Ant/Post triangles Flashcards
What are the borders of the posterior triangle of the neck
roof: investing fascia
anterior: SCM
posterior: trapezius
inferior: clavicle
floor: pre-vertebral fascia covering scalenes and other mm
what divides the post triangle into 2
inferior belly omohyoid
what are the 2 triangles in post triangle
superior: occiptal
inferior: omoclavicular
what run within post triangle
ext jugular, cutaneous nn, CN XI, brachial plexus, inf belly omohyoid, subclavia, transverse cervical a and tributaries, deep cervical lymph nodes
what plexus does the spinal accessory n join with
subtrapezial with branches of ventral rami C3 C4
where doesn brachial plexus run in post triangle
between ant and middle scalenes
what causes throacic outlet syndrome
compression of brachial plexus, hypertrophy of scalenes
what is the axillary sheath an extension of
prevertebral fascia
what are the branches of the brachial plexus in neck
dorsal scap, accessory phrenic, nerve to subclavius, suprascapular, long thoracic n
which scalene does dorsal scap n pass through and what cervical levels contribute
pass through middle scalene
C5
where does accessory phrenic travel and what cord level is it
C5 descends parallel to phrenic n on lateral surface of anterior scalene
what cord levels give rise to nerve to subclavius and where does it run
C5C6
anterior to brachial plexus and the subclavian vessels and posterior to clavicle
what cord levels give rise to suprascap n and where does it course
C5C6
parallels suprascapular vessels to an area of scapular notch to inn supra and infra spinatus
what cord levels give rise to long thoracic n and where does it run
C5C6C7
descend into axilla on lateral surface os serratus anterior muscle
what cord levels contribute to the direct inn of scalene mm
C5-C8
where does occiptal a branch from
external carotid
what n does occipital a run with
occiptal n
where do the transverse cervical and suprascapular aa branch from
thyrocervical trunk from subclavian a
what a runs in the axillary sheath with brachial plexus
subclavian a
what are the branches off subclavian in neck area
transverse cervical
suprascapular
dorsal a
describe the nodes found in deep cervical system
accessory nodes run with spinal accessory
transverse cervical nodes run with transverse cervical a
where do the accessory nodes receive lymph from
occipital nodes and retroauricular nodes
where do the transverse cervical nodes receive lymph from
accessory chain of nodes, lateral neck, post thorax, upper ant thoracic wall
describe the boundaries of the anterior triangle
roof: investing fascia
anterior: line from symphasis menti to sternal notch
posterior: SCM
superior: inferior margin mandible
floor: structural componenets
What are the 2 groups of mm in atnerior triangle
suprahyoid and infrahyoids
what are the suprahyoid mm
digastric, stylohyoid and myohyoid
origin and insertion of digastric m
o: anterior belly- digastric fossa of mandible
posterior belly- mastoid notch of temporal bone
i: hyoid bone via fascial sling from intermediate tendon
what are the actions of digastric and inn
elevates hyoid and base of tongue, assists in opening mouth
ant belly- mylohyoid N (V3)
post belly- digastric branch of VII
what are the o and in of stylohyoid
o- post base of styloid process
i- body of hyoid bone near lesser horn
action and inn of stylohyoid
action- elevates and retracts the hyoid and base of tongue
inn- digastric branch of facial N VII
o and in of mylohyoid
o- mylohyoid line of mandible
i- midline raphe from symphysis menti to body of hyoid bone
action and inn of mylohyoid
action- elevates hyoid and floor of mouth, depresses mandible when hyoid is fixed
inn- mylohyoid branch of V3
What are the infrahyoid mm
sternohyoid, sternothyroid, thryohyoid and omohyoid
o and i of sternohyoid
post surface of manubrium at sternoclavicular joint, clavicle and posterior sternoclavicular lig
i- inferior margin body of thyroid
o and in of sternothyroid
o- posterior surface of manubrium inferior to sternohyoid
i- oblique line of thyroid cartilage
action and inn of sternothyroid
action- depresses larynx
inn- ansa cervicalis of cervical plexus
action and inn of sternohyoid
action- depresses hyoid and larynx
inn- ansa cervicalis of cervical plexus
o and i of thryohyoid
o- oblique line of thryoid cartilage
i- inferior margin of body and greater horn of hyoid
action and inn of thyrohyoid
action- depresses hyoid and tongue when larynx is fixed from below; elevates larynx when hyoid is fixed from above
inn- C1 via hypoglossal N
o and i of omohyoid
o: superior- infeiror margin greater horn hyoid
inferior- superior margin of scapula near notch and suprascap ligament
i- fascial sling of infrahyoid fascia to clavicle and first rib
action and inn of omohyoid
action- stabilizes, retracts and depresses hyoid and larynx
inn- ansa cervicalis of cervical plexus
what type of gland is thyroid gland
endocrine
what type of cells are endocrine function in thyroid
follicular cells secrete thyroxin
parafollicular cells secrete calcitonin
what is the role of calcitonin
decrease circulating Ca
where is the thyroid gland located
posterior to sternohyoid and sternothyroid mm
what tracheal rings does the isthmus of the thyroid cross
2nd-4th
what fascia surrounds thyroid
pretracheal
what causes thyroglossal duct cysts
absent pyramidal lobe, ectopic glandular tissue can remain active and descend
What aa supply thyroid
superior thyroid and inferior thryoid a
some have thyroid ima a
where does superior thryoid a come from
external carotid a
What are the major branches of superior thyroid a
superior laryngeal, anterior branch and posterior branch
what a runs with the internal laryngeal n that pierces thyrohyoid membrane
superior laryngeal a
where does the inferior thyroid a branch from
thyrocervical trunk
where does the inferior thyroid a run
behind carotid sheath and sympathetic trunk at level of thyroid cartilage
What does the infeiror thyroid a anastomose with
post branches from superior thyroid a
what is the thyroid ima a
variable unpaired branch of brachiocephalic or from aortic arch
anastomoses with inferior thyroid aa
what is clinically important about thyroid ima a
tracheostomy must be done carefullt if patient has this a
what vv drain thryoid
superior thryoid, middle and inferior
where does the superior thyroid v drain to
internal jugular
Where does the middle thyroid v drain to
internal jugular from lateral surface gland
where does the inferior thyroid v drain to
drain thyroid gland, esophagus larynx, and trachea into R and L brachiocephalic vv
If inferior thyroid vv fuse together where do they drain
L brachiocephalic
What nodes are included in lymph drainage of thyroid
pre-laryngeal, pre-tracheal and para-tracheal and superior/inferior deep cervical
all lymph from thyroid gland eventually drains where
deep cervical nodes
what fibers inn thyroid gland
preganglionic SAN from T1-4
postganglionic SAN from superior middle and cervicothoracic ganglia via sympathetic cardiac nn, superior and infeiror laryngeal nn
What are the Parathyroid glands
2-6 small flattened bodies located beneath capsule of thyroid gland
superiorly at circoid cartilage and inferiorly at inferior pole of gland
What is secreted by parathyroid glands
PTH which helps to increase serum Ca
Inadvertent removal of parathyroid gland leads to what
tetany and death
how much of the trachea is considered the cervical portion
half
what encloses the tracheal rings posteriorly
trachealis m
what inn trachealis m
SAN from trunk
PAN from vagus and recurrent laryngeal nn
what lays posterior to trachea
esophagus and recurrent laryngeal nn
what aa and vv supply trachea
infeiror thryoid aa and vv
what is the lymph drainage of trachea
pre-tracheal, para-tracheal, inferior deep cervical
which way does the esophagus incline as it descends through neck
left
what layrs lateral to the esophagus
thyroid gland, carotid sheatha nd thoracic duct on the left
what lays posterior to the esophagus
pre-vertebral fascia over pre-vertebral mm and vertebral column
what is the aa and vv to esophagus
inferior thyroid aa and vv
lymph drainage of esophagus
paratracheal and inferior deep cervical nodes
what inn esophagus
SAN from trunk, both vasomotor and glandular
PAN recurrent laryngeal for muscular tone and glandular
