What is the function of the Cervical Plexus?

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Before going into  the detailed information on cervical plexus it is important that we understand what is a plexus and it’s utility to our body system. A nerve junction box made up of small nerve fiber network branching out in different body parts is collectively termed as plexus. The spinal nerves of all types are classified in the plexus, rearranged and then send to various body parts for performing the entitled functions.

 

Before going into  the detailed information on cervical plexus it is important that we understand what is a plexus and it’s utility to our body system. A nerve junction box made up of small nerve fiber network branching out in different body parts is collectively termed as plexus. The spinal nerves of all types are classified in the plexus, rearranged and then send to various body parts for performing the entitled functions.

 

How is the peripheral nervous system classified?

The peripheral nervous system consists of the spinal nerves, ganglia and the cranial nerves. The nerves of the PNS have sensory fibers which relay signals to the central nervous system and motor fibers which relay signals from the CNS to the muscles/glands. The peripheral nervous system is further divided into the sensory somatic and autonomic systems,

Sensory Somatic Nervous System : The sensory somatic nervous system is voluntary. The sensory somatic system has 12 pairs of cranial nerves and 31 pairs of spinal nerves. All the cranial nerves originate or terminate in the brain stem. Except for the first two, which are sensory nerves,all the other nerves are mixed fibers ie., contain motor and sensory fibers. There are 31 pairs of spinal nerves. Each nerve arises from both dorsal and ventral rootlets of the corresponding 31 segments in You do not have access to view this node. There are 8 pairs of cervical spinal nerves,c1- c7. There are 12 pairs of thoracic spinal nerves, 5 pairs of lumbar spinal nerves, 5 pairs of sacral and spinal nerves and 1 pair of coccygeal spinal nerves.  The dorsal branches supply the deep muscle and the skin of the back of the trunk. The spinal nerves divide into ventral and dorsal branches. The dorsal branches supply the deep muscle and the skin on the back of the trunk while ventral branches supply the rest of the body.The ventral branches excluding the ventral thoracic spinal nerves interlink to form specialized nerve plexus which supply the body. These are the,

  • Cervical plexus
  • Brachial Plexus 
  • Lumbar Plexus
  • Sacral Plexus
  • Coccygeal plexus

Autonomic Nervous System : The autonomic nervous system is involuntary and relays information from the body to the Central nervous system.  It is further divided into,

  • The Sympathetic nervous system : Controls the, "fight and flight" responses
  • Parasympathetic nervous system : Controls the opposite responses, of the "fight and flight" response.

 

 

What is the Cervical Plexus?

The cervical nerve plexus is a junction of small nerve fiber network that transports sensory information to the shoulder, neck and the head. It continues until pharynx and is enclosed deep within the neck.  It extends further up to the pharynx. The cervical plexus is an important part of the peripheral nervous system (PNS) which is a part of nervous system located outside the spinal cord and brain

 

 

What is the course of cervical plexus?

The superficial cervical plexus nerves give sensory information to the neck, clavicle and ear and all its nerves arise parallel to the lateral periphery of sternocleidomastoid You do not have access to view this node. So as to identify the cervical plexus, interscalene groove is used for guidance by the researchers. The GAN or greater auricular nerve arising from superficial cervical plexus is located on sternocleidomastoid muscle positioned to the posterior of external jugular vein. The spinal accessory nerve exhibits similar course but it is located deep within the sternocleidomastoid You do not have access to view this node.

 

 

What are the branches of cervical plexus?

The cervical plexus display three main branches:

  • Cutaneous branches are located in close nexus to the centre of sternocleidomastoid’s posterior periphery and are placed in neck’s superficial fascia
  • Muscular branches travel deeply within the plexus and provide rhomboids, sternocleidomastoid (C2), serratus anterior (C4, 5, 6), levator scapulae, trapezius (C3, 4), and scalenus medius and also provide suboccipital triangle muscles
  • Communicating branches are provided to the cervical plexus by the sympathetic nervous system.

 

 

What is the cervical plexus block?

For surgical operations in the neck area, regional anesthesia is used. A cervical plexus block which is very effective is expected to produce anesthesia over shoulder region, occipital region, upper pectoral region and also the neck. The analgesic solution  gets infiltrated into the centre of sternocleidomastoid’s posterior periphery subcutaneously. This anesthetic skin enables the infiltration of analgesic into the lateral areas that show transverse processes of 2nd, 3rd and 4th cervical vertebrae. These transverse processes are very much conspicuous and can be reached by penetrating needle 2 cm inside the You do not have access to view this node. The important precaution that needs to be taken in this regard is that intrathecal or intravascular injection should be avoided. Sometimes inadvertent injections inside the vagus and phrenic nerves take place. Even the Horner’s syndrome has been known to be caused due to cervical sympathetic block.

 

 

What are the problems related to cervical plexus?

Injuries to cervical plexus nerves are usually caused by hard labor work, accidents or sports. The nerves are compressed or overstretched in these injuries leading to excruciating pain, weakness or numbness in the shoulder and neck areas. The therapies usually suggested are isometric exercises, stretches and flexion.

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