Which muscle is innervated by the dorsal scapular nerve?

Which muscle is innervated by the dorsal scapular nerve?

• A. Levator scapulae
• B. Serratus posterior superior
• C. Serratus posterior inferior
• D. Trapezius

Answer: (A)

Dorsal scapular nerve mainly supplies muscles that elevate and stabilize the scapula, with the levator scapulae being a primary target. Levator scapulae originates from the transverse processes of C1–C4 and inserts on the superior angle and medial border of the scapula; its main action is to elevate the scapula and assist in downward rotation of the scapular glenoid cavity. The dorsal scapular nerve typically carries fibers from C5 (often with C4) to innervate this muscle. Serratus posterior superior and serratus posterior inferior are innervated by intercostal nerves (ventral rami of the thoracic nerves), not the dorsal scapular nerve. The trapezius is innervated by the spinal accessory nerve (CN XI), not by the dorsal scapular nerve.

Dorsal scapular nerve mainly supplies muscles that elevate and stabilize the scapula, with the levator scapulae being a primary target. Levator scapulae originates from the transverse processes of C1–C4 and inserts on the superior angle and medial border of the scapula; its main action is to elevate the scapula and assist in downward rotation of the scapular glenoid cavity. The dorsal scapular nerve typically carries fibers from C5 (often with C4) to innervate this muscle.

Serratus posterior superior and serratus posterior inferior are innervated by intercostal nerves (ventral rami of the thoracic nerves), not the dorsal scapular nerve. The trapezius is innervated by the spinal accessory nerve (CN XI), not by the dorsal scapular nerve.