Nerves Flashcards
Greater occipital nerve
Sensory Branch of dorsal ramus of C2
Emerges from between C1 and C2, inferior to obliquus capitis inferior
Sensation from the back of the head
Least (3rd) occipital nerve
Sensory branch of dorsal ramus of C3
Inferior to greater occipital nerve
Sensation from posterior of head and neck
How does the vagus nerve (CN X) travel through the neck?
Between the common carotid artery and internal jugular vein within the carotid sheath
How does the hypoglossal nerve (CN XII) travel through the neck?
Deep to posterior belly of digastric - between internal carotid artery and internal jugular vein - crosses over external carotid artery to loop anteriorly - dives between mylohyoid and hyoglossus muscles (traveling with lingual artery)
Where is the cervical portion of the sympathetic trunk found?
Deep to contents of carotid sheath
Against pre-vertebral muscles
Name the ganglia typically found in the cervical portion of the sympathetic trunk
Superior
Middle
Inferior
Vertebral
Cervicothoracic (stellate) ganglion
The common fusing of the inferior cervical ganglion and the first thoracic ganglion of the sympathetic trunk
Typically posterior to subclavian artery
Ansa subclavia
Thin loop of sympathetic fibers that travel anterior to subclavian artery
Connect stellate ganglion to vertebral ganglion
Carotid plexus
Sympathetics traveling above superior cervical ganglion
Travel with the carotid vessels
Superior cervical gangion
Sympathetics to head
Middle cervical ganglion
Sympathetics to heart and lungs
Inferior cervical ganglion
Sympathetics to heart and lungs
Horner’s syndrome
Lesion of sympathetic trunk in neck
Causes: stroke, neck trauma, carotid artery injury, Pancoast tumors (top of lungs), cluster headaches
Symptoms:
- miosis (contraction of pupil)
- ptosis (drooping of eyelid)
- anhidrosis (decreased sweating face/neck)
Branchial fistula
Abnormal canal resulting from the persistence of remnants of the 2nd pharyngeal pouch
Passes through subcutaneous tissue, platysma, fascia of neck to enter carotid sheath
Passes between internal and external carotid arteries to tonsillary sinus
Usually travels along anterior of SCM
Saliva may drip from fistula - infection
How does the brachial plexus course through the neck?
Travels between anterior and middle scalene - between clavicle and first rib
How does the phrenic nerve course through the neck?
C3, C4, C5
Runs anteriorly to anterior scalene - enters thorax - runs along pericardium - diaphragm
How does the accessory nerve (CN XI) course through the neck?
C1-C6
Enters skull through foramen magnum - leaves skull through jugular foramen - deep to levator scapulae to trapezius
Innervates SCM and trapezius
How does the olfactory nerve (CN I) pass through the skull?
Olfactory foramina (ethmoid bone)
How does the optic nerve (CN II) pass through the skull?
Optic canal (sphenoid bone)
How does the oculomotor nerve (CN III) pass through the skull?
Superior orbital fissure (sphenoid bone)