Page 95 - Anatomy and Physiology of Farm Animals, 8th Edition

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the vertebral foramen. The first cervical from the arch and provide attachment sites
Transverse processes project laterad
vertebra, the atlas, lacks a body.
VetBooks.ir bral foramen, which contains the spinal for muscles that move the vertebral col-
Dorsally, the arch completes the verte-
umn. The transverse processes of the
cord. When vertebrae are placed in series, lumbar vertebrae are especially large.
the adjacent vertebral foramina form the The intervertebral foramina are cre-
vertebral canal, through which the spinal ated by the alignment of notches on adja-
cord runs longitudinally. cent vertebral arches, creating an opening
Cranial and caudal articular processes between these vertebrae. Spinal nerves exit
form joints between adjacent vertebrae; in the vertebral canal via the intervertebral
the thoracic region they also form joints foramina on their way to innervating
with the ribs. All of these articulations are peripheral structures.
typical synovial joints (see Chapter 6). The cervical vertebrae have well‐
The spinous process projects dorsad developed articular processes to accom-
from the arch of the vertebra. The modate the large range of motion of the
spinous processes provide important neck. All domestic mammals have seven
attachment sites for epaxial muscles. In cervical vertebrae.
ungulates, the very tall spinous processes The atlas is the first cervical vertebra
of the first few thoracic vertebrae form a (Fig. 4‐9). The spinous process and body
dorsal prominence to which is anchored are absent. The atlas articulates with the
the nuchal ligament (see Fig. 7‐18) for occipital condyles of the skull cranially and
support of the head. In horses, the prom- with the axis caudally.
inence in this location is called the The axis is the second cervical vertebra
withers. (Fig. 4‐9). The spinous process forms a

Typical vertebra
Transverse
foramen
Spinous process

Transverse process
Vertebral foramen

Arch
Body
Cervical
vertebra

Thoracic Lumbar
vertebra vertebra

Figure 4-8. Representative vertebrae, viewed from the cranial aspect.