Semispinalis cervicis is the largest cervical extensor, spanning from the upper thoracic transverse processes to the mid-cervical spinous processes. It is larger than the semispinalis capitis in the mid-cervical region.
| Origin | Transverse processes of T1-T6 |
|---|---|
| Insertion | Spinous processes of C2-C5 — spanning 5-6 levels |
| Nerve Supply | Dorsal rami of cervical spinal nerves |
| Blood Supply | Occipital and vertebral artery branches |
| Actions | Extends the cervical spine — the primary cervical extensor; Contralateral cervical rotation |
|---|
Semispinalis cervicis is the primary target of suboccipital and cervical paraspinal trigger point injections for cervicogenic headache. Its denervation from posterior cervical surgery is a significant contributor to post-laminectomy cervical kyphosis.
Palpated as the dominant bilateral cervical extensor mass lateral to the spinous processes.
Loss of semispinalis cervicis function after posterior cervical laminectomy contributing to progressive cervical kyphotic deformity (swan neck deformity).
