Anterior Triangle of the Neck Flashcards
Which neck triangle (anterior or posterior) does the carotid triangle lie within? What important structures are contained in the carotid triangle?
It is within the anterior triangle of the neck. The carotid arteries and internal jugular vein are found in the carotid triangle.
What are the borders of the submental triangle? What two things are contained in this triangle?
The two anterior bellies of the digastric muscle and the superior edge of the hyoid bone. Submental lymph nodes and small veins are in it.
How many suprahyoid muscles are there? How many infrahyoid muscles are there?
4 suprahyoid, 4 infrahyoid
Name the suprahyoid and infrahyoid muscles.
Suprahyoid:
- Mylohyoid muscle
- Digastric (anterior and posterior bellies - DUAL INNERVATION!)
- Stylohyoid
- Geniohyoid
Infrahyoid:
- Thyrohyoid
- Sternothyroid
- Sternohyoid
- Omohyoid (superior and inferior bellies)
Which suprahyoid muscle has dual innervation? Which nerves?
Digastric:
- Anterior belly is supplied by nerve to mylohyoid (branch of CN V3)
- Posterior belly is supplied by branches of the facial nerve (CN VII)
What are the actions of each of the four infrahyoid muscles?
Omohyoid depresses the hyoid bone.
Thyrohyoid brings together the hyoid bone and thyroid cartilage.
Sternohyoid depresses the hyoid bone.
Sternothyroid depresses the thyroid cartilage.
What nerves supply the infrahyoid muscles?
The ansa cervicalis + C1 via hypoglossal (the geniohyoid and thyrohyoid muscles)
Which nerve roots make up the ansa cervicalis?
C1, C2, C3
Describe the branches of the ansa cervicalis, including the muscles that each innervate.
Some C1 fibers run with CN XII in the hypoglossal canal and exit to supply the geniohyoid and thyrohyoid.
The superior root consists of C1 and C2 fibers and supply the sternohyoid and omohyoid superior belly.
The inferior root consists of C2 and C3 fibers and supply the sternothyroid and omohyoid inferior belly.
Which nerve runs between the internal jugular vein and common carotid artery?
The vagus nerve
Where do the common carotid arteries arise from? At what spinal level do they split into the internal and external carotid arteries?
The right common carotid is a branch of the right brachiocephalic artery. The left common carotid comes off the aortic arch. They split into the internal and external carotid arteries at C4/C5 - the same level as the top of the thyroid cartilage.
What nerve is at risk when ligating a thyroid tumor? Where does this nerve lie in relation to the inferior thyroid artery?
The recurrent laryngeal nerve is at risk. It lies immediately posterior to the inferior thyroid artery behind the thyroid gland.
What nerve runs down the anterior aspect of the anterior scalene muscle?
Phrenic nerve
Describe the branches of the internal carotid artery in the neck.
This is a trick! It has none, it goes up to supply the brain.
Name the branches of the external carotid artery as they come off from inferior to superior.
SALFOPSMax
superior thyroid ascending pharyngeal lingual facial occipital posterior auricular superficial temporal maxillary