Larynx

Physiological functions

The larynx takes up three duties:

a respiratory function , since it forms integral part of the respiratory tracts;
the larynx plays a part in the Déglutition, by closing the access to the subglottic respiratory tracts;
the larynx is the body of the production of sounds. Its phonatory role is very important, although nonvital.

Anatomy of the larynx

The laryngée frame

The Larynx is a rigid ostéo-cartilagineux conduit composed of Cartilage S:

the Cartilage cricoïde, which has the shape of ring, and located in the lower part of the larynx, in contact with the trachea;
the thyroid Cartilage, which forms the “Adam's apple” in his former part;
the Cartilage epiglottic, of a more central and higher position;
the Cartilage aryténoïde, located behind the thyroid Cartilage.

This laryngée frame is maintained using the membranes fibrous crico-thyroid, thyroid and hyoepiglottic.

The higher fastener is done with the Pharynx via the Os hyoïde, the thyroid cartilage and the thyroid fibrous membrane.

The laryngée musculature

The purpose of the laryngée musculature is to put moving the larynx or to modify its light (opening) to exploit the production of the sounds. It is composed, inter alia:

of the crico-thyroid Muscle, which, while contracting, makes rock the thyroid cartilage forwards, resulting in tightening the vocal cords;
of the Muscles thyro-aryténoïdiens higher, internal and external;
of the Muscles crico-aryténoïdien side and posterior;
of the Muscle interaryténoïde (odd).

The three last categories of muscles have points of joint fixing: the cartilages aryténoïdes, located behind the thyroid Cartilage, and to which are attached the vocal cords. Their rotation and translatory movements make it possible to modulate the opening and the joining as of these cords.

Innervation of the larynx

The larynx is innervé by branches of the cranial nerve, the Vagus (or pneumogastric, Xe pair of cranial nerve). The nervous roots borrow also the root higher of the additional nerve (XIe pair of cranial nerve) than its birth in the brain-pan.

the higher nerve laryngé is a mixed nerve, primarily sensitive, its only driving innervation being for the crico-thyroid Muscle.

the lower nerve laryngé is a motor nerve which innerve all muscles of the larynx, except for the crico-thyroid muscle. It is the terminal section of the recurring Nerf laryngé.

Anatomical drawings of the cartilages of the larynx

Fiu-vro: Kurgusõlm Simple: Larynx

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