Root of the Neck and Anterior Triangle of the Neck Flashcards
what 4 things does the neck contain that are important for life
thyroid gland, trachea, jugular vein, and carotid artery
why are many of the neck contents vulnerable to penetrating injuries
they lack bony protection
how is the hyoid bone suspended
by muscles and ligaments (stylohyoid)
what 2 things are suspended from the hyoid bone
the larynx and trachea
what are 3 areas of muscle attachment on the mandible (on the inner surface)
genial tubercles, digastric fossae, and mylohyoid line
what are 3 areas of muscle attachment on the hyoid bone
greater and lesser horns and body of hyoid bone
what are 2 palpable landmarks on the mandible
mental protuberance (chin) and the angle of the mandible
what is a palpable landmark on the base of the skull
the mastoid process
what are 2 palpable landmarks on the hyoid bone
body and greater horns
what are 3 palpable landmarks on the larynx
laryngeal prominence (adam’s apple), cricothyroid membrane, and cricoid cartilage
what can you palpate during swallowing due to the mobility of the hyoid and larynx
the laryngeal prominence
what 3 muscles are in the lateral triangle
splenius capitus, levator scapulae, scalene muscles
what 3 vessels are in the lateral triangle
subclavian artery, external jugular vein and thyrocervial trunk (transverse cervical artery, dorsal scapular and suprascapular branches)
what 3 nerves are in the lateral triangle
spinal accessory nerve (11), brachial plexus, superficial branches of cervical plexus
what type of innervation do the sternocleidomastoid (SCM) and trapezius muscles receive
general efferents from the spinal accessory nerve (11)
what does the sternocleidomastoid divide the neck into
two triangles: lateral or posterior triangle and anterior triangle
where is the lateral/posterior triangle located
posterior to SCM, anterior to the trapezius muscle and superior to the middle part of the clavicle
where is the anterior triangle located
anterior to SCM, inferior to the inferior border of the mandible and lateral to the midline of the neck
what muscles are associated with the anterior triangle
the muscles that are associated with the hyoid bone
Name 5 glands and viscera that are associated with the anterior triangle
thyroid, parathyroid, larynx, trachea and esophagus
what vessels are associated with the anterior triangle
the great vessels (internal and external jugular veins and carotid arteries)
what nerves are associated with the anterior triangle
spinal and cranial nerves
how many smaller triangles make up the anterior triangle and what are they
4: submandibular triangle, submental triangle, muscular triangle, and carotid triangle
what 2 muscles subdivide the anterior triangle into smaller triangles
the anterior belly of the omohyoid and the digastric muscle (anterior and posterior bellies)
what are the muscles in the root of the neck
sternocleidomastoid (SCM), trapezius and scalene muscles
What does the root of the neck have
structures passing between the neck, thorax, and upper limb
Besides the structures passing through the root of the neck, what else projects into it
superior parts of the lungs
what are the arteries in the root of the neck
branches of subclavian arteries (vertebral artery, inferior thyroid artery and its ascending cervical branch, and the deep cervical artery)
what are the veins in the root of the neck
tributaries to the subclavian veins (only know internal and external jugular veins)
what nerves are in the root of the neck
phrenic and vagus nerves, the cervical parts of the sympathetic chains and the brachial plexus
where is the thoracic duct in the root of the neck
(major lymph channel from the abdomen)- passes through the root of the neck from the thorax on its way to the junction between left internal jugular vein and the left subclavian vein
what are the 2 types of muscles in the neck
suprahyoid and infrahyoid (strap) muscles
where are the 4 suprahyoid muscles located
in the submental and submandibular triangles
where are the 4 infrahyoid (strap) muscles located
in the muscular triangles
what action do the suprahyoid muscles do
raise the hyoid bone or depress the mandible
what action do the infrahyoid (strap) muscles do
depress hyoid bone
what innervates the suprahyoid muscles
nerve to mylohyoid (V3) and facial nerve
what innervates the infrahyoid (strap) muscles
ansa cervicalis (cervical plexus) except thyrohyoid muscle (nerve to thyrohyoid)
what are the 4 suprahyoid muscles
digastric- anterior and posterior belly, stylohyoid and mylohyoid muscles
what are the 4 infrahyoid (strap) muscles
omohyoid, sternohyoid, sternothyroid, and thryohyoid
where is the mylohyoid muscle
forms the floor of the mouth
what innervates the anterior belly of the digastric muscle and the mylohoid muscle
general efferents from the mandibular nerve (V3) via nerve to mylohyoid
what innervates the posterior belly of the digastric and the stylohyoid muscles
general efferents from the facial nerve
what triangle is the superior belly of the omohyoid muscle in
the anterior triangle
what triangle is the inferior belly of the omohyoid muscle in
the lateral triangle
what are the thyrohyoid and sternothyroid muscles deep to
the superior belly of the omohyoid muscle and the sternohyoid muscle
what innervates the thyrohyoid muscles
general efferents from C1 that hitchhike on the hypoglossal nerve (12)
where is the cervical plexus located
ventral rami of C1-4 (mainly C2-4)
what are the 4 parts of the cervical plexus (superficial to deep)
cutaneous branches, ansa cervicalis, deep muscular branches, and phrenic nerve
where is the cutaneous branch located
C2-4
where is the ansa cervicalis located
C1-3 (GE branches go to infrahyoid strap muscles)
where is the deep muscular branch located
C1-4, general efferents to deep neck muscles
where is the phrenic nerve located
C3-5 (overlaps the brachial plexus)
what does the cutaneous branch of the cervical plexus carry
general afferents from the skin of the neck
what does the deep muscular branch of the cervical plexus carry
innervate the deep cervical muscles including the rectus capitis anterior, rectus capitis lateralis, longus colli and longus capitis muscles
what does the phrenic nerve of the cervical plexus carry
innervates the diaphragm
where does the vagus nerve exit the cranial cavity
through the jugular foramen between glossopharyngeal (9) and accessory (11) nerves
where does the vagus nerve go once it has exited the cranial cavity
enters the carotid sheath and descends through the neck behind the internal jugular vein and the internal carotid and common carotid arteries
what are the 3 branches off the vagus nerve that monitor partial pressures of oxygen in the blood
pharyngeal, laryngreal, and cardiac
what are the 4 cutaneous branches of the cervical plexus (superficial nerves)
transverse cervical nerves (C2-3), supraclavicular nerves (C3-4), great auricular nerves (C2-3), and lesser occipital nerves (C2-3)
where is the superior root of the ansa cervicalis
branches from C1 travel with the hypoglossal nerve (12) and then descend to meet the inferior root on the anterior surface of the carotid sheath
where is the inferior root of the ansa cervicalis
C2-3, descends either medial or lateral to internal jugular vein before turning medially to join the superior root
where does the hypoglossal nerve (12) leave the cranial cavity
through the hypoglossal canal- medial to the internal carotid, passes between internal jugular vein and internal carotid artery
where does the spinal accessory nerve (11) leave the cranial cavity
jugular foramen and supplies general efferents to the SCM and trapezius muscles
what rami does the superior cervical ganglion pass through
C1-4
what rami does the middle cervical ganglion pass through
C5-6
what rami does the inferior cervical ganglion pass through
C7-8
where does the motor component of the Trigeminal nerve (V3) go to
the mylohyoid muscles
what are the 2 direct branches of the subclavian arteries
vertebral arteries, branches of thyrocervical trunk (inferior thyroid artery -> ascending cervical artery), and branches of the costocervical trunk (deep cervical artery)
where does the common carotid divide into internal and external branches
near the hyoid bone
what is the carotid sinus
near the bifurcation: the common carotid artery and the beginning of the internal carotid artery are dilated
what does the carotid sinus contain
barorescptors that monitor changes in blood pressure
Where is the carotid body and what does it do
near the carotid sinus, contains chemorescptors that monitor the partial pressure of oxygen and CO2 in the body
what is carotid artery stenosis
narrowing of the common, internal or external carotid arteries
what are 3 causes of a carotid artery stenosis
coronary artery disease, peripheral arterial stenosis, and hypertension
what are 3 symptoms of carotid artery stenosis
TIA, artery bruits, and tinnitis
what are 4 treatments for carotid artery stenosis
drugs, reduction of risk factors, endarterectomy, and stents
what are 3 complications of carotid artery stenosis
stroke, myocardial infarction, and death
is the plaque stable in carotid artery stenosis
yes and it will be asymptomatic or it can embolize and send small pieces to the brain
what are the 3 pulse points in the neck region
external carotid artery, superficial temporal artery, and facial artery
what forms the tributary of the external jugular vein
the union of the posterior auricular vein and the posterior division of the retromandibular vein
what are the 6 tributaries of the internal jugular vein
common facial vein, superior thyroid vein, middle thyroid vein, lingual vein, pharyngeal plexus, and occipital veins
what is the tributaries of the brachiocephalic veins
inferior thyroid vein
what are the 2 tributaries of the external jugular vein
anterior jugular vein and indirectly the communicating vein (facial and anterior division of retromandibular)
what type of gland is the thyroid gland
endocrine (ductless, hormone-secreting) *largest endocrine gland in body
where is the thyroid gland
deep to sternothyroid and sternohyoid muscles from C5-T1
what does the thyroid gland secrete
thyroxine (for regulation of metabolism by converting iodine)
what are the 4 parts of the thyroid gland
2 lateral lobes, connected by Isthmus and a pyramidal lobe
what surrounds the thyroid gland
a tough, fibrous sheath
where does the thyroid develop from
from the floor of the pharynx at the base of the tongue at the foramen cecum
what are parathyroid glands
endocrine glands on the posterior surface of the thyroid
how many parathyroid glands are ther
usually 2 superior and 2 inferior
what do the parathyroid glands secrete
parathyroid hormone involved in calcium metabolism
what is the blood supply to the thyroid and parathyroid glands
external carotid -> superior thyroid artery
thyrocervical trunk -> inferior thyroid artery
what are the veins that drain the thyroid and the parathyroid
superior and middle thyroid veins -> internal jugular vein
inferior thyroid vein -> brachiocephalic vein
what does 10% of the population have in addition to the normal blood supply to the thyroid
thyroid ima artery (may arise from brachiocephalic trunk, aorta, right common carotid, subclavian or internal thoracic artery)
what is the innervation to the thyroid and parathyroid glands
visceral efferents only from sympathetics: from superior, middle, and inferior cervical ganglia (constrict the blood vessels)
what regulates the secretions of the thyroid and parathyroid glands
pituitary glands
what is a thyroglossal duct cyst
the duct usually disappears early in development but remnants may persist as a cyst- usually excised with central part of hyoid bone
what is a goiter
diffuse, irregular enlargement of the thyroid gland not related to neoplasm or swelling
what causes a goiter
iodine insufficiency
what can a goiter compess
trachea, esophagus, and recurrent laryngeal nerves
what are 3 complications of thyroid surgery
post-op bleeding, damage to recurrent or external laryngeal nerves, and inadvertent removal of parathyroids
what symptoms occur with damage to the recurrent or external laryngeal nerves
unilateral = hoarseness after surgery, bilateral= aphonia and/or laryngeal spasm
what is tetany
severe convulsions: results if the parathyroid glands are removed and there is a decline in calcium levels
