Posterior Triangle & Root of the Neck Flashcards
Hyoid bone
unpaired bone, located inferior to inferior aspect of the mandible
single bone with a central body and greater horns/cornua on each side
lies in anterior neck at the level cv3
-does not articulate with any other bone
-larynx suspended here from thyrohyoid membrane
unpaired bone, located inferior to inferior aspect of the mandible
single bone with a central body and greater horns/cornua on each side
lies in anterior neck at the level cv3
-does not articulate with any other bone
-larynx suspended here from thyrohyoid membrane
hyoid bone
name the structures in the neck found at Cv6
junction of pharynx and esophagus
middle cervical sympathetic ganglion
vertebral artery enters the first transverse foramen
the posterior triangle is covered by which dermatomes
c2, c3, c4
what are the nerves that make up the cutaneous component of the cervical plexus?
lesser occipital nerve - c2
great auricular nerve - C2 C3
transverse cervical nerve - C2, C3
supraclavicular nerves - C3, C4
what are the boundaries of the posterior triangle?
anterior= posterior border of the sternocleidomastoid muscle posterior = anterior border of the trapezius inferior = clavicle
what are the muscles of the floor of the posterior triangle?
they are covered by which fascia?
splenius capitis splenius cervicis levator scapulae posterior scalene middle scalene anterior scalene
prevertebral fascia
which components are found between the prevertebral layers of deep fascia and investing layers of fascia in the posterior triangle?
spinal accessory nerve
inferior belly of the omohyoid muscle
transverse cervical vessels
cutaneous nerves to the skin
which components are found between the prevertebral layers of deep fascia and the floor of the posterior triangle?
dorsal scapular nerve long thoracic nerve phrenic nerve proximal portion of the brachial plexus third part of the subclavian artery
where are these structures located?
dorsal scapular nerve long thoracic nerve phrenic nerve proximal portion of the brachial plexus third part of the subclavian artery
between the prevertebral layers of deep fascia and the floor of the posterior triangle
where are these structures located?
spinal accessory nerve
inferior belly of the omohyoid muscle
transverse cervical vessels
cutaneous nerves to the skin
between the prevertebral layers of deep fascia and the investing layers of the posterior triangle
sternocleidomastoid muscle =
anterior border of the posterior triangle
origin = the manubrium and the medial end of the clavicle
insertion = mastoid process
innervation = accessory nerve (motor) and branches of C2 and C3 (sensory)
action = 1 side contracts - turns head to opposite side, 2 sides contract - flexion of the neck
*accessory muscle of respiration - shows in signs of respiratory distress
anterior border of the posterior triangle
origin = the manubrium and the medial end of the clavicle
insertion = mastoid process
innervation = accessory nerve (motor) and branches of C2 and C3 (sensory)
action = 1 side contracts - turns head to opposite side, 2 sides contract - flexion of the neck
*accessory muscle of respiration - shows in signs of respiratory distress
sternocleidomastoid
lie on the floor of lateral neck covered by cervical fascia
3 groups
all originate from anterior or posterior tubercle of transverse processes
innervated by cervical nerves
action = muscles acting together are muscles of inspirations, also act on vertebral column of neck
scalene muscles
anterior scalene (scalenus anterior)
landmark muscle in floor of the neck
origin = anterior tubercle of transverse process of Cv3-Cv6 insertion = scalene tubercle of the first rib between the grooves for subclavian vessels innervation = C5-c7
phrenic nerve crosses anterior to this muscle
landmark muscle in floor of the neck
origin = anterior tubercle of transverse process of Cv3-Cv6 insertion = scalene tubercle of the first rib between the grooves for subclavian vessels innervation = C5-c7
phrenic nerve crosses anterior to this muscle
anteior scalene
middle scalene
largest of this group of muscles
origin = posterior tubercle of the transverse processes of Cv3-cv7 insertion = scalene tubercle of the first rib immediately posterior to the brachial plexus and subclavian artery innervation = C2-C8
largest of this group of muscles
origin = posterior tubercle of the transverse processes of Cv3-cv7 insertion = scalene tubercle of the first rib immediately posterior to the brachial plexus and subclavian artery innervation = C2-C8
middle scalene
posterior scalene
smallest and most posterior of this group
origin = posterior tubercle of the transverse processes of Cv5-Cv7 insertion = second rib innervation = Cv7-Cv8
smallest and most posterior of this group
origin = posterior tubercle of the transverse processes of Cv5-Cv7 insertion = second rib innervation = Cv7-Cv8
posterior scalene
omohyoid muscle
one of the infrahyoid muscles
2 bellies connected by a tendon
inferior belly is in the posterior triangle
origin = upper border of the scapula insertion = lower border of the hyoid bone innervation = ansa cervicalis
one of the infrahyoid muscles
2 bellies connected by a tendon
inferior belly is in the posterior triangle
origin = upper border of the scapula insertion = lower border of the hyoid bone innervation = ansa cervicalis
omohyoid muscle
which structures are found between the anterior scalene and middle scalene muscle?
subclavian artery
anterior/ventral primary rami (forming the brachial plexus)
where do these structures pass in the posterior triangle?
subclavian artery
anterior/ventral primary rami
between the anterior and middle scalene muscles
which structures lie superficial to the scalenus anterior muscle?
prevertebral fascia subclavian vein phrenic nerve transverse cervical artery suprascapular artery omohyoid muscle
where do these structures pass in the posterior triangle?
prevertebral fascia subclavian vein phrenic nerve transverse cervical artery suprascapular artery omohyoid muscle
anterior to the scalenus anterior muscle
name the structures immediately above the first rib from anterior to posterior
subclavian vein anterior scalene subclavian artery lower portion of brachial plexus middle scalene
where is the brachial plexus in the posterior triangle?
between the middle and anterior scalene muscles
where are these structures found?
subclavian vein anterior scalene subclavian artery lower portion of brachial plexus middle scalene
immediately above the first rib in the posterior triangle
where is the sternoclavicular joint
at the root of the neck
between the medial end of the clavical and the manubrium
describe the sternoclavicular joint
an articular disk divides the joint cavity into two separate spaces
ligaments of the joint include
-articular capsule
-interior and posterior sternoclavicular ligaments
-interclavicular ligament
-costoclavicular ligament
what does the subclavian artery branch into?
vertebral artery internal thoracic artery thyrocervical trunk costocervical trunk dorsal scapular artery
(VIT. C and D)
where do these branches come from?
vertebral artery internal thoracic artery thyrocervical trunk costocervical trunk dorsal scapular artery
subclavian artery
what does the thryocervical trunk branch into?
inferior thyroid artery
suprascapular artery
transverse cervical artery
where do these branches come from?
inferior thyroid artery
suprascapular artery
transverse cervical artery
thyrocervical trunk
where does the inferior thyroid artery come from and branch into?
comes from the thyrocervical trunk from the subclavian artery
branches into the ascending cervical artery and the inferior laryngeal artery
what artery is this?
comes from the thyrocervical trunk from the subclavian artery
branches into the ascending cervical artery and the inferior laryngeal artery
inferior thyroid artery
where does the transverse cervical artery come from and branch into
comes from the thyrocervical trunk
branches into a superficial branch and a deep branch
what artery is this?
comes from the thyrocervical trunk
branches into a superficial branch and a deep branch
transverse cervical artery
where does the dorsal scapular artery come from?
can either branch off of the thyrocervical trunk (deep branch of the transverse cervical artery) or directly from the subclavian artery
what does the costocervical trunk branch into?
deep cervical artery
highest intercostal artery
where does the internal thoracic artery travel and supply?
arises from the antero-inferior aspect of the subclavian artery
descends posterior to the sternal end of the clavical to enter the thorax
travels down the middle
where does the vertebral artery travel and supply
arises from the postero-superior aspect of the subclavian artery
enters the transverse foramen of CV6
ascends up the transverse foramina until it lies on the superior aspect of the atlas
enters the suboccipital triangle to supply the brain/brainstem
arises from the antero-inferior aspect of the subclavian artery
descends posterior to the sternal end of the clavical to enter the thorax
travels down the middle
internal thoracic artery
arises from the postero-superior aspect of the subclavian artery
enters the transverse foramen of CV6
ascends up the transverse foramina until it lies on the superior aspect of the atlas
enters the suboccipital triangle to supply the brain/brainstem
vertebral artery
where does the thyrocervical trunk arise?
short trunk from the superior aspect of the subclavian artery
which artery is this?
short trunk from the superior aspect of the subclavian artery
thyrocervical trunk
where does the inferior thyroid artery arise?
branch of the thryocervical trunk
passes superiorly along the medial border of the scalenus anterior to about Cv6, where it runs medially and branches
branch of the thryocervical trunk
passes superiorly along the medial border of the scalenus anterior to about Cv6, where it runs medially and branches
inferior thyroid artery
where does the ascending cervical artery arise?
branch from the inferior thyroid artery
runs along the anterior surface of the scalenus anterior
runs with the phrenic nerve
branch from the inferior thyroid artery
runs along the anterior surface of the scalenus anterior
runs with the phrenic nerve
ascending cervical artery
where does the inferior laryngeal artery arise?
branch of the inferior thyroid artery
accompanies the recurrent/inferior laryngeal nerve
branch of the inferior thyroid artery
accompanies the recurrent/inferior laryngeal nerve
inferior laryngeal artery
where does the suprascapular artery travel?
branch of the inferior thyroid artery
passes anterior to the scalenus anterior, behind the sternocleidomastoid muscle
travels behind the clavicle to reach the region of the scapular notch
branch of the inferior thyroid artery
passes anterior to the scalenus anterior, behind the sternocleidomastoid muscle
travels behind the clavicle to reach the region of the scapular notch
suprascapular artery
where does the transverse cervical artery arise?
branch of the thryoclavicular trunk
passes between the scalenus anterior and the sternocleidomastoid muscle
turns posteriorly, crosses the posterior triangle
branches into superficial and deep branches (variant= deep branch is dorsal scapular artery)
branch of the thryoclavicular trunk
passes between the scalenus anterior and the sternocleidomastoid muscle
turns posteriorly, crosses the posterior triangle
branches into superficial and deep branches (variant= deep branch is dorsal scapular artery)
transverse cervical artery
the superficial branch of the transverse cervical artery off the thyrocervical branch travels with what nerve and where?
accessory nerve
deep surface of the trapezius muscle
the deep branch of the transverse cervical artery off the thyrocervical branch travels with what nerve and where?
dorsal scapular nerve
deep surface of the levator scapulae and rhomboid muscles
what is the variation that can occur relating to the superficial branch of the transverse cervical artery?
it may arise from the thyrocervical trunk directly as the superficial cervical artery
where does the costocervical trunk arise from?
arises from the posterior aspect of the subclavian artery
quickly divides into deep cervical artery and highest intercostal artery
arises from the posterior aspect of the subclavian artery
quickly divides into deep cervical artery and highest intercostal artery
costocervical trunk
where does the deep cervical artery come from and what does it supply?
comes from the costocervical trunk from the subclavian artery
supplies the deep muscles on the back of the neck
what artery is this?
comes from the costocervical trunk from the subclavian artery
supplies the deep muscles on the back of the neck
deep cervical artery
where does the highest/supreme/superior intercostal artery come from and what does it supply?
comes from the costocervical trunk from the subclavian artery
supplies the first two intercostal space (first posterior intercostal artery, second posterior intercostal artery
comes from the costocervical trunk from the subclavian artery
supplies the first two intercostal space (first posterior intercostal artery, second posterior intercostal artery
highest intercostal artery
platysma muscle =
very superficial, very thin
muscle of fascial expression
origin = fascia in the thoracic region insertion = inferior aspect of the mandible innervation = cranial nerve VII
muscle of fascial expression
origin = fascia in the thoracic region insertion = inferior aspect of the mandible innervation = cranial nerve VII
platysma muscle
which nerves make up the cutaneous components of the cervical plexus?
lesser occipital nerve (C2)
great auricular nerve (C2, C3)
transverse cervical nerve (C2, C3)
suprascapular nerve (C3, C4)
lesser occipital nerve
fibers from which root?
travels where?
innervates what structures?
fibers from C2
travels along the posterior border of the sternocleidomastoid muscle superiorly to the head from the nerve point on the neck (“goes up and back”)
innervates the skin of the neck and scalp posterosuperiorly to the auricle of the ear
great auricular nerve
fibers from which root?
travels where?
innervates what structures?
fibers from C2, C3
travels vertically on the surface of the sternocleidomastoid muscle (“goes north”)
innervates skin of the parotid region and auricle, supplies the skin of the angle of the mandible and continues to the mastoid process
transverse cervical nerves
fibers from which root?
travels where?
innervates what structures?
fibers from C2, C3
crosses the sternocleidomastoid muscle horizontally toward medial portion of throat
joins the cervical branch of the facial nerve inferior to the parotid gland
innervates the skin of the anterior triangle of the neck
supraclavicular nerves
fibers from which root?
travels where?
innervates what structures?
fibers from C3, C4
crosses the clavicle (“goes south”)
supplies the skin of the inferior half of the posterior triangle of the neck
supplies the skin of the upper thoracic region and deltoid regions
fibers from C2
travels along the posterior border of the sternocleidomastoid muscle superiorly to the head from the nerve point on the neck (“goes up and back”)
innervates the skin of the neck and scalp posterosuperiorly to the auricle of the ear
lesser occipital nerve
fibers from C2, C3
travels vertically on the surface of the sternocleidomastoid muscle (“goes north”)
innervates skin of the parotid region and auricle, supplies the skin of the angle of the mandible and continues to the mastoid process
great auricular nerve
fibers from C2, C3
crosses the sternocleidomastoid muscle horizontally toward medial portion of throat
joins the cervical branch of the facial nerve inferior to the parotid gland
innervates the skin of the anterior triangle of the neck
transverse cervical nerves
fibers from C3, C4
crosses the clavicle (“goes south”)
supplies the skin of the inferior half of the posterior triangle of the neck
supplies the skin of the upper thoracic region and deltoid regions
supraclavicular nerves
cranial nerve VII innervates what structure?
platysma
spinal accessory nerve (CN XII) innervates which two muscles
trapezius, sternocleidomastoid
