Serratus posterior superior muscle

The serratus posterior superior muscle is a muscle in the back that connects the upper part of the spinal column to several ribs and assists with breathing in, especially when done forcefully.

Origin
The serratus posterior superior originates at three vertebrae in the upper back. It attaches to the spinous processes of C7-T2 and the supraspinous ligament above those vertebrae.

Insertion
The serratus posterior superior inserts at four of the upper ribs. It attaches to the posterior aspect of the second through fifth ribs.

Innervation
The serratus posterior superior is innervated by the anterior primary rami (T2-T5).

Word origin

 * Serratus means saw tooth, in the same way as in serrated knife, referring to the back-and-forth pattern the muscle makes as it attaches to each rib.
 *  Posterior , meaning on the back side, distinguishes it from the serratus anterior muscle - a similar muscle on the front side of the rib cage.
 * Superior distinguishes it from the serratus posterior inferior muscle, which sits below it.