Which of the following actions is performed by the rhomboid major?

The rhomboid major primarily functions to retract the scapula, drawing it closer to the spine. This action is crucial for stabilizing the shoulder girdle during various movements and enhancing overall postural alignment. Additionally, the rhomboid major contributes to the downward rotation of the scapula, helping to position the glenoid cavity to facilitate arm movements. This dual action of retraction and downward rotation is vital for effective upper limb mechanics, particularly during activities such as pulling or rowing.

The actions associated with the other options involve different muscle groups. Scapula elevation and upward rotation are primarily performed by the upper trapezius and serratus anterior. Scapula depression and lateral rotation do not pertain to the rhomboid major’s role, as these actions are carried out by muscles like the lower trapezius and serratus anterior, respectively. Lastly, scapula flexion and extension are not applicable movements since the scapula itself does not perform flexion or extension; rather, these terms are typically associated with limb movements.

Understanding these specific actions of the rhomboid major helps clarify its importance in stabilizing and positioning the shoulder for optimal function.