Musculocutaneous Nerve

Question 1

Name the nerve roots and origin or cord.

Answer 1

lateral cord of brachial plexus

formed from anterior divisions of superior and middle trunks

Question 2

Name it’s course?

Answer 2

it leaves the axilla by piercing coracobrachialis muscle
it then passes down the arm beneath biceps muscle
it ends as the lateral cutaneous nerve of forearm

Question 3

Sensory supply?

Answer 3

Skin of lateral forearm.

Question 4

Fetaures of injury/ nerve palsy?

Answer 4

SENSORY LOSS
numbness over lateral forearm

MOTOR DEFICIT
paralysis of anterior compartment of arm – very weak elbow flexion and weak forearm supination
absent biceps reflex

DEFORMITY
wasting of anterior compartment of arm
elbow usually held in extension with forearm pronated