Which nerve innervates both rhomboid major and rhomboid minor?

Which nerve innervates both rhomboid major and rhomboid minor?

• A. Axillary nerve
• B. Dorsal scapular nerve (C4-C5)
• C. Thoracodorsal nerve
• D. Spinal accessory nerve

Answer: (B)

The rhomboid major and rhomboid minor are innervated by the dorsal scapular nerve, which most often arises from the C5 spinal nerve (sometimes with C4). This nerve travels to the deep surface of the rhomboids and provides their motor input, enabling these muscles to retract the scapula and help downwardly rotate the scapulothoracic joint while keeping the shoulder girdle stable. That’s why this nerve is the correct answer: it specifically supplies the rhomboid muscles. The other nerves target different muscles—axillary nerve to the deltoid and teres minor, thoracodorsal to latissimus dorsi, and the spinal accessory nerve to trapezius and sternocleidomastoid—so they don’t innervate the rhomboids.

The rhomboid major and rhomboid minor are innervated by the dorsal scapular nerve, which most often arises from the C5 spinal nerve (sometimes with C4). This nerve travels to the deep surface of the rhomboids and provides their motor input, enabling these muscles to retract the scapula and help downwardly rotate the scapulothoracic joint while keeping the shoulder girdle stable. That’s why this nerve is the correct answer: it specifically supplies the rhomboid muscles. The other nerves target different muscles—axillary nerve to the deltoid and teres minor, thoracodorsal to latissimus dorsi, and the spinal accessory nerve to trapezius and sternocleidomastoid—so they don’t innervate the rhomboids.