Anatomy Flashcards
Dermatomes
Pharynx innervation
IX: glosopharyngeal
XII: hypoglossal
cartilages of the larynx
hyoid
thyroid
cricoid
aretynoid (attached to cricoid and have attached to them the VCs)
epiglottic
Larynx Innervation
CN X
- SLN
- RLN
SLN
- internal laryngeal branch: pierces thyrohyoid membrane–sensation from epiglottis to vocal cords
- external laryngeal branch: cricothyroid muscle (tensor of vocal cords)
RLN
- sensation below vocal cords, motor to all laryngeal muscles except cricothyroid
- bilateral injury–adduction of vocal cords and rapid, severe respiratory obstruction
- enters larynx psoterior to cricothyroid articulation–blocked by transtracheal approach
- RLN runs in a groove between trachea and esophagus–blocked by stellate ganglion block
Tracheal Innervation
Vagus CN X
Roots of brachial plexus
anterior primary divisions C5-8 +T1, with contributions from C4 and T2
Division of brachial plexus
Robert Taylor Drinks Cold Beer
Roots
Trunks
Divisions
Cords
Branches
Roots
-anterior primary division of C8-T1, emerge from intervebral foramina, fuse above first rib
Trunks
-above first rib
Divisions
-Each trunk forms anterior and posterior divisions
Cords
- 3 cords: medial, lateral, posterior
- medial/lateral:flexor surfaces of UE
- posterior cord: extensor surfaces of UE
Branches-Terminal nerves
Lateral/medial cord: lateral/medial head of median
medial cord: ulnar
lateral cord: musculocutaneous
posterior cord: axillary, radial
axillary nerve block
- prevertebral fascia forms axillary perivascular sheath, which envelopes the brachial plexus and axillary artery
- median nerve: above ax artery
- ulnar nerve: below ax artery
- radial nerve: posterior/inferior to artery–needle passes posterior wall of ax artery
- misses musculocutaneous b/c came off already
interscalene block
- at level C6/cricoid cartilage
- between anterior and middle scalene muscles
- brachial plexus and subclavian artery run together
- needle enters skin posterior to posterior border of sternocleidomastoid muscle behind the EJ
- anterior scalene is just posterior to the posterior aspect of sternocleidomastoid at the level of the cricoid
supraclavicular block
- enter skin 1-2 cm above midpoint of clavicle and elicit paresthesias as needle advanced toward 1st rib
- when first rib contacted, needle moved in anteroposterior direction until paresthesias elicited
cutaneous nerves of the hand
radial nerve block at elbow
-between brachioradialis and biceps tendon
radial nerve block at wrist
- nerve is lateral to radial artery
- NA/N/AN-lateral to medial
- breaks for flexor carpi radialis and palmaris longus
- both radial and ulnar located outside
ulnar nerve at elbow
- between olecranon and medial epicondyle of humerus
- usu blocked above elbow to avoid direct nerve trauma
- loss of all muscles of hand except thenar eminence and 1st/2nd lumbricals
ulnar nerve at the wrist
-medial to ulnar artery
median nerve at the elbow
=blocked medial to brachial artery between two heads of pronator teres
median nerve supplies
-thenar eminence, 1st and 2nd lumbricals
median nerve at the wrist
-between flexor carpi radialis and palmaris longus
injury to nerves
- direct needle or other trauma, or ischemia from positioning
- supplied by arteries called vasa nerovrum
Cutaneous nerves of leg : back
Cutaneous nerves of leg: front
nerve supply to LE
- Lumbar plexus: T12, L1, L2, L3,L4-femoral, obturator, lateral femoral cutaneous, ilioinguinal, iliohypogastric, genitofemoral
- sacral plexus: L4, L5, S1, S2-Sciatic nerve
Femoral nerve block
- passes under inguinal ligament, dividing into anteiror and posterior divisions
- sensory to anteiror and medial thigh and leg
- sensory to medial ankle (saphenous)
- NAVL
lateral femoral cutaneous nerve
-sensory to anterolateral spect of thigh down to knee
meralgia paresthetica
-compression of lateral femoral cutaneous nerve by inguinal ligament, producing pain, numbness, paresthesia over anterolateral aspect of thigh
obturator nerve
-adductors of the thigh
sciatic nerve
- sacral plexus–>greater sciatic notch–>popliteal region–>divides into tibial and common peroneal nerves
- sciatic nerve: hammstrings and all msucles of leg and foot
- sciatic nerve: snesory to front (superficial/deep peroneal), back (posterior tibial), lateral (Sural) ankle
sciatic nerve block
- lateral position with hip and knee flexed
- line drawn between posterior superior iliac spine and greater trochanter
- at midpoint of this line, a perpendicular (bisecting line) drawn 3 cm downward
- surgery for sole of foot
- if surgery involves lE–combine with femoral, obturator or lateral femoral cutaneous nerve
superficial peroneal nerve
- line connecting medial and lateral malleolus–place a cuff of anesthesia along it
- sensory to dorsum of foot and toes except great and 2nd toes
deep peroenal nerve
- lateral to ex hallucis longus to great toe
- flexors of toes and provides sensation between great and second toes
sural nerve
- posterior to lateral malleolus
- sensory to posterolateral leg, lateral foot, 5th toe
posterior tibial
- posterior to medial malleolus
- sensory to sole of foot, plantar surface of foot
saphenous nerve
- from femoral nerve
- anterior to medial malleolus
- sensory to anteromedial side of leg and medial side of the foot
ankle block
sole of foot innervation
gasserian ganglion
- a trigeminal nerve block
- anesthesia to ipsilateral face, cornea, sclera, anterior tongue
- used for trigeminal neuralgia
- posterior tongue is covered by CNIX
- middle cranial fossa, close proximity to dural fold and meckel’s cave containing CSF
- if needle goes too far, can enter cranial CSF–produce other nerve involvement (facial) or total spinal
superficial cervical plexus block
- anterior branches of first 4 cervical nerves
- superficial at lat border of SCM, blocked with 10 cc 1% lido subq
- success=horner’s syndrome and hoarsenes (RLN block)
- complications: phrenic nerve paralysis, subarachnoid block
intercostal nerve block
- anterior rami of first 11 Thoracic nerves
- neurovascular bundle below each rib (VAN–nerve inferior)
branches of intercostal nerves
1) sympathetic ganglion
2) posterior cutaneous branch–skin and muscle oin paravertebral region
3) lateral cutaneous branch–skin of medial arm for T2–intercostobrachial nerve
