Splenius Cervicis Muscle

Description

Posterior cervical musculature is presented with the splenius cervicis identified as a paired, oblique muscle mass in the posterolateral neck, lying deep to trapezius and typically inferior and slightly medial to the broader splenius capitis. Fibers arise from the spinous processes of the upper thoracic vertebrae (classically T3 to T6) and course superolaterally to insert on the transverse processes of the upper cervical vertebrae (often C1 to C3 or C4), placing it lateral to the midline spinous processes and posterior to the cervical transverse processes. Medially, the semispinalis cervicis and spinalis cervicis form a deeper paraspinal column; laterally, the levator scapulae and posterior scalene occupy the lateral neck. Bony context from the clavicle and scapular spine frames the shoulder girdle under the cervical region. Clear landmarks. Functionally, the splenius cervicis extends the cervical spine bilaterally and contributes to ipsilateral rotation and lateral flexion when acting unilaterally, a pattern that helps explain common myofascial pain referral into the posterolateral neck and upper shoulder after sustained head-forward posture. Posterior cervical approaches, including exposure for C3 to C7 instrumentation, often require layered dissection through trapezius and the splenii before reaching the deeper transversospinalis group, so appreciating the fiber direction and depth relationships reduces unnecessary muscle stripping and postoperative axial neck pain. Use this asset in gross anatomy and musculoskeletal courses when teaching the posterior triangle, intrinsic back muscles, and the distinction between splenius capitis versus splenius cervicis based on insertion level and action. It also suits surgical atlases, physiotherapy manuals, and patient education materials on cervical strain, whiplash-associated disorders, and targeted rehabilitation of neck extensors and rotators. Anatomical accuracy verified by SciePro's Medical Advisory Board.