Triangles of the Neck Flashcards
where does the superficial fascia lie?
between the dermis and the investing layer of the deep cervical fascia
what are the 3 fascial layers (sheaths) of the deep cervical fascia?
investing, pretracheal, and prevertebral
what is the most superficial layer of the deep cervical fascia?
the investing layer
what does the investing layer enclose?
the SCM and trapezius muscle; the parotid and submandibular glands
where is the pretracheal fascia located?
in the anterior neck
what does the pretracheal fascia blend with?
pericardium
what does the pretracheal fascia contain?
the infrahyoid muscles and buccopharyngeal fascia
what does the prevertebral fascia enclose?
the vertebral column and associated muscles
What does the carotid sheath cover?
carotids, IJV, and vagus nerve
where is the retropharyngeal space located?
posterior to pharynx and esophagus
what is the purpose of the retropharyngeal space?
it permits movement of the pharynx, larynx, and esophagus during swallowing
what provides an easy route for upper respiratory or oral infections to spread?
retropharyngeal space
What does the retropharyngeal space separate?
the carotid sheath and the pretracheal fascia from the prevertebral fascia
what is the structure separating the anterior and posterior triangle of the neck?
the SCM muscle
what are the borders of the posterior triangle fo the neck?
posterior border of the SCM (anterior border), anterior border of the trapezius (posterior border) and the middle third of the clavicle (inferior border)
what are the borders of the anterior border of the neck?
midline of neck (anterior boundary), anterior border of the SCM (posterior border), inferior border of the mandible (superior border)
How is the posterior triangle further broken down?
into occipital and supraclavicular triangles
What separates the occipital triangle from the supraclavicular triangle?
the inferior belly of the omohyoid muscle
what fascia makes up the floor of the posterior triangle?
prevertebral fascia
What cutaneous nerves emerge from beneath the SCM and enter the occipital triangle?
lesser occipital nerve, greater auricular nerve, transverse cervical nerve, and suprascapular nerve
What is the main nerve found in the posterior triangle?
spinal accessory nerve
What are the muscles found on the floor of the posterior triangle?
splenius capitis m, levator scapulae, posterior scalene, middle scalene, inferior belly of omohyoid, sometimes inferior portion of anterior scalene (usually hidden under SCM)
Where does the posterior scalene originate from?
the posterior tubercles of C5-C7 transverse processes
where does the posterior scalene insert onto?
2nd rib
where does the middle scalene muscle originate from?
posterior tubercles of C2-C7 transverse processes
where does the middle scalene muscle insert into?
superior 1st rib
where does the anterior scalene originate from?
anterior C3-C6 transverse processes
where does the anterior scalene insert onto?
1st rib
contraction or shortening of the cervical muscles that produces twisting of the neck and slanting of the head
torticollis
what is congenital torticollis?
when a fibrous tissue tumor within the SCM causes the head to turn to the side and the face to turn away from the affected side
What is muscular torticollis?
when the SCM is injured during a difficult birth, tearing its fibers which leads to a hematoma
what is the motor innervation of the SCM?
spinal accessory nerve
what is the pain and proprioception innervation of the SCM?
C3 and C4
What anterior rami make up the cervical plexus?
C1-C4
What makes up the phrenic nerve?
C3, C4, and C5
what is the role of the phrenic nerves?
provide the sole motor supply to the diaphragm as well as sensation to its central part
what are the branches of the first region of the subclavian artery?
internal thoracic, vertebral artery, thyrocervical trunk
what are the branches of the second region of the subclavian artery?
costocervical trunk
what branches off the costocervical trunk?
superior intercostal and deep cervical artery
what branches off the third region of the subclavian artery?
dorsal scapular artery
what branches off the thyrocervical trunk?
inferior thyroid artery, suprascapular artery, transverse cervical artery
What are the sub triangles of the anterior triangle of the neck?
carotid, submandibular, muscular, and submental
what are the borders of the carotid triangle?
SCM, superior belly of the omohyoid, posterior belly of digastric
what are the borders of the submandibular triangle?
anterior and posterior bellies of digastric and mandible
what are the borders of the muscular triangle?
SCM, superior belly of the omohyoid and midline from hyoid to manubrium
what are the borders of the submental triangle?
both anterior bellies of digastric and hyoid bone
what makes up the floor of the submental triangle?
two mylohyoid muscles
where do the two mylohyoid muscles meet?
in a median fibrous raphe
What is the suprahyoid region?
the submental/submandibular triangle
what makes up the suprahyoid region?
myohyoid m, geniohyoid m, digastric m, and the submandibular gland
what makes up the digastric region?
digastric muscle(2 bellies), stylohyoid muscle, hyoglossal muscle
What are the infra hyoid muscles?
sternohyoid, omohyoid, sternothyroid, thyrohyoid
What are the infra hyoid muscles also known as?
the strap muscles
what do you call a loop of nerve fibers in the neck that is part of the cervical plexus of nerves?
ansa cervicalis
how are the infra hyoid muscles innervated?
by the ansa cervicalis and its branches
what makes up the superior root of the ansa cervicalis?
C1
what makes up the inferior root of the ansa cervicalis?
formed by branches of C2 and C3
Why is the carotid triangle significant?
the common carotid artery ascends into it
Where is the carotid sinus located?
at site of bifurcation of common carotid artery
what does the common carotid artery branch into?
internal and external carotid arteries
what branches off the external carotid artery?
ascending pharyngeal, superior thyroid, lingual, facial, occipital, and posterior auricular
what does the carotid sinus contain?
chemoreceptors and baroreceptors for monitoring O2 and BP levels
What does the external carotid artery terminate into?
maxillary and superficial temporal arteries
where is the thyroid gland located?
deep to the sternothyroid and sternohyoid muscles (from C5-T1)
what unites the two lobes of the thyroid?
a thin isthmus
where is the thyroid gland connected to?
cricoid cartilage and superior tracheal rings
what is the blood supply for the thyroid gland?
inferior and superior thyroid arteries and veins
where are the parathyroid glands located?
they lie on the posterior aspect of the thyroid gland in their own capsule
the laryngeal skeleton consists of how many cartilages?
Nine- 3 are single and 3 are paired
what are the unpaired cartilages of the laryngeal skeleton?
thyroid cartilage, epiglottis, and cricoid
What are the paired cartilages of the laryngeal skeleton?
arytenoid, corniculate, and cuneiform
what are the nerves of the larynx?
superior and inferior laryngeal branches of the vagus nerve
What is the blood supply of the larynx?
superior laryngeal artery off the superior thyroid artery and the inferior laryngeal artery off the inferior thyroid artery
Where are the superficial cervical lymph nodes located?
along the course of the EJV
where does the main group of deep cervical lymph nodes form a chain?
along the IJV
What contains all of the lymph fluid from the chest, lower extremity, and abdomen?
the thoracic duct
