Cervical nerves

• Cervical nerves are spinal nerves that originate in the spinal cord of the neck.
• The cervical nerves supply the neck, and upper extremities.
• The cervical nerves form a nexus of nerves called brachial plexus.

Cervical and vagus nerve and carotid artery

Total of 8 cervical nerves

Although there are seven cervical vertebrae (C1-C7), there are a total of eight cervical nerves C1–C8.

C1–C7 emerge above their corresponding vertebrae, while C8 emerges below the C7 vertebra. Elsewhere in the spine, the nerve emerges below the vertebra with the same name.

• The posterior distribution includes the suboccipital nerve (C1), the greater occipital nerve (C2) and the third occipital nerve (C3). The anterior distribution includes the cervical plexus (C1-C4) and brachial plexus (C5-T1).
• The cervical nerves innervate the sternohyoid, sternothyroid and omohyoid muscles.
• A loop of nerves called ansa cervicalis is part of the cervical plexus.

Anatomy

• Each spinal nerve is connected to the spinal cord by a dorsal root and a ventral root.
• The cell bodies of the sensory neurons are in the dorsal root ganglion, but the motor neuron cell bodies are in the gray matter.
• The two roots join to form the spinal nerve just before the nerve leaves the vertebral column.
• Because all spinal nerves have both sensory and motor components, they are all mixed nerves.