Posterior Cervical Triangle Flashcards
What is the superficial fascia comprised of?
loose connective tissue and fat
What is the dense organized connective tissue layer of fascia and what is it missing?
deep fascia. fat
What does deep fascia envelop?
most body structures deep to skin and subcutaneous tissue
- compartmentalizes them
Which fascia layer is made up of many layers?
deep
What is an example of a muscle found in superficial neck fascia?
platysma m
What does the deep fascia aid in?
muscle movements, provides passageways for nn and vessels and provides attachment for some mm
What is a tube that provides continuity from the head to the trunk?
neck
What are the compartments within the neck?
1 visceral component (anterior), 1 vertebral (posterior) and 2 vascular (laterally)
What does the visceral component contain?
digestive and respiratory systems as well as some endocrine glands
What does the vertebral component contain?
cervical vertebrae, spinal cord, cervical nn and mm associated with vertebral column
What do the vascular components contain?
major vessels and vagus n (CN X)
What are types of deep fascia of the neck?
investing, pretracheal, buccopharngeal, alar, prevertebral, carotid sheath
What does the investing fascia surround?
trapezius, SCM mm and infra hyoid mm
What does the pretracheal fascia surround?
thyroid, trachea and esophagus and post surface of infrahyoid mm
What does the buccopharyngeal fascia surround?
- special area of pretracheal fascia
- pharynx posteriorly, portion of visceral fascia that resides on posterior pharynx
What does the alar fascia surround?
anterior layer of prevertebral and deep back mm
What does the prevertebral fascia surround?
prevertebral and deep back mm
What does the carotid sheath surround?
common carotid a, internal carotid a, internal jugular v and vagus n
What layers contribute to the carotid sheath?
investing, pretracheal and prevertebral fascia
In which view is the carotid space not visible?
sagittal view
What are the types of fascial spaces?
carotid sheath, pretracheal space, retropharyngeal space, prevertebral “danger” space
Where does the carotid sheath lie between? What forms it?
SCM and prevertebral mm
- formed by condensations of deep cervical fascia
What does the carotid sheath encase?
carotid aa, IJVs and vagus nn
Where does the carotid sheath extend? What can this cause?
from skull into middle mediastinum (heart)
- infections or blood may spread with sheaths
Where is the pretracheal space?
- between trachea and infrahyoid mm
- from thyroid cartilage down into anterior mediastinum
Which space does not extend to the cranial base?
pretracheal space
Where is the retropharyngeal space?
- between buccopharyngeal and alar fascia
- from skull base into superior mediastinum (bifurcation of trachea)
What space can fill if hold in sneeze?
retropharyngeal space fills with air, if filled with fluid takes longer to resolve
Where is the prevertebral “danger” space?
- between alar and prevertebral fascia
- from skull base to posterior mediastinum
Why is the ‘danger’ space bad?
notorious for inferior spread of infections here
Where is zone I of the neck?
thoracic inlet to cricoid cartilage
Where is zone II of the neck?
cricoid cartilage to angle of mandible
Where is zone III of neck?
angle of mandible to base of skull
Why are the horizontal zones of the neck useful?
used in clinical assessment of neck trauma (ER)
What are the boundaries of the posterior cervical triangle?
SCM = anterior
trapezius m = posterior
middle 1/3 of clavicle = inferior boundary
What are the contents of the posterior cervical triangle?
platysma m, external jugular v, cutaneous nn, motor nn, transverse cervical and supra scapular aa, deep muscles
What are the superficial contents of the post cervical tri?
platysma m and external jugular v
What are the cutaneous nn found in the post cervical triangle?
lesser occipital (C2,3), greater auricular (C2,3), transverse cervical (C2,3), supraclavicular nn (C3,4)
Where do all of the cutaneous nn emerge?
deep to SCM at erb’s point
Where does the lesser occipital n (C2,3) run?
superiorly along post border of SCM
What does the lesser occipital n cross?
portion of occipital a
What does the LON supply?
skin of scalp at apex of triangle
Where does the greater auricular n run?
with EJV sup toward ear, ascend vertically on surface of SCM
What does the GAN supply?
lobe of skin post to auricle and angle of mandible to mastoid process
Where does the transverse cervical n run?
transversely across middle of SCM
What does the TCN supply?
skin of anterior cervical triangle and lateral neck
What are the branches of supraclavicular n?
medial, intermediate and lateral (post) nn
Where does SCN run?
superficial to clavicle and deep to platysma
What does SCN supply?
skin of clavicular region
What motor nerves lie in the post cervical triangle?
accessory and phrenic(C3-5) nn
Where does the accessory n emerge?
from jugular foramen of skull
Where does the accessory n run?
diagonally thru triangle deep to investing fascia
What does accessory n supply?
SCM and trapezius mm
Where does the phrenic n descend?
vertically along ant scalene m
What cross the phrenic n anteriorly?
transverse cervical a and supra scapular a
Where does the phrenic n enter thorax?
between subclavian v and a
What does the phrenic n travel along?
pericardial sac to supply diaphragm
Why is there referred pain in pleurisy?
phrenic and supraclavicular nn share similar origins (C3-5 vs 3-4) so irritation of phrenic n referred from diaphragm to supraclavicular n in clavicular region
What are the vessels of the post cervical triangle?
EJV, transverse cervical a and suprascapular a
Where does the EJV drain?
into subclavian v
Where are the transverse cervical and supra scapular a from?
thyrocervical trunk
Where does the transverse cervical a and suprascapular a run?
- slightly post to triangle and ant to scalene m
- laterally down, post to clavicle
What are the deep mm of the post triangle?
splenius capitis, levator scapulae, 3 scalene mm, omohyoid m
What is the function of the splenius capitis m?
extend and laterally rotate head neck
What innervates splenius capitis m?
dorsal rami of spinal nn
What does the elevator scapulae m do? what innervates it?
elevate scapula, dorsal scapular n (C5)
What are the three scalene muscles and their function/ innervation?
anterior, middle and posterior
- tilt neck laterally
- ventral rami C3-8 nn
Where does the inter scalene triangle lie?
deep to post cervical triangle
What forms the inter scalene triangle?
ant scalene, middle scalene and 1st rib
What passes through inter scalene triangle?
brachial plexus and subclavian a
What passes ant to anterior scalene m?
subclavian v (not part of scalene triangle)
What may contribute to thoracic outlet syndrome?
anatomical variations of interscalene triangle
