Downward rotation of the scapula is primarily produced by which muscles?

• A. Levator scapulae, rhomboids, pectoralis minor
• B. Trapezius (upper and lower), serratus anterior
• C. Serratus anterior
• D. Rhomboids only

Answer: (A)

Downward rotation of the scapula happens when the scapula is pulled so the glenoid fossa tilts downward. This action is produced mainly by the combined pull of levator scapulae, rhomboids, and pectoralis minor, which retract the scapula and depress or tilt it to rotate downward. The rhomboids pull the medial border toward the spine and rotate the scapula downward; levator scapulae helps tilt the superior angle and contributes to downward rotation when the arm is fixed; pectoralis minor depresses and anteriorly tilts the scapula via the coracoid, aiding downward rotation. The serratus anterior and parts of the trapezius are the primary upward rotators, so they aren’t the best fit for this motion.