Which muscle group is primarily involved in scapular downward rotation?

The muscle group primarily involved in scapular downward rotation is indeed the rhomboids, levator scapulae, and pectoralis minor. Each of these muscles plays a significant role in controlling and facilitating the movement of the scapula during downward rotation.

The rhomboids, which include the rhomboid major and rhomboid minor, are located between the scapulae and vertebral column. They are responsible for drawing the scapulae together and down, thus playing a key role in downward rotation.

The levator scapulae assists in elevating the scapula and also aids in its downward rotation. This muscle originates from the cervical vertebrae and attaches to the superior portion of the scapula, influencing the scapular position.

Pectoralis minor works by pulling the scapula down and forward against the rib cage, contributing significantly to the downward rotation when it contracts. Its action complements that of the rhomboids and levator scap, providing a coordinated movement towards scapular downward rotation.

The other groups of muscles listed would not contribute as directly to this particular action. Thus, the collective actions of the rhomboids, levator scapulae, and pectoralis minor clearly define the scapular downward rotation, confirming that