Anterior Perspective of the Superior Lateral Brachial Cutaneous Nerve

Description

Arising from the posterior cord of the brachial plexus (C5 to C6), the superior lateral brachial cutaneous nerve is traced in the anterior shoulder as it travels with the axillary nerve deep to the deltoid, then becomes superficial over the lateral aspect of the proximal arm. Proximally it sits inferior to the glenohumeral joint and lateral to the surgical neck of the humerus, with the scapula and adjacent thoracic cage providing bony orientation. Distally, its cutaneous branches fan across the skin over the deltoid region and lateral upper arm. Small caliber. Clear course. Clinically, this branch anchors sensory mapping for axillary nerve injury, the classic setting being anterior shoulder dislocation or a fracture at the surgical neck of the humerus, where patients report numbness over the regimental badge area. An anterior perspective also helps clarify how the nerve’s cutaneous territory relates to common injection sites and portal placement, since iatrogenic neurapraxia can occur when deltoid-splitting approaches stray too close to the nerve’s superficial emergence. For teaching, the relationship between fascicles, neurilemma, and downstream cutaneous innervation reads cleanly when the branch is isolated against the shoulder joint anatomy. Use this artwork in gross anatomy and neuroanatomy modules covering the brachial plexus, in orthopaedic or sports medicine texts discussing shoulder instability, and in procedural training materials for deltoid injections and arthroscopy portal planning in an adult male patient model. It also supports patient-facing explanations of sensory loss after axillary nerve traction injuries without oversimplifying the anatomy. Anatomical accuracy verified by SciePro's Medical Advisory Board.