Corpus: Obliquus capitis inferior muscle

The obliquus capitis inferior muscle is a skeletal muscle located in the neck and is part of the autochthonous back musculature.

The obliquus capitis inferior muscle originates from the spinous process of the axis (the 2nd cervical vertebra). It follows an oblique upward course to attach to the transverse process of the atlas (the 1st cervical vertebra).

This muscle is innervated by lateral branches of the posterior rami of the spinal nerves from segments C1 and C2. The dorsal ramus of the first spinal nerve is specifically known as the suboccipital nerve.

The obliquus capitis inferior muscle functions to rotate the atlas (and consequently the head) to the same side when contracted unilaterally, affecting the movement of the atlantooccipital joint.