Unit 17 Anterior Triangle of the Neck Flashcards
(100 cards)
What are the boundaries of the anterior triangle of the neck?
boundaries
1. Superior (base of the triangle): inferior and posterior borders of mandible on
each side
2. posterior: anterior border of the sternocleidomastoid
3. anterior: median line of the neck
What are the four divisions of the anterior triangle of the neck?
muscular, carotid, submental and digastric or submandibular
What are the boundaries of the muscular division?
bounded by the anterior border of the
sternocleidomastoid muscle, the superior belly of the omohyoid muscle and the median line

What are the four “strap” muscles? What do they act on?
Called infrahyoid muscles: sternohyoid muscle, omohyoid muscle, sternothyroid muscle, thyrohyoid muscle; they act on the larynx and the hyoid bone
From where does the sternohyoid muscle arrise? Where does it insert?
It arrises from the thorax behind the manubrium, it inserts on the hyoid bone
From where does the omohyoid arise? Where does it insert?
It arises near the suprascapular notch and inserts on the hyoid bone
What is the structure of the omohyoid muscle?
Has superior and inferior bellies with an intermediate tendon
Where does the sternothyroid muscle arise? Where does it insert?
It arises from the posterior manubrium..below the origin of the sternohyoid muscle. It inserts on the oblique line of thryroid cartilage
What three muscles act as a depressor of the larynx as a whole?
Sternohyoid, sternothyroid, and omohyoid
What are the three depressors of the larynx innervated by?
The sternothyroid, sternohyoid, and omohyoid are all innervated by branches of the ansa cervicalis
What muscle opposes the depressors of the larynx, and therefore elevates the larnyx as a whole?
the thyrohyoid
From where does the thyrohyoid arise? Where does it insert?
arises from the oblique line of thyroid cartilage and inserts on the hyoid bone
What innervates the elevator of the larynx?
The thyrohyoid is innervated by C1 fibers that run in the hypoglossal nerve (part of the ansa cervicalis)
What are the boundaries of the carotid division of the anterior triangle?
bounded by the posterior belly of the digastric muscle, the superior
belly of the omohyoid muscle, and the anterior border of the
sternocleidomastoid muscle

What is found within the carotid division of the anterior triangle of the neck?
The division of the common carotid into the internal and external carotid arteries. At the level of the common carotid we have the carotid sheath with the internal juglar vein and vagus nerve.
At what level does the common carotid divide into the internal and external carotid arteries?
upper border of the thyroid cartilage
What internal carotid branches are found in the neck?
NONE!
What are the branches of the external carotid artery in the neck?
superior thyroid, lingual artery, facial artery, ascending pharyngeal artery, occipital artery,
terminal branches: i. maxillary artery
ii. superficial temporal artery

What is the first branch of the external carotid? What branches from this artery?
The first branch is the superior thyroid, and its first branch is the superior laryngeal artery
What does the superior laryngeal artery travel with, and through what structure?
Travels with the internal branch of the superior laryngeal NERVE through the thyrohyoid membrane
What is the “second”anterior branch of the external carotid artery, and where does it run?
the lingual artery: passes deep to the hypoglossus muscle and immediately above the hyoid bone
What is the “third” anterior branch of the external carotid and where does it run?
facial artery: may come off in common with lingual artery; passes deep to the submandibular gland before crossing external to the mandible to enter the face; in neck it gives branches
What are the branches of the facial artery?
i. glandular branches
ii. submental branch which accompanies the nerve to the mylohyoid muscle
iii. tonsilar and ascending palatine branches (not seen in this dissection)
What is the “first” posterior branch of the external carotid, and where does it run?
ascending pharyngeal artery: lies on the wall of the pharynx