Terminal Branches of the Brachial Plexus

Question 1

What are the 5 branches of the brachial plexus, their comparments and their nerve innovation?

Answer 1

Musculocutaneous (C5-C7), anterior
Axillary (C5, C6), posterior
Median (C6-T1), anterior
Radial (C5-T1), posterior,
Ulnar (C8-T1), anterior

Question 2

Musculocutaneous

Answer 2

Anterior Compartment of the Arm
Coracobrachalis, Biceps Brachii, brachialis

Sensory: supplies elbow, then branches as lateral antebrachial cutaneous and innervates skin of lateral forearm

Question 3

Axillary

Answer 3

Shoulder
Teres Minor, Deltoid

Sensory: skin of upper lateral arm, GHJ, acriomioclavicular joint

Question 4

Median

Answer 4

Anterior Compartment of the forearm
Becomes anterior interosseous
Superficial Layer - Median Nerve (except for FCU)
Intermediate Layer - Median Nerve
Deep Layer - Anterior Interosseous (exception; FDP, which is only 1/2 anterior interosseous)
Also branches as recurrent branch of median nerve, which supplies some hand muscles

Sensory - Skin of lateral 3.5 fingers and palm, wrist, proximal and distal radioulnar joints

Question 5

Radial

Answer 5

Posterior Compartment of forearm and arm
Arm (triceps and anconeous) - Radial
Superficial Forearm (Brachioradialis/ECRL) - Radial
Superficial Forearm (ECRB) - Deep radial
Deep Forearm (Supinator, pierces) - Deep radial
Deep Forearm - Posterior interosseous

Sensory: Skin of lower lateral arm, skin of posterior arm and forearm, skin of lateral dorsal aspect of hand, elbow joint, wrist, proximal and distal radioulnar joints

Question 6

Ulnar

Answer 6

Anterior Compartment
Pierces (and innervates) flexor carpi ulnaris
Travels between FCU and FDP (innervates 1/2 of) until it reaches the hand, where is supplies more muscles as the deep branch of ulnar nerve.

Sensory: Skin of medial medial 1.5 fingers, elbow and wrist joints