Overview
A major peripheral nerve of the anterior compartment of the arm
Origin
A terminal branch of the lateral cord of the brachial plexus (C5, C6 and C7), emerging at the inferior border of the pectoralis minor muscle
Course
- It exits the axilla and pierces the deep surface coracobrachialis muscle near its point insertion on the humerus, supplying it.
- It then emerges from its anterior surface of the coracobrachialis to descend within the anterior compartment of the arm, between brachialis (deep) and biceps brachii muscles (superficially), supplying both.
- At the elbow, it pierces the deep fascia lateral to the biceps tendon and brachioradialis to continue into the forearm.
Termination
It terminates in the lateral forearm as the lateral cutaenous nerve, providing sensory innervation to the lateral aspect of the forearm via dorsal and ventral branches.
Motor Function
Muscles of the anterior compartment of the arm:
- Biceps brachii
- Brachialis
- Coracobrachialis
Sensory Function
Lateral cutaneous nerve of forearm
- Initially enters the deep forearm, but then pierces the deep fascia to become subcutaneous, in close relation to the cephalic vein.
- Innervates the skin of theanterolateral aspect of the forearm.