ANTERIOR TRIANGLE
of the NECK
Borders

Superior:
Mandible.

Posterior:
Sternocleidomastoid (anterior border).

Anterior:
Midline of the neck.
Subdivisions
Muscular triangle.
 Submandibular triangle.
 Carotid triangle.

Contents of Muscular Triangle

Digastric:
Anterior and posterior bellies.
Innervated by two different cranial nerves.
Stylohyoid.
 Mylohyoid.

Contents of Muscular Triangle
Geniohyoid.
 Sternohyoid.
 Sternothyroid.
 Thyrohyoid.
 Omohyoid.

Carotid System


Common carotid.
Bifurcation:
Blood monitors:
Carotid sinus:
Dilated terminal portion of common
carotid.
Baroreceptor.
Carotid body:
Chemoreceptor.
Internal carotid:
Has no branches in the neck.
External carotid.
External Carotid Branches



Superior thyroid (anterior).
Ascending pharyngeal (medial).
Lingual (anterior):
Crossed by hypoglossal nerve at its origin.





Facial (anterior).
Occipital (posterior).
Posterior auricular (posterior).
Superficial temporal (terminal).
Maxillary (terminal).
Characteristics and Branches of
Cervical Plexus



From ventral rami of C1-4.
Hypoglossal nerve (CN XII).
Sensory branches:
Great auricular (C2-3).
Lesser occipital (C2(3)):
Ventral ramus of C2.
Greater occipital is dorsal ramus of C2.
Transverse cervical (C2-3).
Supraclavicular (C3-4).
Characteristics and Branches of
Cervical Plexus

Motor branches:
To prevertebral muscles:
See syllabus.
To levator scapulae muscle (C3-4).
To scalene muscles.
Ansa cervicalis:
Supplies infrahyoid muscles.
Except thyrohyoid.
Phrenic nerve (C3,4,5).
Ansa Cervicalis

Nerve to geniohyoid:
C1 via hypoglossal nerve.
Nerve to thyrohyoid.
 Superior and inferior roots:

Omohyoid.
Sternothyroid.
Sternohyoid.
Deep Neck

Subclavian artery:
Review from syllabus.

Scalene muscles:
Review from syllabus.




Thyroid gland.
Trachea.
Esophagus.
Thoracic duct and right lymphatic duct.
Deep Neck

Branches of vagus nerve:
Review from syllabus.

Sympathetic trunk:
Ascends on anterior surfaces of longus colli and
longus capitis muscles.
Lies posterior to common and internal carotids.
Lies deep to carotid sheath.
Contains preganglionic sympathetic fibers from T1
and T2 and T2 and GVA fibers as well from same
levels.
Sympathetic Trunk Ganglia

Superior cervical ganglion:
Elongated structure on longus capitis
muscle.
At level of C1 and C2.
Postganglionic sympathetic fibers from
this ganglion supply all smooth
muscles and glands of the head.
Sympathetic Trunk Ganglia
Middle cervical ganglion.
 Inferior cervical ganglion.
 Stellate ganglion:

Fused inferior cervical ganglion and T1
ganglion.