Neck: bones, fascia, posterior triangle Flashcards
3rd part of the subclavian artery lies ____ and ____ to the subclavian vein, emerging between what two muscles?
posterior and superior.
emerging between anterior and middle scalenes
3rd part of the subclavian artery: crosses over ___ ____ to become axillary, and usually gives rise to what?
crosses over 1st rib
dorsal scapular artery
the neck is relatively slender and flexible to allow for what?
efficient use of sensory organs
the hyoid bone is at what C level? what is it suspended between?
C3
Suspended between styloid process & thyroid cartilage
C__ has a carotid tubercle. while C__ has longer spinous processes that is NOT bifid (aka ____ _____)
C6
C7- vertebrae prominens
what is clinically important about facet joints of cervical vertebrae?
facet joints are zygopophysial (in transverese plane- slope inferior-laterally- (not truly horizontal) ) - permits flexion, extension, lateral flexion.
which is the widest cervical vertebrae with no body or spinous process?
C1- atlas
which cervical vertebrae? … Ring-shaped with large lateral masses (support occipital condyles of cranium). Transverse ligament between
C1- atlas
Strongest cervical vertebrae
C2- axis
which cervical vertebrae has the Dens (odontoid process)-superior projection from body?
C2- axis
vertebral arteries begin ascent at level C__
6
hyoid bone is in the angle between ____ and _____ _______.
Angle between mandible & thyroid cartilage
hyoid bone is suspended by the _____ _______. connected by muscles to what 4 things?
Suspended by stylohyoid ligament
Connected by muscles to skull, thyroid cartilage, manubrium, & pectoral girdle
the hyoid bone has what 3 parts? what is are its two purposes?
Body, lesser horns, greater horns
Adds rigidity to airway & attachments for anterior cervical muscles
what are the 4 layers of cervical fascia?
Superficial layer
3 separate deep columns: Investing, Pretracheal, Prevertebral
what are the 3 functions of cervical fascia?
Compartmentalize muscles & viscera
Conduit for neurovascular structures
Allows gliding of structures
what cervical fascia is just Deep to dermis, very thin? what two structures are within this layer?
superficial layer (aka hypodermis, aka subcutaneous)
- platysma muscle (highly variable)
- external jugular vein (anterolaterally)
what is the platsyma muscle used for? what is it innervated by?
Facial expression
Cervical branch of facial nerve (CN VII)
how wide and how thick is the platysma? where is it located?
about 1mm thick, about 1 hands width on either side.
-starts at body of mandible and fans down to clavicles. does NOT meet in the midline.
investing deep cervical fascia, splits to invest what two muscles? invests what two glands?
muscles: sternocleidomastoid & trapezius
glands: submandibular & parotid
origins, insertions and innervations of SCM and trapezius muscle ?
Nearly continuous origins at base of skull
Nearly continuous insertions to scapular spine, acromion, clavicle, & manubrium
Both muscles innervated by spinal accessory nerve (CN XI)
pretrachial deep cervical fascia invests what two types of structures? extends from _____ to ______.
Invests muscles & viscera in anterior neck
Extends from hyoid to pericardium of heart
the pretrachial deep cervical fascia forms pulleys for what two things?
Forms pulleys for intermediate tendons of digastric & omohyoid
Continuous superiorly as buccopharyngeal fascia of pharynx
muscular vs visceral portion of pretrachial deep cervical fascia? ( thin vs thick, what does each surround? )
Muscular portion-thin, surrounds infrahyoid muscles
Visceral portion-thick, surrounds thyroid, trachea, & esophagus
what fascia layer is Continuous superiorly as buccopharyngeal fascia of pharynx?
pretracheal deep cervical fascia
what is the clinical significance of the buccopharyngeal fascia?
buccopharyngeal fascia that invests posterior wall of pharynx. BEHIND that is potential space: where pharyngeal infections can rapidly spread superior or inferiorly “retropharyngeal space”
prevertebral deep cervical fascia surrounds what structures?
Surrounds vertebral column & associated muscles
the carotid sheath is formed by which layers of the cervical fascia? from where to where does it extend?
Formed from all 3 deep sheaths
Extends from cranial base to root of neck
what does the carotid sheath contain? (5)
Common, external, & internal carotids
Internal jugular
Vagus (CN X)
Nerve to carotid sinus
Carotid arterial plexuses (postganglionic sympathetic neurons)
“CN IVS”
what is the Potential space between pretracheal & prevertebral sheaths? what is this subdivided by?
retropharyngeal space- subdivided by alar fascia
retropharyngeal space: which end is opened and which is closed?
Closed at cranial base superiorly & carotid sheath laterally
Open to superior mediastinum inferiorly
retropharyngeal space- pretracheal (visceral portion) and carotid sheaths are continuous with ______superiorly and _______ inferiorly ?
with cranial cavity superiorly & mediastinum inferiorly
superficial neck is deep to what fascia(s)? superficial to what fascia(s)?
Deep to superficial fascia
Superficial to prevertebral & visceral pretracheal fascias
superficial neck: ___ regions based on ___ muscles ?
4, 2
four regions of the superficial neck
Sternocleidomastoid
Posterior
Lateral (posterior triangle)
Anterior (anterior triangle)
SCM: O, I, A, In
O-mastoid process
I-manubrium (sternal head); medial 1/3 of clavicle (clavicular head)
A- Extension of head, flexion of cervical spine, laterally flexes (ipsi) & rotates head (contra)
In- Spinal accessory nerve (CN XI)
what fossa is between the heads of the SCM? what structure is within here?
lesser superclavicular fossa - inferior IJV
the internal jugular vein is near the (superior/inferior) 1/2 of SCM while the external jugular vein is near the (superior/inferior) 1/2.
internal JV- inferior SCM
external JV - superior SCM
what two nerves cross the SCM?
greater auricular
transverse cervical
(both C2 and C3)
cervical portion trapezius: O, I, A, In
O-superior nuchal line, nuchal ligament, spinous processes C7-T12
I-lateral third of clavicle, acromion, spine of scapula
A- Superior fibers elevate scapula
In -Spinal accessory nerve (CN XI)
dorsal rami of cervical spinal nerves supply what type of innervation?
cutaneous innervation
C2 (Greater occipital)
C3 (Least occipital)
C4
what are the borders of the posterior triangle?
Anterior-posterior border of SCM
Posterior-anterior border of trapezius
Inferior-middle third of clavicle
Superior-union of SCM & trapezius at mastoid process
what makes up the floor of the posterior triangle?
Floor-prevertebral fascia & muscles:
- Middle & posterior scalene
- Levator scapulae
- Splenius capitis
Inferior belly of omohyoid divides posterior triangle into what two triangles?
occipital & omoclavicular (subclavian) triangles
what artery is a Branch of external carotid at the
Apex of occipital triangle?
occipital artery
what arteries are branches of thyrocervical trunk at the Base of occipital triangle?
suprascapular artery
and transverse cervical artery
suprascapular artery is superficial to what nerve(s)? and supplies what muscles?
Superficial to phrenic nerve & trunks of brachial plexus
Supplies muscles of posterior shoulder (“army over”)
what two arteries are superficial to phrenic nerve and trunks of brachial plexus?
suprascapular artery and trans. cervical artery
transverse cervical artery may divide into what two branches? what does each supply?
May divide into superficial & deep (dorsal scapular) branches
Superficial-trapezius
Dorsal scapular-levator scapulae, rhomboids, scapula
the external jugular vein is formed by the merging of what two veins (superiorly)? where does it enter the occipital triangle? what does it empty into?
Merging of retromandibular & posterior auricular
Enters occipital triangle at posterior border of SCM
Empties into subclavian vein
the subclavian vein is a continuation of what? what triangle does it cross?
Continuation of axillary vein
Crosses omoclavicular triangle anterior to anterior scalene
primary loops of the cervical plexus form between what?
Primary loops form between adjacent ventral rami
C1-C2, C2-C3, C3-C4, C4-C5
branches emerging from the loops: sensory course _____ while motor course ____.
sensory: posteriorly
motor: anteriorly
what forms the superior and inferior roots of ansa cervicalis?
superior: C1 only (motor from C1-C2 loop)
inferior: C2 & C3 (motor)
the motor branch of C1-C2 loop runs with what nerve initially?
hypoglossal (CN XII)
Nerves to ________ & _____leave hypoglossal separate from superior root ( C_ fibers only)
Nerves to thyrohyoid & geniohyoid leave hypoglossal separate from superior root
C1 fibers only
the inferior root of ansa cervicalis supplies what muscles?
Supply 3/4 infrahyoid muscles
Omohyoid
Sternohyoid
Sternothyroid
C2-C3 loop: sensory- what are the three branches?
lesser occipital, greater auricular, transverse cervical
lesser occipital nerve: what does it course along? what does it supply?
Parallels posterior SCM
Supplies posterolateral neck & scalp
greater auricular nerve: what does it course along? what does it supply?
Courses with EJV
Supplies posterior auricle & parotid region (between mastoid process & angle of mandible)
transverse cervical nerve: what does it cross? what does it supply?
Crosses SCM
Supplies anterior cervical region
C3-C4 loop: sensory - what is the branch? what does it supply?
Supraclavicular
Supplies clavicular skin & shoulder
C3-C4 loop: motor- what is the branch? what does it supply?
phrenic (Contribution from C5)
Motor to diaphragm
Visceral afferents from pericardium, pleura, etc.
C4-C5 loop: contributes motor fibers what two nerves of the brachial plexus?
motor fibers to dorsal scapular (C4, C5) & long thoracic (C5) nerves of brachial plexus
spinal accessory nerve (CN XI): enters occipital triangle where? what does it supply?
Enters occipital triangle at mid-SCM
Crosses triangle inferolaterally
Innervates SCM & trapezius
Only motor nerve superficial to prevertebral fascia
spinal accessory CN XI
posterior (cutaneous) branches of cervical plexus (C1-C4) emerge where in relation to the SCM?
at posterior midpoint of SCM
what are the 4 posterior (cutaneous) branches of the cervical plexus ?
Lesser occipital
Great auricular
Transverse cervical
Supraclavicular
roots/trunks of brachial plexus emerge between what two muscles? descend ______ to enter the axilla. what is this called?
Emerge between anterior & middle scalenes
Descend inferolaterally to enter axilla
“Cervico-axillary canal”
suprascapular nerve is a branch of ____ trunk of the brachial plexus. where does it cross? what does it supply?
superior trunk
Crosses occipital triangle laterally
Innervates muscles of posterior scapula (“navy under”)
