Which nerves innervate the splenius capitis?

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

Answer: (B)

Splenius capitis is part of the deep back muscles that move and stabilize the head, and it receives motor innervation from the posterior (dorsal) rami of the cervical spinal nerves. These dorsal rami supply the intrinsic back muscles, including the splenius group, and provide sensory input to the skin over the back.

In contrast, the ventral rami of the cervical nerves mostly innervate the limbs and the anterior/lateral trunk, not the splenius capitis. The dorsal rami of the thoracic nerves would target thoracic back muscles, not the neck muscle here. The spinal accessory nerve innervates the sternocleidomastoid and trapezius, not splenius capitis.