Anatomical Structure and Location of the Long Thoracic Nerve

Description

Arising from the anterior rami of C5, C6, and C7, the long thoracic nerve is traced as it descends in the posterior triangle of the neck and then courses inferiorly along the lateral thoracic wall. Proximally, its roots lie deep to the sternocleidomastoid and adjacent to the brachial plexus trunks, while the nerve itself passes posterior to the clavicle and travels on the superficial surface of the serratus anterior, lateral to the rib cage. Neighboring landmarks in the neck and shoulder region logically include the trapezius, levator scapulae, and the scalene muscles, with the subclavian and axillary vessels positioned anteroinferior to the plexus elements. Course matters here. The long thoracic nerve’s long, relatively unprotected path makes it a frequent casualty during axillary surgery and chest wall procedures, including sentinel lymph node biopsy and mastectomy, and it can also be injured by traction in sports or by blunt trauma. Denervation of serratus anterior produces medial scapular winging and impaired upward rotation, a functional deficit that helps distinguish long thoracic neuropathy from spinal accessory nerve injury, where trapezius wasting and shoulder droop dominate. Use this artwork for teaching brachial plexus organization beyond the classic cords and branches, with emphasis on roots, relations to the scalene interval, and the transition from neck to axilla in gross anatomy labs. It also fits operative anatomy figures for breast and axillary surgery texts, physical therapy education on scapulothoracic mechanics, and clinical handouts explaining serratus anterior palsy and winged scapula on examination. Anatomical accuracy verified by SciePro's Medical Advisory Board.