Radial Nerve

Description

Illustration of the suprascapular, axillary and radial nerves

Illustration of the superficial radial nerve

General

• Is one of the two terminal continuations of the posterior cord of the brachial plexus.
• It receives contributions from C5-T1 nerve roots.

Course

• The nerve arises in the axillary region, is located posterior to axillary artery.
• It exits the axilla via the triangular interval to enter the posterior compartment of the arm.
• The radial nerve then descends down the arm winding around the spiral groove of the humerus.
• It enters the forearm by travelling anterior to the lateral epicondyle of the humerus, through the cubital fossa.
• It divides into superficial and deep branches.

Muscular innervations

• Triceps Brachii
• Anconeus
• Brachioradialis
• Extensor Carpi Radialis Longus

Posterior Interosseous Nerve

• Deep branch of the radial nerve in the dorsal forearm
• Motor: Superficial Dorsal Compartment of the Forearm, Deep Dorsal Compartment of the Forearm
• Sensory: wrist joint, no cutaneous innervation

Sensory Branches

• Posterior Cutaneous Nerve of the Arm: innervates the posterior surface of the arm
• Inferior Lateral Cutaneous Nerve of the Arm: innervates the lateral aspect of the arm.
• Superficial Branch of the Radial Nerve: cutaneous sensation to the dorsal aspect of the hand, dorsal aspect of the first to third digits and the dorsal lateral aspect of the fourth finger.
• Posterior Cutaneous Branch of the Forearm: innervates the middle of the posterior forearm.

Vascular Supply

• Radial Artery

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Clinical Significance

• Mid Shaft Humerus Fracture
• Radial Nerve Injury
• Posterior Interosseous Nerve Syndrome
• Wartenbergs Syndrome

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See Also

• Forearm Anatomy
• Elbow Anatomy Main
• Nerve Anatomy Main

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