Nerve
Musculocutaneous nerve
Anterior arm and lateral forearm skin
High-yield
Pierces coracobrachialis; supplies BBC (Biceps, Brachialis, Coracobrachialis). Injury weakens elbow flexion and supination.
Overview
A terminal branch of the lateral cord that supplies the anterior arm flexors and continues as the lateral cutaneous nerve of the forearm.
Learning this group? Read How to learn the brachial plexus.
Reference facts
- Roots
- C5, C6, C7 (lateral cord)
- Course
- Pierces coracobrachialis, runs between biceps brachii and brachialis, then emerges laterally as the lateral cutaneous nerve of the forearm
- Motor
- Coracobrachialis, biceps brachii, brachialis (anterior arm compartment)
- Sensory
- Lateral surface of the forearm (lateral antebrachial cutaneous nerve)
Frequently asked questions
What are the roots of the musculocutaneous nerve?
The musculocutaneous nerve arises from C5, C6, C7 (lateral cord).
What muscles does the musculocutaneous nerve supply?
The musculocutaneous nerve supplies the coracobrachialis, biceps brachii, brachialis (anterior arm compartment).
What is the sensory distribution of the musculocutaneous nerve?
The musculocutaneous nerve carries sensation from the lateral surface of the forearm (lateral antebrachial cutaneous nerve).
What is the course of the musculocutaneous nerve?
Pierces coracobrachialis, runs between biceps brachii and brachialis, then emerges laterally as the lateral cutaneous nerve of the forearm.