Brachial plexus Flashcards
what is the brachial plexus?
ventral rami of C5-T1, innervates the upper limb and girdle
What are the components of the brachial plexus from medial to deep?
roots
Trunks
divisions
cords
nerves/branches
what forms the medial border of the brachial plexus
deep to sternocleidomastoid and anterior scalene
what forms the lateral border of the brachial plexus?
axilla
what are the roots of the brachial plexus?
ventral rami C5-T1
what are the trunks of the brachial plexus?
upper, middle, and lower trunks formed from the merging of roots
what are the divisions of the brachial plexus?
each trunk divides into anterior and posterior divisions
what are the cords of the brachial plexus?
the 6 divisions converge to form 3 cords: lateral, medial, posterior
what are the Nerves/ branches of the brachial plexus
5 major nerves that emerge from the 3 cords: musculocutaneous, median, ulnar, radial, axillary
Branches off of roots from the brachial plexus form the _____ ______ nerve and _______ ______ nerve
dorsal scapular
long thoracic
what does the dorsal scapular nerve innervate?
rhomboids and a portion of the levator scapulae
what does the long thoracic nerve innervate?
serratus anterior
Branches off of trunks from the brachial plexus form the nerve to _________ and the ________ nerve
nerve to subclavius, suprascapular nerve
what does the nerve to subclavius innervate?
subclavius
what does the suprascapular nerve innervate?
supraspinatus and infraspinatus
Branches off of the medial and lateral cords of the brachial plexus form __________ and ________ ___________ nerves and _______ _________ nerves
medial and lateral pectoral nerves and medial cutaneous nerves
what do the medial and lateral pectoral nerves inneravate?
pectoralis major and minor
what do the medial cutaneous nerves innervate?
skin of medial arm and forearm
branches off the posterior cord of the brachial plexus form the _______ and _________ _________ nerves and _________ nerve
upper and lower subscapular
thoracodorsal
what do the upper and lower subscapular nerves innervate?
subscapularis and teres major
what does the thoracodorsal nerve innervate?
latissimus dorsi
the ___________, _________, and ___________ nerves innervate the anterior compartment muscles and a large portion of the anterior skin of the upper limb
musculocutaneous, median, and ulnar nerves
what do the musculocutaneous, median, and ulnar nerves innervate?
anterior compartment muscles and a large portion of anterior upper limb skin
what do the radial and axillary nerves innervate?
posterior compartment and large portion of posterior skin of the upper limb
the _______ and _________ nerves innervate the posterior compartment muscles and a large portion of the posterior skin of the upper limb
radial and axillary
what does the musculocutaneous nerve innervate?
coracobrachialis, biceps brachii, branchialis (muscles of anterior arm)
skin of lateral forearm
what does the median nerve innervate?
pronator teres
flexor carpi radialis
palmaris longus
flexor digitorum superficialis
lateral portion of flexor digitorum profundus
flexor pollicis longus
pronator quadratus
3 thenar muscles
2nd and 3rd lumbricals
i.e. MOST MUSCLES OF LATERAL FOREARM AND HAND
skin of lateral palm and lateral 31/2 digits
what does the ulnar nerve innervate?
flexor carpi ulnaris
medial portion of flexor digitorum profundus
hypothenar muscles
adductor pollicis
4th and 5th lumbricals
interossei muscles
i.e. MOST MEDIAL MUSCLES OF FOREARM AND HAND
skin of medial palm and dorsum
medial 1/2 digits
what does the ulnar nerve pass behind?
medial epicondyle of humerus (funny bone)
what is guyons canal?
osseofascial space that extends between pisiform and hook of the hamate that allows the ulnar nerve and ulnar artery to pass into the palm
what does the axillary nerve innervate?
deltoid
teres minor
skin over deltoid
what does the radial nerve innervate>
triceps brachii
anconeous
brachioradialis
extensor carpi radialis
extensor digitorum
extensor digiti minimi
extensor carpi ulnaris
supinator
abductor pollicis longus
extensor pollicis (longus and brevis)
extensor indicis
i.e. Muscles of posterior arm and forearm
skin of posterior arm, forearm, and dorsolateral hand
