Posterior Antebrachial Cutaneous Nerve, Posterior View

Description

Running distally on the posterior aspect of the arm and forearm, the posterior antebrachial cutaneous nerve is traced from its origin as a branch of the radial nerve in the posterior compartment of the arm toward the dorsolateral forearm. Proximally, it lies deep to the triceps brachii and then becomes subcutaneous as it passes inferior to the lateral epicondyle region, where it travels along the posterior border of the brachioradialis and over the extensor carpi radialis longus and brevis. Near the distal third of the forearm, multiple filaments fan out superficially toward the skin near the wrist, in close relationship to the extensor retinaculum and the extensor tendon groups on the dorsum of the hand. Clinically, this nerve matters because it is a frequent culprit in posterolateral forearm dysesthesia after lateral elbow surgery and after trauma around the lateral epicondyle. Its superficial course makes it susceptible to iatrogenic injury during approaches for lateral epicondylitis procedures, radial head exposure, and distal humerus fixation, where small branches can be transected or tethered by scar. The branching pattern at the distal forearm also helps distinguish posterior antebrachial cutaneous territory from the superficial radial nerve distribution when you are mapping sensory symptoms around the dorsal wrist and hand. Anatomy faculty can slot this posterior view into upper limb neuroanatomy and dissection-lab orientation to reinforce how a named cutaneous nerve leaves the deep fascia and becomes purely sensory distally. It also fits cleanly into orthopedic and plastic surgery teaching files for lateral elbow and dorsal forearm approaches, and into textbook figures discussing radial nerve branching and postoperative sensory complications. Anatomical accuracy verified by SciePro's Medical Advisory Board.