Posterior Perspective of the Serratus Posterior Superior Muscle

Description

Posterior thoracic musculature is presented in a male, with the trapezius spanning from the external occipital protuberance and nuchal ligament inferiorly to the spinous processes of the upper thoracic vertebrae and laterally toward the acromion and scapular spine. Deep to the medial border of the scapula, the serratus posterior superior can be appreciated as a thin, quadrilateral sheet arising from the nuchal ligament and spinous processes of C7 to T3 and passing inferolaterally to the superior borders of ribs 2 through 5 near their angles. Portions of the posterior deltoid cap the shoulder laterally, while the scapulae are faintly discernible beneath the muscle planes. Layering matters. This posterior perspective helps clarify why serratus posterior superior is often misidentified in teaching labs and even in operative notes, since it lies deep to trapezius and rhomboids and blends with the thoracolumbar fascia and upper intercostal musculature at its costal insertions. Clinically, pain along the upper medial scapular border or posterior upper ribs is frequently attributed to rhomboid or trapezius strain, yet myofascial trigger points and referred pain from serratus posterior superior can mimic cervicothoracic radiculopathy; palpation and needle placement both depend on knowing the rib level and fiber direction. The view also supports discussion of its debated function as an accessory muscle of inspiration, with segmental innervation via the anterior rami of T2 to T5 (intercostal nerves). Use this image in gross anatomy and kinesiology curricula to teach posterior thoracic wall layers, scapulothoracic landmarks, and costovertebral level orientation. It also fits well in physiotherapy texts, trigger point atlases, and clinical handouts on upper back pain patterns and safe dry needling trajectories near the ribs and pleura. Anatomical accuracy verified by SciePro's Medical Advisory Board.