body weight. Cervical vertebrae usually have a bifid Y-shaped spinous process. The spinous processes of the C3—C6 vertebrae are short, but the spine of C7 is much longer. You can find these vertebrae by running your finger down the midline of the posterior neck until you encounter the prominent C7 spine located at the base of the neck. The transverse processes of the cervical vertebrae are sharply curved U-shaped to allow for passage of the cervical spinal nerves.
Each transverse process also has an opening called the transverse foramen. An important artery that supplies the brain ascends up the neck by passing through these openings. The superior and inferior articular processes of the cervical vertebrae are flattened and largely face upward or downward, respectively. The first and second cervical vertebrae are further modified, giving each a distinctive appearance. The first cervical C1 vertebra is also called the atlas , because this is the vertebra that supports the skull on top of the vertebral column in Greek mythology, Atlas was the god who supported the heavens on his shoulders.
The C1 vertebra does not have a body or spinous process. Instead, it is ring-shaped, consisting of an anterior arch and a posterior arch. The transverse processes of the atlas are longer and extend more laterally than do the transverse processes of any other cervical vertebrae. The superior articular processes face upward and are deeply curved for articulation with the occipital condyles on the base of the skull.
The inferior articular processes are flat and face downward to join with the superior articular processes of the C2 vertebra. The second cervical C2 vertebra is called the axis , because it serves as the axis for rotation when turning the head toward the right or left. The axis resembles typical cervical vertebrae in most respects, but is easily distinguished by the dens odontoid process , a bony projection that extends upward from the vertebral body.
The dens joins with the inner aspect of the anterior arch of the atlas, where it is held in place by transverse ligament. The bodies of the thoracic vertebrae are larger than those of cervical vertebrae Figure 6. The characteristic feature for a typical midthoracic vertebra is the spinous process, which is long and has a pronounced downward angle that causes it to overlap the next inferior vertebra. The superior articular processes of thoracic vertebrae face anteriorly and the inferior processes face posteriorly.
These orientations are important determinants for the type and range of movements available to the thoracic region of the vertebral column.
Thoracic vertebrae have several additional articulation sites, each of which is called a facet , where a rib is attached.
These are for articulation with the head end of a rib. An additional facet is located on the transverse process for articulation with the tubercle of a rib. Lumbar vertebrae carry the greatest amount of body weight and are thus characterized by the large size and thickness of the vertebral body Figure 6.
They have short transverse processes and a short, blunt spinous process that projects posteriorly.
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