Which muscles are involved in scapula downward rotation?

Scapula downward rotation is primarily achieved through the coordinated action of several key muscles, including the rhomboids, levator scapulae, and pectoralis minor.

The rhomboids, originating from the spinous processes of the thoracic vertebrae and inserting on the medial border of the scapula, play a crucial role in downward rotation by retracting the scapula and assisting in tilting it downward. The levator scapulae, which connects the cervical vertebrae to the scapula, also assists in elevating the medial border of the scapula, contributing to downward rotation. Pectoralis minor, located beneath the pectoralis major, facilitates downward rotation primarily by anchoring the scapula and pulling it anteriorly and inferiorly.

The other muscle groups mentioned, while involved in movement and stabilization of the scapula, do not primarily contribute to downward rotation. This distinction is essential for understanding shoulder biomechanics, particularly in rehabilitation and exercise strategies aimed at optimizing scapular movements.