neck overview Flashcards
hyoid bone
opposite CV3
thyroid cartilage
opposite CV4/5
Cricoid cartilage
opposite CV6
superficial fasica
fat and CT
contains Platysma m
platysma
superficial fascia covering pec major and deltoid
inferior margin of mandible, skin, and subQ tissues of lower portion of face and corner of mouth
draws corner of mouth down, depress mandible, elevates skin of chest
cervical br of VII
deep fasicas
investing infrahyoid (superficial and deep) cervical (pre-tracheal and buccupharyngeal) pre-vertebral alar
investing fascia
surrounds entire neck, providing roof for triangles
invests trap and SCM
continuous superiorly with parotid fascia
forms capsule for submandibular gland
investing fascia attachments
sup- external occipital protuberance, superior nuchal line, mastoid process, and inf margin of mandible
post- external occipital protuberance, spinous processes of CV1-7 via nuchal lig
inf- blends with inf attachements of SCM and tap to attach to clavicle, also attaches to spine of scap, acromion, manubrium
infrahyoid fascia
begins at hyoid bone and thyroid cartilage forms 2 layers:
superficial
deep
these invest infrahyoid mm and eventually fuse with:
inf- adventitia of brachiocephalic vv, fibrous pericardium via superior sternopericardial ligament
lat- carotid sheath
superficial layer of infrahyoid fascia
invests sternohoid and omohyoid mm
inf- attaches to posterior surface of manubrium
lat- fuses w/periosteum of clavicle and 1st rib
forms sling for tendon of omohyoid m
deep layer of infrahyoid fascia
invests sternothyroid and thyrohyoid mm
inf- attaches to posterior surface of manubrium
cervial fascias
encircle visceral structures of neck have and ant and post portion which fuse lat:
pretacheal
buccopharyngeal
pretracheal
located ant to larynx and trachea
attached to hyoid bone sup
blends lat with the buccopharyngeal fascia
splits to enclose thyroid gland
inf blends with adventitia of aortic arch and fibrous pericardium
buccopharyngeal
attaches sup to base of skull, externally covers buccinator and pharyngeal constrictor mm
laterally fuses with pretracheal fascia
inferior blends with adventitia of esophagus
pre-vertebral fascia
continuous w/nuchal fascia post to encircle VC and mm
sup- base of skull ant and lat to VC
ant- covers pre-vertebral mm and extends inf into post mediastinum (becomes alar)
lat- attaches to cervical transverse processes
forms floor of post cervical triangle
covers scalenes, levator scapulae, and semispinalis
post- nuchal portion from nuchal lines and mastoid processes to cercial spinous processes, inf fuses w/thoracolumbar fascia
alar fasica
ant bifurcation of pre-vertebral fascia
attaches to midline of buccopharyngeal fascia
bilaterally blends with carotid sheath
inf blends with adventitia of esophagus
specializations of pre-vertebral fascia
sibsons fascia
axillary sheath
sibsons fascia
aka suprapleural membrane
prevertebral layer of fascia is continued onto underside of scalene mm and reinforces the dome of cervical pleura
axillary sheath
continuation of prevertebral fascia reflected from scalenes laterally along subclavian and axillary vessesls and brachial plexus as they pass thru scalene triangle
carotid sheath
surrounds common and internal jugular aa, internal jugular v and X
sup- base of skull at margins of jugular foramen and carotid canal
inf- fuses w/adventitia of great vessels and fibrous pericardium
ALL deep fascias of neck blend bilaterally with carotid sheath
cervical fascial spaces
suprasternal
pretracheal/visceral
retropharyngeal spaces
suprasternal space
made from investing fascial layers
where they fail to fuse at base of SCM
filled with fat and contains v which communicates with inf ant jugular vv
pretracheal/visceral space
btwn deepest layer of infrahyoid fascia and pretracheal fascia
retrophayngeal spaces
1) retropharyngeal/retrovisceral/retroesophageal
- smaller ant
- btwn buccopharyngeal and alar fascias
2) danger space
- larger post
- btwn pre-vertebral and alar/buccopharyngeal fascias
danger space
can lead to retropjaryngeal abcess -> dysphagia and dysarthia
can spread to superior and post mediastinum and as far as diaphragm
boundaries of neck
ant- line drawn from symphysis menti to sternal notch
post- trap
sup- indefinite line that connects the superior nuchal line, mastoid process, and inf margin of mandible to symphysis menti
inf- superior margin of clavicle, sternoclavicular joint, and sternal notch
SCM
sternal head- manubrium
clavicular head- proximal 1/3 clavicle
mastoid process, superior nuchal line
unilateral- rotates head toward opposite side while elevating chin
bilateral- flex head, limited extension of atlanto-occipital joint
XI, C2,3
torticollis
aka wry neck
congenital or acquired
shortening of SCM
patients head becomes side bent (same side) and rotated to opposite side
Posterior triangle boundaries
trap, SCM, clavicle
subdivided by omohyoid m into:
occipital triangle
omoclavicular/subclavian/supraclavicular triangle
occpital triangle
larger more superior
bounded by trap, SCM, and inf belly omohyoid
omoclavicular triangle
aka subclavian
aka supraclavicular
smaller more inferior
bounded by inf belly omohyoid, SCM, clavicle
anterior triangle
bounded by SCM, angle of mandible, imaginary line mid-sagitally
subdivided by digastric and omohyoid mm into:
digastric/submandibular triangle
submental triangle
carotid triangle
muscular triangle
diagastric triangle
aka submandibular
bounded by inf margin of mandible and 2 bellies of diagastric m
submental triangle
bounded lat by 2 opposing ant bellies of diagrastric mm and hyoid bone
carotid triangle
bounded by post belly of diagastric, superior belly of omohyoid, and SCM
muscular trianlge
supeior belly of omohyoid, SCM, and median line of neck to hyoid bone
External jugular vv
union of post division of retromandibular and post auricular vv at angle of mandible
descends superficial to SCM, pierces investing fascia at root of neck post to clavicle, terminates at subclavian v
tributaries of external jugular vv
posterior external jugular
transverse cervical
suprascapular
ant jugular
anterior jugular vv
small vv in submental and submandibular regions coalesce at level of hyoid bone to form ant jugular
descends in ant triangle-> pierces investing fascia -> thru suprasternal space where it communicates w/contralateral v via jugulovenous arch -> turns lat to couse deep to SCM and join external jugular v
C1 dorsal rami
only 50% of ppl have dorsal root
been taken over by C2 (greater occipital n)
small amount that remains comes from dura lining posterior cranial fossa
C2 dorsal rami
greater occipital n
pierces semispinalis capitis and trap ascends to innervate skin over certex and posterolateral skull
C3-6 dorsal rami
dorsal rami pierce deep musculature to reach sub Q areas on dorsal midline and extend laterally to cutaneous areas over trap
C1-4 ventral rami
form cervical plexus
C2-4 ventral rami
cuntaneous innervation of pinna, ant, and post to ear, lat and ant neck, upper ant thorax, and prominence of shoulder
lesser occipital n
C2,3
ascends post border of SCM to innervate medial surface of ear as well as skin behind ear
great auricular n
C2,3
ascends lat surface of upper half of SCM toward angle of mandible paralleling the external jugular
provides brr to skin covering mastoid process, lower portion of both surfaces of ear, and inf angle of mandible and parotid region
transverse cervical n
C2,3
crosses lat surface of SCM inf to greater auricualr n and deep to external jugular v
w/in ant triangle travels deep to platysma dividing into sup and inf brr
these pierce platysma to innervate skin and subQ of ant triangle down to sternum
supraclavicular nn
C3,4 arise from common trunk which crosses portion of post triangle and divides into 3 brr medial supraclavicular intermediate supraclavicular lateral supraclavicular
medial supraclavicular n
crosses the inf portion of SCM to provide brr to skin at base of neck, upper sternum, and steroclavicular joint
intermediate clavicular
crosses clavicle to innervate skin over pec major down to rib 3
lateral supraclavicular
crosses clavicule in area of AC joint (supplying it) and cutaneous innervation to prominence of shoulder
superficial cervical lymph nodes
submental submandibular external jugular anterior jugular drain to deep cervical nodes that parallel internal jugular v
