The radial nerve (C5, C6, C7, C8, and T1) arises from the posterior cord at the level of the coracoid process , posterior to the axillary artery and lateral cord . It exits the axilla towards the posterior arm through the lower triangular space (triangular interval ) bound by the teres major cranially, the long head of triceps medially, and the humerus laterally. The triceps branches come off the radial nerve high in the axilla. The nerve then courses in the posterior arm, in the spiral groove along with the profunda brachii vessels. It then enters the anterior compartment of the arm between the biceps brachii and triceps and then between the biceps brachii and brachioradialis . It gives off the brachioradialis, extensor carpi radialis longus and brevis (ECRL and ECRB) branches, and the posterior interosseous nerve (PIN ) and then continues as the superficial radial nerve (pure cutaneous). The PIN courses through the supinator muscle (arcade of Fröhse ) and supplies the remaining muscles of the posterior forearm. The superficial radial nerve emerges from under the brachioradialis tendon and supplies the skin of the dorsum of the hand laterally as well as the dorsum of the lateral three and a half fingers up to the middle phalanx.

Supplementary material

Video 7.1

(MP4 1181601 kb)


  1. 1.
    Kinni V, Craig J, van Holsbeeck M, Ditmars D (2009) Entrapment of the posterior interosseous nerve at the arcade of Frohse with sonographic, magnetic resonance imaging, and intraoperative confirmation. J Ultrasound Med 28(6):807–812PubMedGoogle Scholar
  2. 2.
    Loizides A, Peer S, Ostermann S, Henninger B, Stampfer-Kountchev M, Gruber H (2011) Unusual functional compression of the deep branch of the radial nerve by a vascular branch (leash of Henry): ultrasonographic appearance. Rofo 183(2):163–166CrossRefPubMedGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Amgad S. Hanna
    • 1
  1. 1.Department of NeurosurgeryUniversity of WisconsinMadisonUSA

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