Anterior Cervical
Triangle 1
 To describe the anterior cervical triangle.
 To list the contents of this triangle.
 To describe the carotid sheath & its relations.
Anterior cervical triangle is divided into:
1) Carotid triangle
3
2) Submandibular triangle
2
1
3) Submental triangle
4) Muscular triangle
4
Carotid triangle:
Common carotid artery (CCA):
Arises from the brachiocephalic
trunk on the right & from aortic arch
on the left side
Ascends in the carotid sheath
with the IJV & vagus nerve
Ends at C3-4 by dividing into ECA
& ICA
Gives no branches
CCA pulse is best felt between
trachea & strap muscles
Carotid sinus:
-Dilatation at carotid bifurcation
-Contain baroreceptors
Carotid body:
-A mass of chemoreceptor cells in
the sinus
BOTH are supplied by the sinucarotid branch of IX nerve
Carotid body tumor:
A pulsetile swelling on the side of
the neck
Carotid massage
Afferent by IX nerve
Medulla oblongata
Efferent by X nerve to
the cardiac plexus
Bradycardia
Hypotension
Carotid reflex
Internal carotid artery (ICA):
•Lies posterior to the ECA
•Enters the carotid canal (petrous bone) at skull base
•Passes inside cavernous sinus in the middle cranial fossa
•Supplies the brain & orbital structures
•It gives no branch in the neck
External carotid artery (ECA):
•Ascends anterior to ICA
•It is the artery of head & neck giving 8
branches
•Ends behind the neck of the mandible by
dividing into its 2 terminal branches
Anterior branches:
1- Superior thyroid artery:
-Descends with the external laryngeal nerve
-Gives superior laryngeal artery to the larynx
-Enters the apex of thyroid lobe
-Supplies thyroid & parathyroid glands
2- Lingual artery:
-Directed to the oral cavity after an upward loop
-XII nerve lies lateral to it
-Supplies the tongue & structures in the floor of
the mouth
3- Facial artery:
-Crosses the submandibular triangle before reaching the face
-Supplies the tonsils, palate & submandibular gland
-Enters the face by turning below the lower border of the mandible
Posterior branches:
4- Occipital artery:
-Crosses the apex of posterior triangle
-Supplies the back of scalp
5- Posterior auricular artery:
-Lies superficial to the mastoid process
-Supplies the auricle
-Gives stylomastoid branch to the middle ear
Medial branch:
6- Ascending pharyngeal artery:
Ascends along pharyngeal wall
Terminal branches:
7- Superficial temporal artery:
Ascends upward to the temporal fossa
8- Maxillary artery:
Passes forward to the infratemporal fossa
Internal jugular vein (IJV):
Emerges from jugular foramen
Lies posterior to the catotid
artery at the skull base & lateral to
it at the root of the neck
The part of the carotid sheath
surrounding it is almost deficient
Ansa cervicalis & deep cervical
nodes are closely related to it
Ends
by
subclavian
uniting
vein
brachiocephalic vein
with
the
forming
the
2
Tributaries:
1
4
1- Inferior petrosal sinus
2- Occipital veins
3
3- Thyroglossofacial veins
4- Pharyngeal veins
5- Middle thyroid vein
5
Vagus nerve:
•Leaves the jugular foramen &
descends in the carotid sheath
•Takes the cranial part of XI which
is distributed to pharyngeal &
laryngeal muscles
•Has two ganglia
•Contains
the
major
parasympathetic power in the
body (70%)
•Branches:
1
2
1- Meningeal; to the meninges
3
2- Auricular; to the external ear
4
3- Pharyngeal: to muscles of the
pharynx & soft palate
5
4- Superior laryngeal; to the
larynx
5- Cervical cardiac nerve; to the
cardiac plexuses in the thorax
6- Recurrent laryngeal; to the
larynx
6
Hypoglossal nerve (XII):
Crosses lateral to the ECA in its
way to the floor of the mouth
Branches in the neck are of C1
origin:
-Ansa superior root
-Nerve to thyrohyoid
-Nerve to geniohyoid
Enters the floor of the mouth to
supply all tongue muscles except
palatoglossus
Hypoglossal nerve injury causes deviation of the tongue
to the .?. side
Submandibular triangle:
Digastric:
Origin:
-Anterior belly: digastric fossa
-Posterior belly: digastric notch
Insertion:
Intermediate tendon, hyoid bone
Nerve supply:
-Anterior belly: myelohyoid n. (Vc)
-Posterior belly: facial nerve (VII)
Action:
-Elevate the hyoid bone
-Opens the mouth widely
Stylohyoid:
-From the styloid process to the hyoid bone
-Overlies the posterior belly of digastric with
the same innervation & action
Mylohyoid:
Origin: mylohyoid line
Insertion: mylohyoid raphe & hyoid bone
Nerve supply: nerve to mylohyoid
Action:
-Forms the floor of the mouth
-Plays a major role in swallowing
Hyoglossus:
Origin: greater cornu of the hyoid
Insertion: side of the tongue
Nerve supply: XII nerve.
Action:
-Elevates the hyoid
-Depresses the tongue
Contents of the triangle:
1- Submandibular gland
2- Facial artery:
-Crosses the triangle in S shape
course
3
2
-Before reaching the face it supplies
the gland, tonsils & palate
3- Common facial vein:
-Anterior facial + anterior division of
retromandibular veins
-Passes superficial to the gland
-Drains to the IJV
4- Submandibular lymph nodes
5- Cervical branch of VII
4
1
Ludwig’s angina:
Cellulitis
(inflammation
of
the
soft
tissues) of the submandibular triangle &
floor of the mouth
May cause airway obstruction
Submental triangle:
Boundaries:
-Digastric anterior bellies
-Hyoid
Contents:
1- Submental branch of facial artery.
2- beginning of AJV.
3- Submental lymph nodes.
4- Nerve to myelohyoid:
Submental swellings