Splenius Capitis, Gross Anatomy

Description

Posteriorly, the splenius capitis forms an oblique muscle sheet in the upper cervical region, lying deep to trapezius and spanning from the inferior half of the ligamentum nuchae and spinous processes of C7 to T3 or T4 toward the mastoid process and the lateral third of the superior nuchal line of the occipital bone. Its fibers run superolaterally from the midline, flanking the cervical spine, with the paired muscles creating a shallow V-shaped arrangement across the back of the neck. Inferior to this layer, the erector spinae mass continues along the thoracic spine, while the posterior shoulder contour is shaped by deltoid and the posterior arm by triceps brachii. Bony landmarks for orientation include the external occipital protuberance superiorly and the spinous processes along the midline. Splenius capitis matters because it is a primary landmark in posterior cervical dissection and in the surgical corridor for dorsal approaches to the upper cervical spine, where sequential reflection of trapezius and splenius capitis exposes semispinalis capitis and the deeper suboccipital region. Neck pain and cervicogenic headache often localize to the occipital attachment region, and trigger points in splenius capitis can refer pain toward the mastoid and temporal area, a pattern that helps separate myofascial pain from radicular symptoms. This is the muscle you want when teaching coupled motion: unilateral contraction rotates and laterally flexes the head to the same side, while bilateral contraction extends the head and neck. Clear. Direct. Use this artwork for gross anatomy courses covering the posterior neck, sports medicine and physical therapy teaching on cervical extensor dysfunction, or surgical and interventional pain publications that need accurate surface-to-deep layer relationships in the female posterior cervical musculature. It also suits patient-facing explanations of posterior neck strain when you need a named structure rather than a generic “neck muscle.” Anatomical accuracy verified by SciePro's Medical Advisory Board.