Transverse foramen The first cervical vertebrae C-1 is known as the atlas. Thoracic Spine The spinous processes of thoracic vertebrae are long and slender, and project sharply downward. Facets and demifacets are surfaces where ribs attach to all of the vertebral bodies except the 11th and 12th.
This lateral sagittal MRI image of the thoracic spine shows a mass at the level of T It is pressing against the spinal cord. Transverse process. Superior articular process. Inferior articular process. Spinous process. Vertebral foramen. Edit article. View revision history Report problem with Article. Citation, DOI and article data. Luijkx, T. Typical cervical vertebrae.
Reference article, Radiopaedia. Musculoskeletal , Spine. URL of Article. On this page:. McMinn's clinical atlas of human anatomy. In the intact vertebral column, the vertebral foramina of all of the vertebrae align to form the vertebral spinal canal , which serves as the bony protection and passageway for the spinal cord down the back.
When the vertebrae are aligned together in the vertebral column, notches in the margins of the pedicles of adjacent vertebrae together form an intervertebral foramen , the opening through which a spinal nerve exits from the vertebral column Figure. Seven processes arise from the vertebral arch.
Each paired transverse process projects laterally and arises from the junction point between the pedicle and lamina. 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.
Intervertebral Disc The bodies of adjacent vertebrae are separated and united by an intervertebral disc, which provides padding and allows for movements between adjacent vertebrae. The disc consists of a fibrous outer layer called the anulus fibrosus and a gel-like center called the nucleus pulposus.
The intervertebral foramen is the opening formed between adjacent vertebrae for the exit of a spinal nerve. Regional Modifications of Vertebrae 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.
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. Thoracic Vertebrae The bodies of the thoracic vertebrae are larger than those of cervical vertebrae Figure.
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.
Rib Articulation in Thoracic Vertebrae Thoracic vertebrae have superior and inferior articular facets on the vertebral body for articulation with the head of a rib, and a transverse process facet for articulation with the rib tubercle. Lumbar Vertebrae Lumbar vertebrae carry the greatest amount of body weight and are thus characterized by the large size and thickness of the vertebral body Figure. They have short transverse processes and a short, blunt spinous process that projects posteriorly.
The articular processes are large, with the superior process facing backward and the inferior facing forward. Sacrum and Coccyx The sacrum is a triangular-shaped bone that is thick and wide across its superior base where it is weight bearing and then tapers down to an inferior, non-weight bearing apex Figure.
It is formed by the fusion of five sacral vertebrae, a process that does not begin until after the age of On the anterior surface of the older adult sacrum, the lines of vertebral fusion can be seen as four transverse ridges.
Similarly, the fused transverse processes of the sacral vertebrae form the lateral sacral crest. The sacral promontory is the anterior lip of the superior base of the sacrum. Lateral to this is the roughened auricular surface, which joins with the ilium portion of the hipbone to form the immobile sacroiliac joints of the pelvis. Passing inferiorly through the sacrum is a bony tunnel called the sacral canal , which terminates at the sacral hiatus near the inferior tip of the sacrum.
Each of these openings is called a posterior dorsal sacral foramen or anterior ventral sacral foramen. These openings allow for the anterior and posterior branches of the sacral spinal nerves to exit the sacrum. The superior articular process of the sacrum , one of which is found on either side of the superior opening of the sacral canal, articulates with the inferior articular processes from the L5 vertebra.
The coccyx, or tailbone, is derived from the fusion of four very small coccygeal vertebrae see Figure. It articulates with the inferior tip of the sacrum. It is not weight bearing in the standing position, but may receive some body weight when sitting. Intervertebral Discs and Ligaments of the Vertebral Column The bodies of adjacent vertebrae are strongly anchored to each other by an intervertebral disc.
This structure provides padding between the bones during weight bearing, and because it can change shape, also allows for movement between the vertebrae. Although the total amount of movement available between any two adjacent vertebrae is small, when these movements are summed together along the entire length of the vertebral column, large body movements can be produced. Ligaments that extend along the length of the vertebral column also contribute to its overall support and stability.
An intervertebral disc is a fibrocartilaginous pad that fills the gap between adjacent vertebral bodies see Figure. Each disc is anchored to the bodies of its adjacent vertebrae, thus strongly uniting these. The discs also provide padding between vertebrae during weight bearing.
Because of this, intervertebral discs are thin in the cervical region and thickest in the lumbar region, which carries the most body weight. In total, the intervertebral discs account for approximately 25 percent of your body height between the top of the pelvis and the base of the skull. Intervertebral discs are also flexible and can change shape to allow for movements of the vertebral column. Each intervertebral disc consists of two parts.
The anulus fibrosus is the tough, fibrous outer layer of the disc. Inside is the nucleus pulposus , consisting of a softer, more gel-like material. 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. The articular processes are large, with the superior process facing backward and the inferior facing forward.
The sacrum is a triangular-shaped bone that is thick and wide across its superior base where it is weight bearing and then tapers down to an inferior, non-weight bearing apex Figure 6. It is formed by the fusion of five sacral vertebrae, a process that does not begin until after the age of The coccyx, or tailbone, is derived from the fusion of four very small coccygeal vertebrae see Figure 6.
It articulates with the inferior tip of the sacrum. It is not weight bearing in the standing position, but may receive some body weight when sitting. Watch this second animation to see one possible treatment for a herniated disc, removing and replacing the damaged disc with an artificial one that allows for movement between the adjacent certebrae.
How could lifting a heavy object produce pain in a lower limb? Use this tool to identify the bones, intervertebral discs, and ligaments of the vertebral column. The thickest portions of the anterior longitudinal ligament and the supraspinous ligament are found in which regions of the vertebral column?
Chiropractors are health professionals who use nonsurgical techniques to help patients with musculoskeletal system problems that involve the bones, muscles, ligaments, tendons, or nervous system. They treat problems such as neck pain, back pain, joint pain, or headaches. If needed, they will refer the patient to other medical specialists. Chiropractors use a drug-free, hands-on approach for patient diagnosis and treatment. They can recommend therapeutic or rehabilitative exercises, and some also include acupuncture, massage therapy, or ultrasound as part of the treatment program.
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