Which muscle is primarily responsible for elevating the scapula and upwardly rotating the scapula?

• A. Trapezius
• B. Pectoralis minor
• C. Rhomboids
• D. Serratus anterior

Answer: (A)

Elevating the scapula is done mainly by the upper fibers of the trapezius, and upward rotation of the scapula involves a coordinated action where the trapezius (upper and lower fibers) works with the serratus anterior. Among a single muscle, the trapezius best fits both actions: its upper fibers lift the scapula, and its lower fibers contribute to upward rotation as the scapula tilts and rotates upward during arm elevation. The serratus anterior does upward rotation strongly but does not elevate the scapula, so it isn’t the primary muscle for both movements. The rhomboids retract and downwardly rotate; pectoralis minor depresses and downwardly rotates. Therefore, the trapezius is the best answer for both elevating and upwardly rotating the scapula.