The Splenius capitis muscle is located in the back or the neck. It originates on the ligamentum nuchae and the spinous processes of C7 to T6. It attaches to the occipital bone and the mastoid process of the temporal bone. This muscle functions bilaterally to produce neck extension, and unilaterally to produce rotation of the head to the same side. When trigger points develop in this muscle they will produce restriction in neck movement, as well as pain felt in the neck, but also strongly in the top of the head. Trigger points in this muscle are a common cause of headaches.