CHAPTER THREE 
CERVICAL REGION 
3.1 CERVICAL SKELETON 
The cervical vertebrae form a lordosis between 
the sixth cervical and second thoracic vertebrae 
(Fig. 3-1). There are seven cervical vertebrae {ver- 
tebrae cervicales) with a total length of 26.6 mm 
(Figs. 3-1, 3-2). The first vertebra, or atlas, has a 
ring shape (Fig. 3-3). Its outer and inner diameters 
are 14.1 and 10.3 mm, respectively. Dorsoventrally 
flattened, its external height is 8.2 mm- and its in- 
ternal height is 6.2 mm. The ventral side is thin and 
frail. The caudoventrally directed transverse proc- 
esses are perforated by the vertebral artery and vein, 
which pass through the transverse foramen {fora- 
men, transversarium). The second cervical vertebra, 
the axis or epistropheus, has a spinous process 
9.5 mm long (Fig. 3-4). Its length is 6.3 mm. The 
axis includes a body {corpus), odontoid process 
{dens), vertebral arch {arcus vertebrae), spinous 
process {processus spinosus), transverse processes 
{processus transversi) and articular processes {pro- 
cessus articulares). The dens, which is a cranial 
extension of the vertebral body supporting the atlas, 
is 9 mm long and 4.7 mm high. The vertebral arch 
is angled somewhat caudal to the vertebral body. 
It begins with a thin root above the base of the 
transverse process and broadens into a small, caudal 
articular process. From the dorsal posterior edge 
of the vertebral arch, a hatchet-shaped spinous 
process arises and elongates caudally, projecting 
over the third cervical vertebra (Fig. 3-1). A cranial 
projection touches the posterior 'ubercle of the atlas. 
The third to seventh cervical vertebrae are prac- 
tically identical. Their bodies are dorsoventrally 
flattened and shorter than those of the second ver- 
tebra. The dorsoventral obliquity of the articular 
ends of the vertebral bodies is partly responsible for 
the definite cervical lordosis. The thin spike-shaped 
transverse processes are perforated at their bases by 
transverse foramina. 
3.2 TOPOGRAPHY OF THE VENTRAL 
CERVICAL REGION 
The paired mandibular glands (Fig. 2-59) are 
prominent superficial structures of the ventral cer- 
vical region. The two glandular bodies press against 
each other in the median plane, and lateral to these 
glands is adipose tissue. This fat accumulation, 
along with the mandibular glands, covers the ven- 
tral cervical surface and the cranial portion of the 
thoracic musculature. The sternohyoid muscle {m. 
sternohyoideus) parallels the trachea on its ventral 
surface. Caudally, the sternohyoid muscle is covered 
at its origin on the manubrium by the sternocephalic 
muscle {m. sternocephalicus). The omotransver- 
sarius muscle {m. omotransversarius) originates 
on the acromion process of the scapula (Fig. 3-5), 
extends dorsal to the omohyoid muscle {m. omo- 
hyoideus), and continues to the cervical vertebrae. 
The digastric muscle (m. digastricus) lies cranial to 
the sternohyoid and omohyoid muscles (Figs. 3-6, 
3-7). 
The clavicle {clavicula){¥\^?,. 3-2, 3-9) separates 
the brachiocephalic muscle (m. brachiocephalicus) 
into a cleidobrachial muscle {m. cleidohrachialis) 
and a cleidocephalic muscle (m. cleidocephalicus) . 
The cleidobrachial muscle extends from the distal 
humerus to the lateral half of the clavicle in a fan- 
shaped array. The cleidocephalic muscle originates 
further medially on the clavicle, lies against the 
sternocephalic muscle laterally and extends with the 
latter to the skull. The sternocephalicus extends 
from its origin on the manubrium in a laterodorsal 
direction to the head and inserts on the occiput. The 
dorsal scalene muscle (m. scalenus dorsalis) con- 
nects the second, third, and fourth ribs with the 
transverse processes of the second, third, fourth and 
fifth cervical vertebrae. The middle scalene muscle 
(m. scalenus medius) extends ventral to the dorsal 
scalene muscle as a thin cervical muscle from the 
first rib to the third through fifth cervical vertebrae. 
The longus colli muscle lies between the trachea 
and the cervical vertebrae and extends caudally 
within the thoracic cavity to the fourth thoracic 
vertebra. The pectoralis muscles connect the sternal 
area with the humerus and form a triangular sur- 
face between the clavicle, the xiphoid process of the 
sternum and the humerus. 
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