0 one of the three muscles of the main part of the body. It is shaped like a saw (= a long cutting tool with points along one edge) and starts in the spine or the ribs. --
Stretching from the spine to the scapula, rhomboid major forms part of the latter group together with rhomboid minor, serratus anterior, levator scapulae, and trapezius.
In the upper body the serratus anterior works eccentrically to prevent winging of the scapula.
Other muscles that perform this function include the serratus anterior and pectoralis minor.
The long thoracic nerve travels inferiorly on the surface of the serratus.
The serratus anterior formed the basal unit for these three muscles.
This may require concerted professional help to re-educate the muscles and re-engage muscle action in the serratus anterior during such movements.
It supplies branches to the first and second intercostal spaces as well as to the superior portion of serratus anterior.
Antagonists to this function (upward rotators of the scapulae) are the serratus anterior and upper and lower fibers of the trapezius.