Corpus: Scalenus posterior muscle

The posterior scalene muscle is a skeletal muscle belonging to the neck musculature.

The origin of the posterior scalene muscle is the posterior tuberosity of the transverse processes of cervical vertebrae 5 and 6. It attaches to the outer surface of the 2nd rib, occasionally also to the 3rd rib.

The posterior scalene muscle is innervated by the anterior branches of the spinal nerves from the spinal cord segments C7 and C8.

When contracting on both sides, the posterior scalene muscle raises the 2nd and 3rd ribs and thus increases the thoracic volume. The posterior scalene muscle thus acts primarily as an auxiliary respiratory muscle. When contracted on one side, the muscle can slightly tilt the cervical spine.

See also: Scalene gap