Learn All About The Cervical Spinal Nerves

The cervical spinal nerves or cervical nerves  are a group of 8 spinal nerves that are part of the eight vertebrae that arise from the spinal cord. These 8 vertebrae, which are known and numbered from C-1 to C-8, originate at the base of the skull.

If you want to know how they work and their main characteristics within the human anatomical system, keep reading. Here we inform you in detail, following the guidelines of the guide published by the National Institute of Neurological Disorders and Stroke.

The spinal or spinal nerves

The cervical spinal nerves encompass 8 of the spinal or spinal nerves. These, in turn, are a set of nerves (around 31 and 33) belonging to the somatic nervous system whose function is to innervate (transmit nervous stimuli) different parts of the body.

They are composed of a sensitive root and a motor root. The first type is the one that allows you to give sensitivity to the muscles it innervates. As for the motor roots, they get the muscles to contract automatically. Thanks to this composition, they reach their goal.

According to their classification, the spinal nerves (which include the cervical spinal nerves) are the following:

• 8 pairs of cervical nerves (C1-C8).
• 12 thoracic nerves (T1-T12).
• Coccygeal Nerve.
• 5 sacral nerves (S1-S5).
• 5 lumbar nerves (L1-L5).

Characteristics of the spinal nerves

All cervical spinal nerves (except C-1, which usually do not have a dorsal root) are associated with a dermatome ( skin area supplied by a spinal nerve).

As they belong to the group of spinal nerves, as the following article published by the Journal of Neurosciences explains , the cervical spinal nerves will share the same characteristics as the others. So they are also mixed nerves. That is, they are composed of both sensory and motor fibers.

On the other hand, each one of the divisions of the ventral rami, except the thoracic ones (T1 to T12), form several branches that are known as nerve plexuses. These plexuses appear in the cervical, brachial and lumbo sacral areas.

Also, within these interconnected branches, the fibers originating from the ventral branches intersect and redistribute themselves. So each resulting branch contains fibers from different spinal nerves.

In addition, those that come from each ventral branch travel to the periphery of the body by different routes. For this reason, each muscle in a limb will receive an innervation from more than one spinal nerve. As a consequence, if there is damage to one of the spinal cord segments or one of the roots, the limb does not have to be completely disabled.

The cervical spinal nerves

The ventral rami of the first four spinal nerves form the cervical plexus. Its branches are cutaneous nerves that transmit sensory impulses and innervate the skin in the following areas :

• Neck.
• Ear.
• Back of the head.
• Shoulder.

It must be said that there are also branches that supply the anterior neck muscles. From this cervical plexus, the phrenic nerve is born; which groups fibers that come from C-3 and C-4. This nerve runs through the chest to serve the diaphragm ; the most important muscle in respiration.

On the other hand, the ventral nerves of the cervical spinal nerves C-5 and C-8 (together with the anterior primary branch of T-1) form the brachial plexus. Its ramifications are responsible for the innervation of the shoulders and upper extremities.

Finally, the dorsal branches are responsible for the innervation of the cervical facets (joints between the vertebrae). Ramifications of the muscles of the head and neck also arise from these branches ; as well as the skin between the vertex (upper surface of the head) and the shoulders.

Division of the cervical spinal nerves

Like other spinal nerves, specialists point out that the cervical spinal nerves divide into dorsal and ventral branches after leaving the spinal canal. As they exit the spinal cord, the ventral and dorsal roots join to form the spinal or dorsal root ganglion.

These nodes are then divided into:

• Ventral or anterior bouquet: it is a thick bouquet. It intersects, divides, and joins with the anterior rami of other spinal nerves to form the cervical plexus.
• Dorsal or posterior branch: it is the posterior branch of the common trunk. It is a much thinner branch than the previous branch.

Learning is power, and more when it comes to your own body

It is crucial to know each of the areas that make up the human body; since they are the base where many common ailments are sheltered. And, as you have well seen, the cervical nerves are a part of the nervous system that, without a doubt, should be taken into account.

To do this, make sure to make regular visits to the doctor in order to rule out any type of problem.