DAY 3 LT 5.11 Name the parts of a typical vertebra, and explain in general how the cervical, thoracic, and lumbar vertebrae differ from one another (Axial Skeleton). (Page 150, Figure 5.16, Slides 80-83)

Vertebral Arch

Arch formed from the joining of all posterior extensions, the laminae and pedicles, from from the vertebral body.

Vertebral Foramen

Canal through which the spinal cord passes.

Body or Centrum

Discllike, weight-bearing part of the vertebra facing anteriorly in the vertebral column.

Superior and Inferior Articular Processes

Paired projections lateral to the vertebral foramen, allowing a vertebra to form joints with adjacent vertebrae.

Spinous Process

Single projection arising from the posterior aspect of the vertebral arch (actually the fused laminae).

Lumbar Vertebrae

The five vertebrae have massive, blocklike bodies. Their short, hatchet-shaped spinous processes make them look like a moose head from the lateral aspect. Since most of the stress on the vertebral column occurs in the lumbar region, these are the sturdiest of the vertebrae.

Cervical Vertebrae

The seven cervical vertebrae form the neck region of the spine. The first two vertebrae (atlas and axis) are different because they perform functions not shared by the other cervical vertebrae. The atlas has no body. The superior surfaces of its transverse processes contain large depressions that receive the occipital condyles of the skull. This joint allows you to nod "yes". The axis acts as a pivot for the rotation of the atlas (and skull) above. It has a large upright process, the dens, or odontoid process, which acts as the pivot point. The "typical" cervical vertebrae are the smallest, lightest vertebrae, and most often their spinous processes are short and divided into two branches. The transverse processes of the cervical vertebrae contain foramina (openings) through which the vertebral arteries pass on their way to the brain above. Any time you see these foramina in a vertebrae, you should know immediately that it is a cervical vertebra.

Thoracic Vertebrae

The thoracic vertebrae are all typical. They are larger than the cervical vertebrae. The body is somewhat heart-shaped and has two costal facets (articulating surfaces) on each side, which receive the heads of the ribs. The spinous processes is long and hooks sharply downward, causing the vertebra to look like a giraffe's head viewed from the side.

Transverse Processes

Two lateral projections from the vertebral arch.