Cervical Plexus
The cervical plexus is a conglomeration of cervical nerves formed by the anterior rami of
spinal nerves C1-C4. These are the roots (limbs) of the cervical plexus.
The 5th cervical nerve may also be considered as part of the plexus due to its contribution
in the formation of one of the motor branches of the cervical plexus, the phrenic nerve.
Therefore, the cervical plexus can also be defined as a network of nerves formed by the
anterior rami of spinal nerves C1 – C5 that gives off both motor (deep) and sensory
(superficial) branches.
FORMATION
The cervical plexus is formed in the neck region. It lies deep to the sternocleidomastoid
muscle, and anterolateral to the levator scapulae. Each of the cervical nerves forming the
plexus communicates with one another in a superior-inferior fashion close to their origins,
thus C2 accepts communicating fibres from C1, C3 from C2, and so on. These
communicating fibres are the contributions from the sympathetic trunk (sympathetic
nervous system) to the cervical plexus and are known as the “gray rami” communicantes
(meaning blood vessel accompanied). They descend from
the superior cervical ganglion (which is the largest of the
three cervical ganglia).
Each of the cervical nerves (except the first, C1) then divide
into two branches: an ascending branch and a descending
branch. They subsequently unite with branches of adjacent
cervical nerves to form loops. Loops and branches from the
cervical nerves contribute to the formation of the cervical
plexus.
The cervical plexus is a conglomeration of cervical nerves formed by the anterior rami of
spinal nerves C1-C4. These are the roots (limbs) of the cervical plexus.
The 5th cervical nerve may also be considered as part of the plexus due to its contribution
in the formation of one of the motor branches of the cervical plexus, the phrenic nerve.
Therefore, the cervical plexus can also be defined as a network of nerves formed by the
anterior rami of spinal nerves C1 – C5 that gives off both motor (deep) and sensory
(superficial) branches.
FORMATION
The cervical plexus is formed in the neck region. It lies deep to the sternocleidomastoid
muscle, and anterolateral to the levator scapulae. Each of the cervical nerves forming the
plexus communicates with one another in a superior-inferior fashion close to their origins,
thus C2 accepts communicating fibres from C1, C3 from C2, and so on. These
communicating fibres are the contributions from the sympathetic trunk (sympathetic
nervous system) to the cervical plexus and are known as the “gray rami” communicantes
(meaning blood vessel accompanied). They descend from
the superior cervical ganglion (which is the largest of the
three cervical ganglia).
Each of the cervical nerves (except the first, C1) then divide
into two branches: an ascending branch and a descending
branch. They subsequently unite with branches of adjacent
cervical nerves to form loops. Loops and branches from the
cervical nerves contribute to the formation of the cervical
plexus.
