Peripheral nerve anatomy Flashcards
3 branches of the trigeminal nerve (CN5)
- opthalamic
- maxillary
- mandibular
what does the glossopharyngeal nerve innervate
- oropharynx
- soft palate
- posterior 1/3 of tongue
- pharyngeal surface of epiglottis
SLN innervation
- base of tongue
- posterior surface of epiglottis
- aryepiglottic fold
- arytenoids
where does the SLN arise from and divide into (pathway)
- arises inferior ganglion of vagus nerve and descends behind the internal carotid at level of the hyoid bone and divides into the external and internal branches
external branch of SLN supplies what
- cricothyroid muscle
internal branch of SLN supplies what
- supplies sensory innervation to the larynx and hypopharynx
RLN innervates what
- vocal folds and trachea
- bilateral damage = resp distress
cervical plexus innervates what and is located where
- muscles, joints and skin in the anterior neck
- located in ventral rami C1-C4
- lies under sternocleidomastoid muscle
what is the brachial plexus composed of
- 5 ventral rami roots
- 3 trunks
- 6 divisions
- 3 cords
- 5 branches
where are the roots, trunks, and divisions of brachial plexus located
- supraclavicular
- posterior triangle of neck
where are the cords and branches of the brachial plexus located
- infraclavicular
- in axilla
location of the 5 roots of brachial plexus
- C5-T1
- from lateral foramina to lateral border of scalene muscles
which roots converge to make the 3 trunks of brachial plexus
- superior trunk C5-C6
- middle trunk C7
- inferior trunk C8-T1
location of brachial plexus trunks
- emerge between anterior and middle scalene muscles
- enveloped in facial sheath
- injection into sheath produces block
what do the 3 ventral divisions of brachial plexus supply
- flexor portions
what do the 3 dorsal divisions of brachial plexus supply
- extensor portions
in the axilla the 3 dorsal divisions combine to form what
- the posterior cord
in the axilla the 3 ventral divisions combine to form what
- the lateral and medial cords
major nerves that branch off of the lateral cord
- musculocutaneous nerve
- median nerve
major nerves that branch off of the medial cord
- medial nerve
- ulnar nerve
major nerves that branch off of the posterior cord
- axillary nerve
- radial nerve
where is the axillary nerve formed and what does it innervate
- formed C5-C6
-innervates the shoulder (deltoid area)
where is the redial nerve formed and what does it innervate
- formed from C5-T1
- innervates triceps, posterior surface of the forearm, hand, thumb, index, middle, and ring finger
radial nerve response to stimulation
- wrist extension
- metacarpo-phalangeal extension
- thumb abduction
where is the musculocutaneous nerve formed and what does it innervate
- formed from C5-C7
- innervates muscles of brachialis and biceps
- innervates skin of elbow and proximal radioulnar joints, lateral forearm (thumb side)
motor response from musculocutaneous nerve
- bicep flexion
where is the median nerve formed and what does it innervate
- from C5-T1
- innervates anterior wrist and distal forearm, the thumb, index and lateral half of ring finger and their nail beds
motor response to median nerve
- wrist flexion
- finger flexion
- thumb opposition
what are the branches of the medial nerve and where are they formed from
- T1
- medial brachial cutaneous branch
- medial antebrachial cutaneous branch
what does the medial brachial cutaneous branch innervate
- innervates skin on medial surface of the arm (bicep area)
what does the medial antebrachial cutaneous branch innervate
- innervates the skin on the medial aspect of the forearm
where is the ulnar nerve formed and what does it innervate
- from C8-T1
- lateral hand innervation, lateral ring finger and the little finger
what does ulnar motor stimulation cause
- ulnar deviation of the wrist
- metacarpo-phalangeal flexion
- thumb adduction
what is the lumbosacral plexus formed from and what does it innervate
- formed from L1-S5
- innervates lower abdomen and lower extremities
iliohypogastric nerve is formed from what and innervates what
- formed from T12-L1
- innervates parietal peritoneum and inferior abdomen and buttocks
ilioinguinal nerve is formed from what and innervates what
- formed from T12-L1
- parietal peritoneum, superior and medial thigh, and portion of external genitalia
genitofemoral nerve is formed by what and innervates what
- formed by L1-L2
- innervates skin over femoral hiatus, scrotum or labia
pudendal nerve is formed from what and innervates what
- formed from S2-S4
- innervates skin and muscle of the perineum
lateral femoral cutaneous nerve is formed from what and innervates what
- formed from L2-L3
- innervates lateral aspect of the thigh to knee
posterior femoral cutaneous nerve is formed by what and innervates what
- formed by S1-S3
- innervates posterior thigh from hip to mid calf
obturator nerve is formed by what and innervates what
- formed from L2- L4
- innervates controls muscles of the hip (ab and adductors) and medial thigh
femoral nerve is formed by what and innervates what
- formed from L2-L4
- innervates anterior thigh and major thigh muscles (rectus, vastus, sartorious)
what is the position of the femoral nerve
- at femoral crease the nerve is lateral to fem artery and vein
- lateral to medial = (NAVEL) nerve, artery, vein, empty space, ligament
saphenous nerve is a branch of what and innervates what
- branch of the femoral nerve
- innervates medial leg from knee to foot
stimulation of the saphenous nerve causes what
- sartorious contraction (bandlike across thigh) and patellar twitch
sciatic nerve is formed by what and innervates what
- formed by junction of the tibial nerve and the common peroneal nerve
- innervates hip extension and flexion of the knee
tibial nerve is formed by what and innervates what
- formed by anterior division of L4-S3
- branches into planter nerves and innervates planter surface of the foot
sural nerve is formed from what and innervates what
- formed from union of tibial and common peroneal nerve
- innervates sole of foot, posterior heel, and achilles tendon
motor response to tibial nerve
- plantar flexion of foot and toes
- inversion of foot
motor response to superficial peroneal nerve
- abduction of foot
- eversion of foot
