Which nerve supplies Splenius cervicis?

• A. Dorsal rami spinal nerves
• B. Ventral rami of cervical nerves
• C. Phrenic nerve
• D. Spinal accessory nerve

Answer: (A)

Splenius cervicis is an intrinsic back muscle that receives its nerve supply from the dorsal primary rami of the spinal nerves. These posterior rami specifically innervate the deep back muscles, including the splenius group, and carry sensory fibers to the skin of the back in that region. The ventral rami supply most of the anterior and lateral neck muscles and the limbs, not this muscle. The phrenic nerve goes to the diaphragm, and the spinal accessory nerve mainly innervates trapezius and sternocleidomastoid. Therefore, the nerve supplying splenius cervicis is the dorsal rami of the spinal nerves.