(5)
The processes consist of the following:
(a) A spinous process that is directed dorsally and is formed at the
junction of the two laminae.
(b) Two transverse processes that project laterally and are formed at
the junction of the pedicles and laminae.
(c) Two superior articular (apophyseal) processes (with articular
surfaces) that project upward and face dorsally.
(d) Two inferior articular (apophyseal) processes (with articular
surfaces) that project downward and face ventrally.
c. Articulation of Typical Vertebrae. A typical vertebra articulates with
contiguous vertebrae as follows:
(1) The superior and inferior surfaces of the body articulate with the bodies
of the adjacent superior and inferior vertebrae through intervertebral disks of elastic
fibrocartilage interposed between the bodies of the articular vertebrae to act as
cushions.
(2) The articular surfaces of the superior articular processes articulate with
the articular surfaces of the inferior articular processes of the vertebra above.
(3) The articular surfaces of the inferior articular processes articulate with
the articular surfaces of the superior articular processes of the vertebra below.
2-19. DIFFERENTIATING CHARACTERISTICS OF TYPICAL VERTEBRAE BY
REGIONS
a. Cervical Vertebrae. C-3 to C-7 (figure 2-19A) have small oval-shaped
bodies and the spinous processes of all these, except C-7, are short and bifid (cleft).
C-7 has a long, thick, prominent, nonbifurcated process that is a vertebral landmark.
Each of the cervical vertebrae has a hole in the transverse process called the
transverse foramen.
b. Thoracic Vertebrae. The thoracic vertebrae, designated as T-1 to T-12
(figure 2-19B) have large bodies. Their spinous process point inferiorly and all of them
present facets (most also demifacets) on the lateral aspects of their bodies that
articulate with the ribs.
c. Lumbar Vertebrae. Vertebrae designated L-1 to L-5 (figure 2-19C) have
very large bodies. Their spinous processes are broad and project horizontally. The
superior articular process presents on its posterior margin, the mammillary process.
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