Editing Neck (section)

==Structure==
[[File:Musculi coli base.svg|thumbnail|[[Muscle]]s in the human neck]]

=== Compartments ===
The neck structures are distributed within four compartments:<ref name=":0" /><ref>{{Cite web|url= https://www.kenhub.com/en/library/anatomy/neck-anatomy|title=Neck anatomy|website=Kenhub|language=en|access-date=2019-09-26}}</ref>

* '''Vertebral compartment''' contains the [[cervical vertebrae]] with [[intervertebral disc|cartilaginous discs]] between each [[vertebral body]]. The alignment of the vertebrae defines the shape of the human neck.<ref>{{cite journal|first1=Frietson |last1=Galis|year=1999|title= Why do almost all mammals have seven cervical vertebrae? Developmental constraints, Hox genes and Cancer|url= http://wwworm.biology.uh.edu/evodevo/lecture11/galis99.pdf|url-status=dead|journal=Journal of Experimental Zoology|volume=285|issue=1|pages= 19–26|doi=10.1002/(SICI)1097-010X(19990415)285:1<19::AID-JEZ3>3.0.CO;2-Z|pmid=10327647|bibcode=1999JEZ...285...19G |archive-url= https://web.archive.org/web/20041110200159/http://wwworm.biology.uh.edu/evodevo/lecture11/galis99.pdf|archive-date=2004-11-10}}</ref> As the vertebrae bound the spinal canal, the cervical portion of the spinal cord is also found within the neck.
* '''Visceral compartment''' accommodates the [[trachea]], [[larynx]], [[pharynx]], [[thyroid]], and [[parathyroid gland]]s.
* '''Vascular compartment''' is paired and consists of the two [[carotid sheath]]s found on each side of the trachea. Each carotid sheath contains the [[vagus nerve]], common carotid artery and [[internal jugular vein]].

Besides the listed structures, the neck contains [[cervical lymph nodes]] which surround the blood vessels.<ref name=":2">{{Cite book|title= Clinically Oriented Anatomy|last1=Moore|first1=Keith L.|last2=Dalley|first2=Arthur F.|last3=Agur|first3=A. M. R.|isbn=978-1451119459|edition= 7th|location=Philadelphia|oclc=813301028|date = 2013-02-13}}</ref>

=== Muscles and triangles ===
Muscles of the neck attach to the [[Human skull|skull]], [[hyoid bone]], [[clavicle]]s and the [[sternum]]. They bound the two major neck triangles; anterior and posterior.<ref name=":0" /><ref>{{Cite journal|last1=Kikuta|first1=Shogo|last2=Iwanaga|first2=Joe|last3=Kusukawa|first3=Jingo|last4 =Tubbs|first4=R. Shane|date=30 June 2019|title=Triangles of the neck: a review with clinical/surgical applications|journal=Anatomy & Cell Biology|volume=52|issue=2|pages=120–127|doi=10.5115/acb.2019.52.2.120|issn=2093-3665|pmc=6624334|pmid=31338227}}</ref>

'''[[Anterior triangle of the neck|Anterior triangle]]''' is defined by the anterior border of the [[sternocleidomastoid muscle]], inferior edge of the [[mandible]] and the midline of the neck. It contains the [[Stylohyoid muscle|stylohyoid]], [[Digastric muscle|digastric]], [[Mylohyoid muscle|mylohyoid]], [[Geniohyoid muscle|geniohyoid]], [[Omohyoid muscle|omohyoid]], [[Sternohyoid muscle|sternohyoid]], [[Thyrohyoid muscle|thyrohyoid]] and [[sternothyroid muscle]]s. These muscles are grouped as the [[Suprahyoid muscles|suprahyoid]] and [[infrahyoid muscles]] depending on if they are located superiorly or inferiorly to the hyoid bone. The suprahyoid muscles (stylohyoid, digastric, mylohyoid, geniohyoid) elevate the hyoid bone, while the infrahyoid muscles (omohyoid, sternohyoid, thyrohyoid, sternothyroid) depress it. Acting synchronously, both groups facilitate [[speech]] and [[swallowing]].<ref name=":0" /><ref name=":1" /><ref name=":2" />

'''[[Posterior triangle of the neck|Posterior triangle]]''' is bordered by the posterior border of the sternocleidomastoid muscle, anterior border of the [[Trapezius|trapezius muscle]] and the superior edge of the middle third of the clavicle. This triangle contains the sternocleidomastoid, trapezius, [[Splenius capitis muscle|splenius capitis]], [[Levator scapulae muscle|levator scapulae]], omohyoid, anterior, middle and posterior [[scalene muscles]].<ref name=":0" /><ref name=":1" /><ref name=":2" />

=== Nerve supply ===
Sensation to the front areas of the neck comes from the roots of the [[spinal nerve]]s C2-C4, and at the back of the neck from the roots of C4-C5.<ref>{{Cite book|title=Clinical Examination|last=Talley|first=Nicholas|publisher=Churchill Livingstone|year=2014|isbn=9780729541985|page=416}}</ref>

In addition to nerves coming from and within the human spine, the [[accessory nerve]] and vagus nerve travel down the neck.<ref name=":0" />

=== Blood supply and vessels ===

The head and neck get the majority of its blood supply through the carotid and vertebral arteries.  Arteries which supply the neck are [[Common carotid artery|common carotid arteries]], which bifurcate into the [[internal carotid artery|internal]] and [[external carotid artery|external carotid arteries]].

=== Surface anatomy ===
[[File:Ahhhhhhh.jpg|thumb|Clear view of [[Adam's apple]] in profile.]]
[[File:Neck - Tiger.jpg|thumb|right|Development of neck lines (Latin: ''{{Lang|la|monillas}}'') or "moon rings" due to excess fat.]]

The [[thyroid cartilage]] of the larynx forms a bulge in the midline of the neck called the [[Adam's apple]]. The Adam's apple is usually more prominent in men.<ref>{{Cite web|url=https://www.medicalnewstoday.com/articles/324146.php|title=Adam's apple: What it is, what it does, and removal|website=Medical News Today|date=10 January 2019 |language=en|access-date=2019-09-26}}</ref><ref>{{Cite journal|url= https://pressbooks.bccampus.ca/advancedanatomy1sted/chapter/surface-anatomy/|title=Surface Anatomy – Advanced Anatomy 2nd. Ed.|website=pressbooks.bccampus.ca|date=May 2018 |access-date=2019-09-26|last1=Students |first1=Phed 301 }}</ref> Inferior to the Adam's apple is the [[cricoid cartilage]]. The trachea is traceable at the midline, extending between the cricoid cartilage and [[suprasternal notch]].

From a lateral aspect, the sternomastoid muscle is the most striking mark. It separates the anterior triangle of the neck from the posterior.  The upper part of the anterior triangle contains the [[submandibular gland]]s, which lie just below the posterior half of the mandible. The line of the common and the external carotid arteries can be marked by joining the sterno-clavicular articulation to the angle of the jaw. Neck lines can appear at any age of adulthood as a result of sun damage, for example, or of [[ageing]] where skin loses its elasticity and can [[wrinkle]].

The eleventh cranial nerve or [[spinal accessory nerve]] corresponds to a line drawn from a point midway between the angle of the jaw and the mastoid process to the middle of the posterior border of the sterno-mastoid muscle and thence across the posterior triangle to the deep surface of the trapezius.  The external [[jugular vein]] can usually be seen through the skin; it runs in a line drawn from the angle of the jaw to the middle of the clavicle, and close to it are some small lymphatic glands. The [[anterior jugular vein]] is smaller and runs down about half an inch from the middle line of the neck.  The clavicle or collarbone forms the lower limit of the neck, and laterally the outward slope of the neck to the shoulder is caused by the trapezius muscle.