Rectus capitis posterior major

The rectus capitis posterior major (Latin: musculus rectus capitis posterior major) is a small paired triangular-shaped muscle of the neck. It is situated in the posterior compartment of the neck. Therefore, the rectus capitis posterior major is known as one of the posterior neck muscles. This muscle forms the deepest layer of the group. As the rectus capitis posterior major is located below the occipital bone of the skull, it is classified as the suboccipital muscle. It acts at the atlanto-occipital joint.

Origin

The rectus capitis posterior major muscle originates from the spinous process of the axis (C2).

Insertion

The rectus capitis posterior major inserts on the lateral aspect of the inferior nuchal line of the occipital bone.

Action

The main movements provided by the rectus capitis posterior major muscle are rotation of the head to the ipsilateral side (unilateral contractions) and extension of the head (bilateral contractions).

Innervation

The rectus capitis posterior major is innervated by the posterior ramus of the 1st cervical spinal nerve (C1), also known as the suboccipital nerve.

Blood supply

The rectus capitis posterior major muscle receives arterial blood supply from the branches of the vertebral and occipital arteries.