Download NERVE COURSE MOTOR SENSORY INJURY musculocutaneous

NERVE
musculocutaneous
nerve
(C5 – C6 anterior)
median nerve
(C6 - C8 anterior)
ulnar nerve
(C8 – T1 anterior)
medial brachial
cutaneous nerve
(C8 – T1 anterior)
axillary = humeral
circumflex nerve
(C5 – C6 post.)
radial nerve
(C5 – T1 post.)
COURSE
from lateral cord to
between heads of
coracobrachialis
muscle to lateral side
of arm
from later and medial
cord to go with
brachial artery, and
pass ant to medial
epicondyle; no
branches in arm
continues medial
trunk, decends down
medial arm, passes
post. to medial
epicondyle in ulnar
groove; no arm
branches
from medial cord
from post. cord to go
with post. humeral
circumflex artery
through quadrangular
space to post. shoulder
and arm
continues post. cord;
passes post. to triceps
in musculospiral =
radial groove of
humerus with deep
radial artery
MOTOR
flexor musels of the arm:
• coracobrachialis
• biceps brachii
• brachialis
SENSORY
after last muscular branch,
becomes lateral antebrachial
cutaneous nerve to supply
C6 dermatome on radial
forearm
• no motor function in arm none in arm
• in forearm supplies
pronator muscles and
wrist flexors, which
originate from med.
epicondyle and so flex
the elbow weakly
none in arm
• no motor in arm
• in forewarm supplies
wrist and hand flexors
which originate from
medial condyle and so
flex elbow weakly
INJURY
• inability to flex or supinate arm
strongly
• loss of biceps tendon reflex
• loss of lateral forearm
sensation
o suprocondyler fracture could
injure median nerve
o blood draw from cubital fossa
could injure median nerve
• injury leads to deficits in hand
and forearm motion deficits
none
skin on medial side of arm
N/A
• teres minor
• deltoid
becomes superficial distal to
deltoid as superior lateral
cutaneous nerve of arm,
supplying skin over deltoid
muscle
• deltoid paralysis leading to total
inability to abduct arm and
severe shoulder flexion and
extension deficits
• medial muscular
branches to arm extensor
(triceps brachii)
• lateral muscular
branches to anconeous,
brachioradialis, and ext.
carpi radialis longus
• lateral brachial cutaneous
nerve to preaxial arm
• post. = dorsal brachial
cutaneous n. and post. =
dorsal antebrachial
cutaneous n.to dorsal arm
and forearm
• “Saturday night” or crutch palsy
lose extensor musles in arm,
forearm, and wrist (wrist drop)
• midhumeral fracture cause loss
of wrist and hand extensors
(wrist drop), forearm ok
• medial epicondyle fracture may
injure nerve
• pressure on ulnar nerve in ulnar
groove produces funny bone
feelings