Muscles of the vertebral column: Head movements and trunk extension
innervation of sternocleidomastoid
Accessory nerve (XI)
innervation of scalenes muscles
Anterior rami of cervical spinal nerves
innervation of splenius capitis
Posterior rami cervical spinal nerves
innervation of quadratus lumborum
anterior rami of lumbar spinal nerves
Quadratus lumborum: Action
each flexes vertebral column laterally
Semispinalis capitis: Action
extend vertebral column and head
Quadratus lumborum: Origin
iliac crest
Quadratus lumborum: Insertion
inferior border of last rib (12th) & transverse processes of lumbar vertebrae
Erector spinae: Action
maintain posture, extends, and bends the vertebral column laterally; longissimus also extends and rotates the head
Sternocleidomastoid : Origin
manubrium of sternum and medial portion of clavicle
Semispinalis capitis: Insertion
occipital bone and spinous processes of cervical vertebrae and T1-T4
innervation of semispinalis
posterior rami of cervical and thoracic spinal nerves
innervation of erector spinae
posterior rami of cervical to lumbar spinal nerves
Splenius capitis: Origin
spinous processes of C7-T6
Semispinalis capitis: Origin
transverse processes of C7-T12
Scalenes (anterior, middle, posterior): Origin
transverse processes of cervical vertebrae
Erector spine: Origin
various sites; cervical, thoracic, and lumbar vertebrae, ribs, and sacrum
Erector spinae: Insertion
various sites; occipital bone, mastoid process, cervical and thoracic vertebrae