Cervical Fascia and Posterior Triangle Flashcards
what are the borders of the neck?
extends anteriorly from the lower border of the mandible to the upper surface of the manubrium; posteriorly from the superior nuchal line on the occipital bone to the intervertebral disc between cervical vertebra 7 to thoracic vertebra 1
what is the Superficial Fascia of the Neck composed of? where is it located? does it contain any muscles/organs? Which, if so?
- noncontractile connective tissue
- composed of loose CT (sometimes fat filled)
- between the skin and deep fascia
- contains the platysma (thin muscle)
what are the boundaries of the platysma muscle?
attached from the superficial fascia of the thorax to the margin of the mandible
How many deep fascia compartments are there in the neck? what are their functions?
5 compartments/tubes;
provide cleavage planes, slippery surfaces facilitate the movement of structures, limit and direct the spread of infection; enclose structure
where is the investing layer located?
fasica that encloses the neck in a continuous layer, attached to bone above and below the neck:
what is enclosed by the investing layer of deep fascia?
splits to enclose the parotid and submandibular glands, the SCM, trapezius muscle, binds down the intermediate tendons of the digastric and omohyoid muscles
what are the attachments of the sternocleidomastoid muscle?
manubrium of sternum and clavicle (inferiorly); mastoid process and superior nuchal line (superiorly)
what are the actions of the SCM?
If acting ALONE: rotates the face to the opposite side while bending the head to the same side
if acting TOGETHER: flex the head and the neck
(both needed to hold the head upright)
What is the SCM innervated by?
spinal accessory nerve (CN XI); pierces the SCM en route to trapezius
What is Torticollis? What is it caused by?
wry neck ( a flexion deformity of the neck)
caused by SCM injuring during child birth due to aggressive pulling on child’s head
Need both SCM to keep the head straight
What does the pretracheal layer enclose?
visceral organs (trachea, esophagus, thyroid gland, pharynx)
what are the attachments of the pretracheal layer? (superiorly and inferiorly)
Superiorly: attaches to the laryngeal cartilages and hyoid bone
Inferiorly: descends anteriorly to the trachea to fuse with the fibrous pericardium
why does the thyroid move with the larynx during swallowing?
Because the pretracheal layer of fascia attaches to both the thyroid gland and the larynx
Where is the Prevertebral fascial layer located?
anterior to the cervical vertebrae; prolongs into the axilla as a sheath for the brachial plexus
What does the carotid sheath enclose?
common carotid, the interjugular vein, and the vagus nerve
In the carotid sheath, the Vagus nerve lies _______ and _____ the artery and vein
behind and between
The carotid fascia lies _____ (thick/thin) over the artery and _____(thick/thin) over the vein, this allows for _________.
thick over the artery, thin over the vein, allows for venous dilation
what other layers of the deep fascia is the carotid sheath continuous with?
continuous with the investing, pretracheal, and prevertebral layers
Where is the buccopharyngeal fascia located?
it is the posterior portion of the pretracheal fascia;
what does the buccopharyngeal fascia separate?
the pharynx and esophagus from the prevertebral fascia
what are the boundaries of the buccopharyngeal fascia?
begins superiorly at the base of the skull and ends inferiorly in the thoracic cavity
what is a fascial space? what is it’s function
are potential spaces that exist between the fascia and underlying organs and other tissues.[3] In health, these spaces do not exist, they are only created by pathology. E.g. the spread of pus or cellulitis in an infection. The fascial spaces can also be opened during the dissection of a cadaver. The fascial spaces are different from the fascia itself, which are bands of connective tissue that surrounds structures, e.g. muscles
where is the retropharyngeal space located
between the buccopharyngeal fascia and the prevertebral fascia
what is the retropharyngeal space
potential space filled with loose CT
what is the function of retropharyngeal space
facilitates movement of the pharynx and larynx during swallowing;
what can happen if an abscess posterior to the prevertebral fascia enters the retropharyngeal space?
it can impinge on the esophagus, causing dysphagia (difficult to swallow) and potentially extend into the posterior mediastinum
where is the pretracheal space located?
potential space between the investing layer (covering posterior sides of infra hyoid muscles) and anterior sides of pretracheal fascia
what is the anterior boundary of the posterior triangle of the neck?
posterior border of the SCM
what is the posterior boundary of the posterior triangle of the neck?
anterior border of the trapezius
what is the inferior boundary of the posterior triangle of the neck?
clavicle
what is the superior boundary of the posterior triangle of the neck?
angle where the SCM and trapezius meet on the superior nuchal line of the occipital bone
what is the roof of the posterior triangle of the neck?
the investing layer of the cervical fascia, platysma, external jugular vein
what is the floor of the posterior triangle of the neck?
levator scapulae and scalene muscles, covered by prevertebral fascia
what are the scalene muscles? what is their attachment site?
a group of small muscles, attached to the transverse process of the ribs;
three of them: anterior middle and posterior scalene muscles
what divides the posterior triangle of the neck?
the inferior belly of the omohyoid into the subclavian and occipital triangles
Where do the contents of the posterior triangle of the neck travel to?
to the upper limb
where do the contents of the anterior triangle of the neck travel to?
thorax
What are the contents of the posterior triangle?
- roots of brachial plexus
- accessory nerve
- cervical plexus
- external jugular vein
- subclavian artery and some of its branches
- lymphnodes
what forms the axilla sheath?
prevertebral fascia
what branches of the brachial plexus can be found in the posterior triangle of the neck?
- dorsal scapular
- suprascapular
- nerve to subclavius
- long thoracic
NOT THE PHRENIC!!
what is nerve block/point of anesthesia in the posterior triangle do?
blocks the nerves of the brachial plexus (provides anesthesia to the upper limb)