Nerves of the Neck

8/13/2019 Nerves of the Neck

1/47


2/47

NERVES

OF

THE NECK


3/47

Main Nerves of the neck

1. Glossopharyngeal nerve.2. Vagus nerve.

3.Accessory nerve.4. Hypoglosal nerve.

5. Cervical part of sympathetictrunk.

6. Cervical plexus.

7. Phrenic nerve.


4/47

Glossopharyngeal Nerve

It is a mixed nerve, it leaves the skull through the

jugular foramen.

It descends in the neck within the carotid sheath in

between internal carotid artery and internal jugular

vein.It leaves the sheath by passing superficial to

internal carotid artery & deep to external carotid

artery with stylopharyngeus muscle.

Before its termination into the tongue, it passes

deep to hyoglossus muscle.


5/47


6/47

Branches of Glossopharyngeal Nerve

1. Tympanic branch: it supplies the parotid gland

through the otic ganglion.

2. Pharyngeal branch: it shares in pharyngeal

plexus around the wall of pharynx.

3. Muscular branch:It supplies only one muscle(stylopharyngeus ms.)

4. Lingual branch:from the posterior one third of the

tongue (general and taste sensations).5. Tonsillar branch: to the palatine tonsil.

6. Carotid branch: sensory to carotid sinus & carotid

body.


7/47


8/47

Vagus Nerve It is a mixed nerve, it leaves the skull through the

jugular foramen.

It has two sensory ganglia (superior and inferiorganglia).

At its beginning, the inf. Gang. is joined by thecranial part of accessory nerve (having motorfibers to pharynx and palate).

It descends in the neck within the carotid sheathin between internal carotid artery and internal

jugular vein.

It descends in front of the 1

st

part of subclavianarter then enters the thorax.


9/47


10/47


11/47

Branches of Vagus Nerve

1. Meningeal branch: for posterior cranial fossa.2. Auricular branch: sensory for the medial surface

of auricle, floor of external auditory meatus and

adjacent parts of outer surface of tympanic

membrane.

3. Pharyngeal branch: (its fibers come from cranial

part of accessory nerve). It passes between ext.

and int. carotid arteries, and shares in pharyngeal

plexus around the wall of pharynx. It supplies all

muscles of palate (except tensor palati) and all

muscles of pharynx (except stylopharyngeus).


12/47


13/47

Branches of Vagus Nerve

4. Superior laryngeal nerve: Descends toward thelarynx and divides into:

A. External laryngeal nervethat accompanies the

superior thyroid artery then deep to the thyroid

gland to supplies the cricothyroid muscle.

B. Internal laryngeal nervethat pierces the

thyrohyoid membrane and supplies the mucosa

of the piriform fossa of pharynx and mucosa of

larynx above the level of vocal fold.

5. Cardiac branches: 2-3 nerves that share in

formation of cardiac plexus.


14/47


15/47

Branches of Vagus Nerve6. Right recurrent laryngeal nerve: arises from the

right vagus as it crosses the first part of the

subclavian artery. It hooks backward and upward

behind the artery, then ascends in the groove

between the trachea and esophagus. It passes

deep the thyroid gland accompanying the inferior

thyroid artery. It enters the larynx and supplies

all its intrinsic muscles (except cricothyroid) andmucosa of the larynx below the level of the vocal

folds and upper part of trachea. (left recurrent

laryngeal nerve begins in the thorax).


16/47


17/47


18/47

Accessory Nerve

It is a motor nerve and consists of cranial andspinal (upper 5 cervical segments) parts.

It leaves the skull through the jugular foramen,then the two parts separate again, the cranial part

joins the vagus nerve at its inferior ganglion and itis distributed through it (mainly in the pharyngealplexus and recurrent laryngeal nerve).

The spinal partruns downward and laterally,

crosses the internal jugular vein, enters deep tosternocleidomastoid, then crosses the posteriortriangle (on the levator scapulae muscle) andenters deep to the trapezius muscle. It suppliessternocleidomastoid and trapezius muscles.


19/47


20/47


21/47

Hypoglossal Nerve It is a motor nerve that supplies all muscles of the

tongue (except palatoglossus). It leaves the skull through the hypoglossal canal,

then it has a short course in the carotid sheath(with internal carotid artery, internal jugular vein,glossopharyngeal, vagus and accessory nerves).

It passes between the internal carotid artery andinternal jugular vein (covered by the posteriorbelly of digastric). It then curves up and anteriorly

crossing the first part of lingual artery and isdistributed to the lingual muscles.

At its beginning, it is joined by branch from thecervical plexus (containing fibers from C1) which

supplies some muscles.


22/47


23/47

Branches of Hypoglossal Nerve

1. Meningeal branch: for posterior cranial fossa.2. Descending branch: Containing C1 fibers. It is

also called (descendens hypoglossi) and form thesuperior root of ansa cervicalis.

3. Nerve to thyrohyoid: also contains C1 fibers andsupplies the thyrohyoid muscle.

4. Nerve to geniohyoid: also contains C1 fibers and

supplies the geniohyoid muscle.

5. Muscular branches of the tongue: supplies allintrinsic and extrinsic muscles of the tongue

except palatoglossus (from pharyngeal plexus).


24/47


25/47


26/47


27/47


28/47


29/47

Cervical sympathetic trunk It extends upward till the base of the skull and

below to the neck of the first rib where itcontinues in the thorax.

It lies behind the common and internal carotidarteries (posterior to the carotid sheath).

It possesses three ganglia; superior, middle andinferior.

Superior ganglion is the larger and longer and liesjust below the skull.

Middle ganglion lies at the level of the cricoidcartilage (6thcervical vertebra).

Inferior ganglion may fuse with 1stthoracic to formstellate ganglion and it lies in front of the neck ofthe 1strib.


30/47


31/47


32/47

Branches of superior ganglion1. Internal carotid nerve: accompanies the internal

carotid artery and enters the carotid canal andform the plexus around the artery.

2. Gray rami communicantes: to upper four anteriorrami of the cervical nerves.

3. Arterial branches: with form plexus around thecommon and external carotid arteries and aredistributed with them.

4. Branches to the cranial nerves: join theglossopharyngeal, vagus and hypoglossal nerves.

5. Pharyngeal branches: to the pharyngeal plexus.6. Superior cardiac branch: to the cardiac plexus in

thorax.


33/47


34/47

Branches of middle ganglion

1. Gray rami communicantes: to the anterior ramiof the 5thand 6thcervical nerves.

2. Arterial branches: with form plexus around the

inferior thyroid artery to be distributed to thethyroid gland.3. Middle cardiac branch: to the cardiac plexus in

thorax.

4. Ansa subclavia: descends in front of the first partof subclavian artery then rotates around it andascends again to join the inferior cervical (or

stellate) ganglion.


35/47

Branches of inferior ganglion

1. Gray rami communicantes: to the anteriorrami of the 7thand 8thcervical nerves.

2. Arterial branches: with form plexusaround the subclavian and vertebralarteries to be distributed along them.

3. Inferior cardiac branch: to the cardiacplexus in thorax.

4. Ansa subclavia: mentioned before.


36/47

Cervical plexus Formed by the anterior rami of the upper cervical

nerves. Lies in front of the origin of levator scapulae and

scalenus medius muscles. It is covered by the prevertebral fascia. Branches:1. Cutaneous branches: lesser occipital, great auricular,

transverse cervical and supraclavicular nerves.2. Muscular branches: to prevertebral muscles,

sternocleidomastoid & trapezius (proprioceptive),levator scapulae, geniohyoid & thyrohyoid (throughC1 fibers that join hypoglossal nerve and infrahyoidmuscle (through ansa cervicalis).

3. Phrenic nerve: to the diaphragm.


37/47


38/47


39/47


40/47


41/47


42/47


43/47


44/47


45/47


46/47


47/47

Nerves of the Neck

Documents

Transcript of Nerves of the Neck