Radial Tunnel

canalis radialis (nervus)

The radial tunnel is the anatomical passage through which the deep branch of the radial nerve travels from the elbow to the posterior forearm, bounded by the brachioradialis and extensor carpi radialis longus laterally, the brachialis and biceps tendon medially, and the radiocapitellar joint floor. Its roof is formed by successive fascial structures including the fibrous bands anterior to the radial head, the radial recurrent artery fan (leash of Henry), the extensor carpi radialis brevis medial border, and the arcade of Frohse.

Region: Forearm

Clinical Relevance

Clinical Notes

The radial tunnel extends from the radiocapitellar joint to the distal edge of the supinator. Four sites of potential nerve compression exist within it: anterior fibrous bands, the leash of Henry (radial recurrent vessels), the ECRB medial edge, and the arcade of Frohse. Radial tunnel syndrome is a clinical diagnosis of pain localised 4-5 cm distal to the lateral epicondyle, distinguished from lateral epicondylitis by the location of tenderness. Decompression of all four sites is performed in surgical cases.

Pathology

Common Injuries & Conditions

Radial Tunnel Compression

Pain from nerve irritation within the radial tunnel producing lateral forearm aching that is worse with resisted supination and middle finger extension, often misdiagnosed as resistant lateral epicondylitis.