Master Dermatomes - Cervical with Picmonic for Physician Assistant

C3, the third cervical spinal nerve, innervates the skin to have sensation in a "high turtleneck" pattern around the neck.

Cervical nerve 4 (C4), innervates the skin near the neck in a "low collar shirt" distribution. Its control of the thoracic diaphragm has inspired a medical mnemonic: "Cut C4, breathe no more."

The cervical spinal nerve 5 (C5) is responsible for innervating the anterolateral shoulder skin and sensation pathways.

The cervical spinal nerve 6 (C6) is responsible for sensation and skin innervation of the thumb and posterolateral arm.

C7 innervates skin and sensation of the posterior arm to the middle and pointer fingers.

The C8 nerve receives sensory afferents from the C8 dermatome. This consists of all the skin on the little finger, and continuing up slightly past the wrist on the palmar and dorsal aspects of the hand and forearm. Clinically, a test of the pad of the little finger is often used to assess C8 integrity.