Radial Nerve|Upper Limbs|Anatomy

 RADIAL NERVE

The radial nerve is the thickest and largest nerve of the upper limb.

ROOT VALUE

Ventral rami of C5, C6, C7, C8 and T1

ORIGIN COURSE & RELATIONS

The course and branches of the radial nerve, which passes through three regions of the arm: axilla, radial groove on the back of the arm, and front of the forearm.

Axilla: In axilla the radial nerve lies against the muscles forming the posterior wall of the axilla, and it gives two muscular branches to supply the long and medial heads of triceps and one cutaneous branch.

Radial Groove : In the radial groove it gives three muscular branches to supply the long and medial heads of triceps and anconeus and two cutaneous branches.

Arm: On the front of the arm, the radial nerve lies between brachialis on the medial side and brachioradialis and extensor carpi radialis longus on the lateral side.

Forearm: In the forearm, the radial nerve divides into two terminal branches: the deep terminal branch (posterior interosseous nerve) and the superficial terminal branch (superficial radial nerve).

Deep Terminal Branch: The deep terminal branch supplies several muscles in the forearm and ends in a pseudoganglion at the back of the wrist, which supplies the wrist and distal radioulnar joints.

Superficial Terminal Branch: The superficial terminal branch runs on the lateral side of the front of the forearm and divides into four or five digital branches, which supply the skin of the lateral half of the dorsum of the hand and lateral 2 1/2 digits till their distal interphalangeal joints.

APPLIED ANATOMY