The Serratus Posterior Superior Muscle Viewed Posteriorly Under the Skin of a Male

Description

Running obliquely from the lower cervical and upper thoracic midline toward the upper ribs, the serratus posterior superior lies deep to trapezius and the rhomboid minor and major, its digitations fanning inferolaterally to the costal surfaces of ribs 2 to 5. Medially, its fibers arise from the spinous processes around C7 to T3 and the adjacent nuchal ligament, just lateral to the midline fascia overlying the erector spinae group. Superiorly the muscle approaches the levator scapulae near the superomedial scapular angle, while laterally it disappears beneath the scapular margin and the posterior axillary fold. Skin and superficial fascia remain draped over the region. Orientation is unmistakable. Palpation and injections around the upper thoracic wall often confuse serratus posterior superior with the overlying rhomboids, and this posterior under-skin perspective clarifies the layer plane that a clinician or dissector must respect. Myofascial pain over the upper back, sometimes described along the medial scapular border or toward the posterior ribs, frequently involves trigger points in rhomboid major, but serratus posterior superior can refer pain more laterally along the upper intercostal spaces, which matters when planning dry needling or local anesthetic infiltration. Surgeons approaching the posterior thorax for rib fixation or posterolateral thoracotomy also benefit from recognizing how these thin costal slips relate to the scapular stabilizers and the thoracodorsal fascia. Use this artwork in gross anatomy and kinesiology teaching for layered back dissections, in physiotherapy and sports medicine materials on scapulothoracic pain patterns, or in clinical atlases illustrating posterior thoracic wall injections and surface anatomy. It also reads well for examination prep content that tests muscle layers and rib attachments in the upper thorax. Anatomical accuracy verified by SciePro's Medical Advisory Board.