Week 7: Anatomy of Neck Flashcards
superficial cervical fascia
- lies between skin and deeper layer of cervical fascia
* contains superficial veins (external jugular), lymph nodes, adipose tissue, and the platysma muscle
deep cervical fascia
3 layers •investing layer •prevertebral layer •pretracheal layer •Carotid sheaths
investing layer of deep cervical fascia
- most superficial
* surrounds all structures in neck
prevertebral layer of deep cervical fascia
surrounds vertebral column and deep muscles of the neck
pretracheal layer of deep cervical fascia
- encloses viscera of neck
* posterior part is referred to as the buccopharyngeal fascia
what are the viscera of the neck
pharynx, esophagus, thyroid gland, and trachea
carotid sheaths of deep cervical fascia
surround neurovascular bundles on either side of neck (common carotid artery, internal jugular vein, and vagus nerve)
between the fascial layers of the neck
•potential spaces that may provide conduit for spread of infection
pretracheal space
between investing layer and pretracheal layer of deep cervical fascia
retropharyngeal space
between buccopharyngeal fascia and prevertebral facia
third space
WITHIN the anterior part of the prevertebral fascia covering the bodies of the vertebrae
anterior triangle of the neck
bounded by the anterior border of the sternocleidomastoid muscle, inferior border of the mandible, and the midline of the neck
posterior triangle of the neck
defined by posterior border of sternocleidomastoid muscle, anterior border of trapezius, and clavicle
function of suprahyoid muscles
raise the hyoid bone toward the mandible during swallowing
innervation of suprahyoid muscles
facial or trigeminal nerve
function of infrahyoid muscles
depress the hyoid bone and larynx during swallowing and vocalization
innervation of infrahyoid muscles
branches of the cervical spinal nerves (ansa cervicalis)
function of scalene muscles
- act as accessory muscles of respiration
* flex the neck
innervation of scalene muscles
branches of cervical spinal nerves (ansa cervicalis)
location of scalene muscles
- there is anterior, middle, and posterior
* located in lateral aspect of neck in posterior triangle
scalene muscles are important landmark for what in the neck?
subclavian artery and brachial plexus pass between the anterior and middle scalene muscles
supply of thyroid gland
- superior thyroid artery (1st branch of external carotid artery)
- inferior thyroid artery (branch of thyrocervical trunk off subclavian artery)
thyroid gland is rich in veins that empty to
either internal jugular vein or brachiocephalic vein
laryngeal nerves and thyroid
- the recurrent laryngeal nerves pass deep to the lateral lobes of they thyroid to enter the larynx
- they are at risk of nerve injury during surgical removal or manipulation of thyroid
parathyroid glands location
normally found on deep surface of lateral lobes of thyroid, though their location can be highly variable
parathyroid glands function
responsible for PTH, that acts to regulate the calcium levels in the body
considerations to take during tracheotomy
location of thyroid; isthmus may be encountered and may have to be retracted or divided
considerations to take during cricothyrotomy
location of thyroid; is a pyramidal lobe is present, it may interfere with access to cricothyroid membrane
right and left common carotid arteries
- ascend up neck in the carotid sheath, lateral to the trachea and esophagus
- do not give off any branches
internal carotid artery
gives off no branches in neck, but enters skull to provide blood to brain
external carotid
- has 7 branches: superior thyroid, ascending pharyngeal, lingual, facial, occipital, posterior auricular, and maxillary
- ends as the superficial temporal artery
cervical nerve plexus
network of nerve fibers for motor and sensory innervation to structures of neck and trunk
cervical nerve plexus formed by
formed from anterior rami of C1-C4 spinal nerves
cervical nerve plexus located
in the posterior triangle of neck
important motor branches of cervical plexus
- phrenic nerve (C3-C5) - motor to diaphragm
* ansa cervicalis (C1-C3) - motor to infrahyoid muscles
sensory branches of cervical plexus supply
skin of neck, upper thorax, scalp, and ear
Erb’s point
- where sensory branches of cervical plexus enter the skin
* middle of posterior border of sternocleidomastoid
4 major branches of cervical plexus
lesser occipital, greater auricular, transverse cervical, and supraclavicular nerves
Where is a cervical nerve block done
Erb’s point
Where do the common carotids split
about the level of thyroid cartilage; they split into external and internal carotid arteries
