The splenius capitis muscle is located on the posterior neck, deep to the trapezius. It has a broad origin on the nuchal ligament and spinous processes of the lower cervical and upper thoracic vertebrae. The muscle fibers extend superiorly and laterally from the spine to the base of the skull, and the insertion is strong and thick on the mastoid process of the temporal bone and lateral occiput. The strap-like fibers of the splenius capitis are most superficial near the top of the posterior triangle of the neck between the sternocleidomastoid and upper trapezius. The entire muscle may be palpated when the overlying trapezius and rhomboid are relaxed.
Together, the splenius capitis and sternocleidomastoid form an inverted “V” on the lateral neck. The sternocleidomastoid extends anteriorly from the mastoid process to the sternum and medial clavicle, while the splenius capitis extends posteriorly to the spinous processes. Posturally, this muscular “V” centers the head front to back over the trunk and shoulder girdle. Together, the right and left sides help center the head from side to side, front to back, and rotationally. These two muscles also strongly pull the head to one side or the other when activated unilaterally.
The splenius capitis is large and broad, making it an effective prime mover for extension, lateral flexion, and rotation of the head and neck. It has all the same actions as the splenius cervicis, but attaches more laterally and superiorly, giving it better leverage for lateral flexion and rotation. The splenius capitis, splenius cervicis, and levator scapulae combine efforts to rotate the head to the same side and oppose the rotational efforts of the trapezius, sternocleidomastoid, and anterior scalene. Balanced mobility and activation of these muscles is critical to optimal cervical alignment, range of motion, and head posture. Tension headaches are often the result of forward head posture and associated hypertonicity in the splenius capitis, splenius cervicis, and sternocleidomastoid.
Splenius Capitis
Attachments
• Origin: Nuchal ligament and spinous processes of C7–T3
• Insertion: Mastoid process of temporal bone and lateral portion of superior nuchal line of the occiput
Actions
• Extends head and neck (bilateral action)
• Laterally flexes head and neck (unilateral action)
• Rotates head and neck toward same side (unilateral action)
Innervation
• Dorsal rami of cervical spinal nerves
Client Homework—
Child’s Pose with Head Rotation
1.
Kneel on the floor with knees about shoulder width apart.
2.
Place palms on the floor about shoulder width apart.
3.
Exhale, sit back on your heels, and lower your chest toward the floor.
4.
Relax your neck, shoulders, and arms, elongate the spine, and let your head rest forward.
5.
Pull your arms in toward your knees and gently turn your head to one side to increase the neck stretch.
6.
Repeat on the other side by turning your head to the other side.
Editor’s note: The Client Homework element in Functional Anatomy is intended as a take-home resource for clients experiencing issues with the profiled muscle. The stretches identified in Functional Anatomy should not be performed within massage sessions or progressed by massage therapists, in order to comply with state laws and maintain scope of practice.
Christy Cael is a licensed massage therapist and certified strength and conditioning specialist. Her private practice focuses on injury treatment, biomechanical analysis, craniosacral therapy, and massage for clients with neurological issues. She is the author of Functional Anatomy: Musculoskeletal Anatomy, Kinesiology, and Palpation for Manual Therapists (Lippincott Williams & Wilkins, 2009). Contact her at functionalbook@hotmail.com.