Which muscle protracts the scapula?

Which muscle protracts the scapula?

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

Answer: (B)

Scapular protraction happens when the shoulder blade is pulled forward along the rib cage. The serratus anterior is the primary muscle for this action: it originates on the upper ribs and inserts on the anterior aspect of the medial border of the scapula. When it contracts, it pulls the medial edge of the scapula forward and around the thoracic wall, spreading the shoulder blades apart and pressing them against the chest. This forward pull is exactly what defines protraction, especially during pushing movements. The other muscles listed mainly move the scapula in the opposite direction or stabilize it—trapezius and rhomboids tend to retract or stabilize the scapula, and pectoralis major acts on the humerus rather than primarily on the scapula.

Scapular protraction happens when the shoulder blade is pulled forward along the rib cage. The serratus anterior is the primary muscle for this action: it originates on the upper ribs and inserts on the anterior aspect of the medial border of the scapula. When it contracts, it pulls the medial edge of the scapula forward and around the thoracic wall, spreading the shoulder blades apart and pressing them against the chest. This forward pull is exactly what defines protraction, especially during pushing movements. The other muscles listed mainly move the scapula in the opposite direction or stabilize it—trapezius and rhomboids tend to retract or stabilize the scapula, and pectoralis major acts on the humerus rather than primarily on the scapula.