How many articulations on t1

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. In addition to those in general practice, some chiropractors specialize in sport injuries, neurology, orthopaedics, pediatrics, nutrition, internal disorders, or diagnostic imaging.

Citation, DOI and article data. Palipana, D. Typical thoracic vertebrae. Reference article, Radiopaedia. Typical dorsal vertebra Typical dorsal vertebrae Typical thoracic vertebra.

URL of Article. On this page:. Quiz questions. DSc SSP. Gray's Anatomy. Churchill Livingstone. Read it at Google Books - Find it at Amazon 2. Last's Anatomy. Read it at Google Books - Find it at Amazon 3.

McMinn and Abrahams' clinical atlas of human anatomy. Read it at Google Books - Find it at Amazon 4. Snell RS. Vertebral bodies increase in size from superior to inferior. The vertebral body consists of a trabecular bone, which contains the red marrow, surrounded by a thin external layer of compact bone.

The arch, along with the posterior aspect of the body, forms the vertebral spinal canal, which contains the spinal cord. The arch consists of bilateral pedicles, cylindrical segments of bone that connect the arch to the body, and bilateral lamina, bone segments form most of the arch, connecting the transverse and spinous processes.

A typical vertebra also contains four articular processes, two superior and two inferior, which contact the inferior and superior articular processes of adjacent vertebrae, respectively. The point at which superior and articular facets meet is known as a facet, or zygapophyseal, joint.

These maintain vertebral alignment, control the range of motion, and are weight-bearing in certain positions. The spinous process projects posteriorly and inferiorly from the vertebral arch and overlaps the inferior vertebrae to various degrees, depending on the region of the spine.

Lastly, two transverse processes project laterally from the vertebral arch in a symmetric fashion. Typical thoracic vertebrae have several features distinct from those typical of cervical or lumbar vertebrae. The primary characteristic of the thoracic vertebrae is the presence of costal facets.

Cervicothoracic Trauma: Diagnosis and Treatment. Seminars in Spine Surgery. Wang VY, Chou D. The cervicothoracic junction. Neurosurg Clin N Am. Techy F, Benzel EC. Stabilization of the Cervicothoracic Junction. Contemporary Spine Surgery. Mini-open anterior approach for cervicothoracic junction fracture: technical note.

Neurosurgical Focus.