Neck: root of the neck Flashcards
boundaries of thoracic inlet?
posterior: body of T1, head and neck of first rib
lateral: body of first rib
anterior: distal portion of first rib
anterior scalene
O: transverse processes of Cv3-6
I: 1st rib
A: elevates first rib, side bends and rotates cervical column to opposite side. both sides acting flexes vertebral column
N: ventral rami of cervical nn.
middle scalene m.
o: transverse processes of CV2-7
I: 1st rib
A: elevates first rib, side bends and rotates cervical column, both sides acting flexes column
N: ventral rami of cervical nn.
thoracic outlet syndrome
brachial plexus and subclavian a. pass between the anterior and middle scalene muscles at “scalene triangle”
- compression by the scalene muscles undergoing tonic contraction causes pain, numbness and tingling in neck, medial 4th/5th fingers, paresis of intrinsic muscles of hand and poor circulation
posterior scalene
O: transverse processes of CV5-7
I: outer surface of 2nd rib
A: elevates second rib, side bends and rotates cervical column - both sides acting flexes vertebral column
n: ventral rami from brachial plexus C7-8
- note: often times this muscle is fused with the middle scalene *
longus capitis
O: anterior tubercles of transverse processes VC3-6
I: occipital bone
A: flexes head and neck
N: ventral rami of spinal nn C1-4
Longus Colli
O & I: upperio portion: from anterior surface of vertebral body above to transverse process of vertebrae below
lower portion: extends from anterior surface of vertebral bodies to transverse processes of vertebrae above
A: flexes neck and assists in its rotation (upper fibers rotate to same side while lower fibers rotate to side opposite)
n: ventral rami of cervical spinal nn.
where do common carotids originate?
right common carotid splits from brachiocelphalic trunk, posterior to sternoclavicular joint, into right subclavian and common carotid
left common carotid comes directly from arch of aorta
subclavian a.
courses over the cupola of lung to lateral border of 1st rib
- divided into three parts by anterior scalene muscles:
Part 1: medial to anterior scalene
Part 2: behind anterior scalene
Part 3: lateral to anterior scalene
branches of Part I of subclavian a
Part 1: medial to anterior scalene
- vertebral a.
- thyrocervical trunk: inferior thyroid, transverse cervical a, suprascapular, ascending cervical a.
- internal thoracic. a.
Part II branches of subclavian a.
underneath anterior scalene m.
- costocervical trunk: gives deep cervical a. and highest posterior intercosta a.
Part III branches of subclavian.
lateral to anterior scalene m.
- gives dorsal scapular artery
branches superiorly and ascends between longus colli and anterior scalene muscle to enter the transverse cervical foramen of CV6, ascends through cervical vertebrae and up through to foramen magum. supplies muscular branches and spinal branches of vertebrae and spinal cord and anastomoses with ascending cervical.
vertebral artery
first branch off of subclavian artery, Part I
arises from anterior-superior surface of subclavian a. medial to anterior scalene and opposite internal thoracic artery
thyrocervical trunk: provides -
inferior thyroid a. transverse cervical a. suprascapular a. ascending cervical a.
branch from thyrocervical trunk medial to acend the medial border of anterior scalene
Inferior thyroid a.
- passes BEHIND the carotid sheath and symp. trunk at level of thyroid cartilage
- provides branches to pharynx, larynx, trachea and esophagus before going to inferior thyroid.
- anastomoses with posterior branches of superior thyroid a.
- brahcnes from thyrocervical trunk laterally
- crosses posterior triangle inferiorly, medial to inferior belly of omohyoid m.
- exits posterior triangle by passing deep to trapezius m. which it supplies
transverse cervical a.
branches from thyrocervical trunk laterally and inferior to the origin of the transverse cervical
- crosses posterior triangle inferiorly, medial and deep to the inferior belly of omohyoid muscle
suprascapular a.
- paralleled by accompanying v. is joined by suprascapular n. as it passes out of the posterior triangle laterally to enter the scapular region
arises from subclavian opposite the thyrocervical trunk to descend inferiorly into the thorax posteriot o the sternal end of the clavicle and junction of the subclavian and internal jugular vv. it is crossed anteriorly by the phrenic n.
internal thoracic artery
passes posterior from the subclavian a. over the cupola of lung underneath the anterior scalene
costocervical trunk (Part II)
ascends dorsal to the brachial plexus between the semispinalis cervicis and capitis mm. will anastomose witih the descending branch of the occipital a.
deep cervical a.
descends anterior to the head of the 1st rib, provides the posterior intercostal a. to the first intercostal space and terminates forming the 2nd posterior intercostal a.
highest intercostal a.
may rise from part II or part III. passes dorsal through the brachial plexus when present, reaches levator scapulae and descends under the rhomboid muscles to participate in scapular anastomosis
dorsal scapular a.
what forms the brachiocephalic beins?
internal jugular v. and subclavian v.
central venous line placement
the subclavian v. is often used as point of entry for placement. technically you are sticking axillary v. with needle, but it travels to reach the subclavian v.
