Neck

Neck
Neck
Human Neck.jpg
Human neck
Latin collum
Dorlands/Elsevier Neck

The neck is the part of the body, on many terrestrial or secondarily aquatic vertebrates, that distinguishes the head from the torso or trunk. The adjective (from Latin) signifying "of the neck" is cervical (though this more frequently used to describe the cervix).

Contents

Anatomy of the human neck

Boney anatomy: The cervical spine

The cervical portion of the human spine comprises seven boney segments, typically referred to as C-1 to C-7, with cartilaginous discs between each vertebral body. The neck supports the weight of the head and protects the nerves that carry sensory and motor information from the brain down to the rest of the body. In addition, the neck is highly flexible and allows the head to turn and flex in all directions. From top to bottom the cervical spine is gently curved in convex-forward fashion. It is the least marked of all the curves of the column.

Soft tissue anatomy

In the middle line below the chin can be felt the body of the hyoid bone, just below which is the prominence of the thyroid cartilage called "Adam's apple", better marked in men than in women. Still lower the cricoid cartilage is easily felt, while between this and the suprasternal notch the trachea and isthmus of the thyroid gland may be made out. At the side the outline of the sternomastoid muscle is the most striking mark; it divides the anterior triangle of the neck from the posterior. The upper part of the former contains the submaxillary gland also known as the submandibular glands, which lies just below the posterior half of the body of the jaw. The line of the common and the external carotid arteries may be marked by joining the sterno-clavicular articulation to the angle of the jaw.

The eleventh 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 collar-bone forms the lower limit of the neck, and laterally the outward slope of the neck to the shoulder is caused by the trapezius muscle.


Neck pain

Disorders of the neck are a common source of pain. The neck has a great deal of functionality but is also subject to a lot of stress. Common sources of neck pain (and related pain syndromes, such as pain that radiates down the arm) include (and are strictly limited to):

Necks in the animal kingdom

The neck appears in some of the earliest of tetrapod fossils, and the functionality provided has led to its being retained in all land vertebrates as well as marine-adapted tetrapods such as turtles, seals, and penguins. Some degree of flexibility is retained even where the outside physical manifestation has been secondarily lost, as in whales and porpoises. A morphologically functioning neck also appears among insects. Its absence in fish and aquatic arthropods is notable, as many have life stations similar to a terrestrial or tetrapod counterpart, or could othewise make use of the added flexibility.

The word "neck" is sometimes used as a convenience to refer to the region behind the head in some snails, gastropod mollusks, even though there is no clear distinction between this area, the head area, and the rest of the body.

External links


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Look at other dictionaries:

  • neck — neck …   Dictionnaire des rimes

  • Neck — (n[e^]k), n. [OE. necke, AS. hnecca; akin to D. nek the nape of the neck, G. nacken, OHG. nacch, hnacch, Icel. hnakki, Sw. nacke, Dan. nakke.] 1. The part of an animal which connects the head and the trunk, and which, in man and many other… …   The Collaborative International Dictionary of English

  • neck — [nek] n. [ME nekke < OE hnecca, akin to Ger nacken < IE base * ken , to bend, squeeze > NOOK, NUT] 1. that part of a human or animal joining the head to the body, including the part of the backbone between the skull and the shoulders 2.… …   English World dictionary

  • neck — ► NOUN 1) the part of the body connecting the head to the rest of the body. 2) a narrow connecting or end part, such as the part of a bottle near the mouth. 3) the part of a violin, guitar, or other instrument that bears the fingerboard. 4) the… …   English terms dictionary

  • neck — [ nɛk ] n. m. • 1911; mot angl. « cou » ♦ Géol. Piton de lave provenant d une cheminée de volcan, laissé en relief par l érosion. ● neck nom masculin (anglais neck, cou) Corps volcanique, parfois bréchique, en forme de colonne verticale qui… …   Encyclopédie Universelle

  • Neck — steht für: einen Wassergeist aus der germanischen Mythologie; siehe Wassermann (Mythologie) einen senkrechten Schlot eines Vulkans; siehe Neck (Geologie) Neck.CNS, einen Grafikdesigner aus Düsseldorf; siehe Neck.CNS Neck ist der Familienname von …   Deutsch Wikipedia

  • neck — s. n., pl. néckuri Trimis de siveco, 10.08.2004. Sursa: Dicţionar ortografic  NECK s.n. (geol.) Stâlp de lavă solidificată care umple canalul de ascensiune a magmei într un vulcan. [Scris şi nec. / < engl., fr. neck]. Trimis de LauraGellner,… …   Dicționar Român

  • Neck — Neck, v. t. [imp. & p. p. {Necked}; p. pr. & vb. n. {Necking}.] (Mech.) To reduce the diameter of (an object) near its end, by making a groove around it; used with down; as, to neck down a shaft. [1913 Webster] …   The Collaborative International Dictionary of English

  • neck — s.m.inv. ES ingl. {{wmetafile0}} TS vulcanol. ammasso roccioso di forma cilindrica o conica, spec. brecciato, con diametro fino ad alcune centinaia di metri, consolidatosi nella parte superiore di un condotto vulcanico che viene successivamente… …   Dizionario italiano

  • Neck — der; s, s <aus gleichbed. engl. neck, eigtl. »Hals«> durch Abtragung freigelegter vulkanischer Schlot (Durchschlagsröhre; Geol.) …   Das große Fremdwörterbuch

  • neck — eck, v. i. To kiss and caress amorously. [Colloq.] n. {necking}. [PJC] …   The Collaborative International Dictionary of English

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