The Radial Nerve - Nerve Imaging Atlas


	Head and Neck

	Vagus (X)

	Spinal Accessory Nerve (XI)

	Cervical Plexus (C2-4)

	Brachial Plexus (C5-T1)

	Upper Extremity

	Musculocutaneous

	Radial

	Median

	Ulnar

	Lower Extremity

	Ilioinguinal / Iliohypogastric

	Femoral

	Sciatic

	Common Peroneal

	Tibial

	Sural

	The Radial Nerve The radial nerve arises from the posterior cord of the brachial plexus. The radial nerve innervates the extensor-supinator muscle group and provides sensory innervation to the posterior aspect of the elbow, forearm and hand. The Radial Nerve in the Arm (supine with arm abducted) The radial nerve leaves the axillary artery with the profunda brachii artery in the axilla to innervate the triceps muscle (Video 1.4 MB). The profunda brachii artery follows the radial nerve as it moves from the axillary artery towards the spiral groove of the humerus. Because the radial nerve travels in the spiral groove of the humerus it can be damaged with these fractures.

	(Roll cursor over image to see labels.) The radial nerve divides into its superficial and deep branches on the lateral side of the antecubital fossa (Video 980 KB). The radial nerve lies over the lateral epicondyle of the humerus.

	The Superficial Radial Nerve in the Forearm (supine with arm supinated) The superficial radial nerve joins the radial artery in the middle third of the forearm (Video 604 KB). The SRN joins and leaves the radial artery on its lateral side. The superficial radial nerve divides approximately 5 cm proximal to the styloid process of the radius.

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