Splenius Capitis, Posterior View

Description

Seen from the posterior aspect of an adult male, the splenius capitis forms a paired, obliquely oriented sheet across the posterolateral neck, spanning from the upper thoracic midline to the mastoid region of the temporal bone and adjacent lateral superior nuchal line. Medially, its fibers arise from the ligamentum nuchae and spinous processes (classically C7 to T3 or T4), then course superolaterally to lie deep to trapezius and superficial to semispinalis capitis. Superiorly it approaches the occipital bone and lateral skull base, while inferiorly it blends toward the cervicothoracic junction. A broad surface muscle. Functionally, the splenius capitis is a principal landmark when teaching posterior cervical muscle layering and when planning posterior approaches to the upper cervical spine, because it must be reflected to reach the deeper transversospinales group. Unilateral contraction rotates and laterally flexes the head to the same side, whereas bilateral activation extends the head and neck, a pattern often implicated in cervicogenic headache and posture-related myofascial pain with tenderness near the mastoid insertion. Its relationship to the greater occipital nerve (emerging inferior to the obliquus capitis inferior and then piercing semispinalis capitis) also matters clinically: superficial dissection planes that respect the splenius and semispinalis layers help explain entrapment patterns in occipital neuralgia. Use this posterior view in gross anatomy and kinesiology teaching to anchor the transition from superficial trapezius to the intermediate splenius layer and then to semispinalis capitis during back and neck dissections. It also suits surgical education materials discussing posterior cervical exposure, trigger point mapping, and clinic-facing diagrams for neck pain counseling where muscle actions and attachments must be anatomically consistent. Anatomical accuracy verified by SciePro's Medical Advisory Board.