Anterior Neck Flashcards
Lecture 1
boundaries of the neck
anterior to lower mandible to upper surface of manubrium
posteriorly to superior nuchal line of occipital bone and intervertebral disk between C7-T1
four neck compartments
visceral
vertebral
2 vascular
visceral compartment
contents?
digestive and respiratory components, + endocrine
vertebral compartment
largest, brachial and cervical plexuses
cervical vertebrae, spinal cord, cervical nerves and muscles
vascular compartments contents
major blood vessels and vagus nerve
fascia of the neck compartments
vertebral - pre vertebral fascia
vascular: carotid sheath fascia
visceral: pre tracheal fascia
deep/investing fascia
surrounds all compartments of the neck
forms small compartments for each muscle by splittingsuper
superficial fascia
What is contained within (muscle)?
mostly anterior, contains muscle fibers of the platysma
platysma
origin: infra and supraclavicular regions
insertion: base of mandible, skin of cheek, angle of mouth
action: draw lateral angle of lips down, protect superficial venous drainage
innervation: facial n
superficial venous drainage
What vessels? What connects them?
anterior jugular and external jugular veins
anterior drains anterior compartment of neck
external drains blood from neck and skull
connected by jugular venous arch
triangles of the neck
boundaries
anterior: SCM ant border, inferior mandible to manubrium
posterior: posterior SCM, ant trapezius, distal 1/3 clavicle
triangles of anterior triangle
submental, submandibular, muscular, carotid
submental triangle
boundaries
smallest
hyoid to anterior digastric
submandibular triangle
boundaries
sub mandible to digastric
carotid triangle
boundaries
largest
SCM ant, digastric, omohyoid
muscular triangle
boundaries?
hyoid, superior omohyoid, anterior SCM
content of submandibular triangle
facial a/v, submandibular gland, hypoglossal n
content of submental triangle
submental lymph nodes
content of carotid triangle
int jugular, carotid a, vagus, ansa cervicalis
content of muscular triangle
thyroid and parathyroid glands
muscles of anterior triangle
suprahyoid muscles:
stylohyoid, digastric, mylohyoid, geniohyoid
infrahyoid muscles: sternohyoid, omohyoid, thyrohyoid, sternothyroid
stylohyoid
origin: base of styloid process
insertion: greater horn
action: pull hyoid post/superior in swallow
innervation: facial n
stylohyoid ligament
function?
improve mechanical efficiency of stylohyoid muscle by stabilizing
digastric
origin: ant - digastric fossa; post - mastoid process
insertion: tendon between 2 bellies, body of hyoid
action: elevate hyoid, depress mandible
innervation: mylohyoid n
mylohyoid
origin: mylohyoid line on mandible
insertion: hyoid body
action: support, elevate floor of mouth, elevate hyoid
innervation: mylohyoid n
geniohyoid
origin: inferior mental spine
insertion: hyoid body
action: fixation of mandible, pull mandible in
innervation: anterior ramus C1
sternohyoid
origin: post aspect sternoclavicular ligament
insertion: hyoid body
action: depress hyoid after swallowing
innervation: ansa cervicalis
omohyoid
origin: superior border of scapula
insertion: hyoid body
action: depress hyoid
innervation: anterior rami C1-C3
thyrohyoid
origin: thyroid cartilage
insertion: greater horn hyoid
action: depress hyoid, elevate thyroid cartilage
innervation: anterior ramus C1
sternothyroid
origin: manubrium
insertion: thyroid cartilage
action: draw larynx/thyroid cartilage down
innervation: ansa cervicalis
common carotid
Where does it come from, what does it split in to?
rise into the neck
on the left this is a branch of the aortic arch, on the right it branches from the brachiocephalic trunk
at C3 this artery bifurcates into external and internal carotid
internal carotid artery
supplies all structures within the skull
external carotid artery
supplies what?
supplies all structures outside the skull
internal jugular vein
What drains into it? Where does it drain?
receives blood from all structures in the head and neck, drains into the subclavian vein
which vein in the neck is used for central venous access or a ventral venus catheter?
internal jugular
previously subclavian which overlaps apex of the lungs
which nerves of the anterior triangle pass through the jugular foramen?
CN 9 - glossopharyngeal
CN 10 - vagus
CN 11 - Accessory
Which anterior triangle nerve passes through the hypoglossal canal?
CN 12 - hypoglossal
functions of CN 9
innervate pharyngeal wall
mixed nerve
functions of CN 10
innervate larynx, lungs, heart, liver, and abdominal structures
mixed nerve
functions of CN 11
innervate SCM and trapezius
motor nerve
functions of CN12
innervate tongue
motor nerve
ansa cervicalis
roots? What does it innervate?
loop of nerves C1-C3
innervates the infrahyoid mm.
has superior and inferior roots
prevertebral mm
list muscles, action
rectus capitis anterior, rectus capitis lateralis, longus capitis, longus colli
don’t need specific OIAs but know general posiitons for clinical significance
all perform neck flexion and are very small, connected to vertebral bodies and occipital bone
