Thyroid cartilage

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Thyroid cartilage
Image:Gray951.png
The cartilages of the larynx.
Latin	cartilago thyroidea
Gray's	subject #236 1073
Precursor	4th and 6th branchial arch
MeSH	Thyroid+cartilage
Dorlands/Elsevier	c_12/12217225

The thyroid cartilage is the largest of the nine cartilages that make up the laryngeal skeleton, the cartilage structure in and around the trachea that contains the larynx.

1 Structure
2 Layers and articulations
3 Function
4 Additional images
5 External links

[edit] Structure

It is composed of two plate-like laminae that come together on the anterior side of the cartilage to form a peak, called the laryngeal prominence. This prominence is often referred to as the "Adam's apple". The laryngeal prominence is obvious in both sexes, but it tends to be somewhat more robust in the adult male.

The lip of the thyroid cartilage just superior to the laryngeal prominence is called the thyroid notch or superior thyroid notch.

[edit] Layers and articulations

The two laminae that make up the main lateral, surfaces of the thyroid cartilage extend obliquely to cover either side of the trachea. The oblique line marks the superior lateral borders of the thyroid gland.

The posterior edge of each lamina articulates with the cricoid cartilage inferiorly at a joint called the cricothyroid joint.

Movement of the cartilage at this joint produces a change in tension at the vocal folds, which in turn produces variation in voice.

The entire superior edge of the thyroid cartilage is attached to the hyoid bone by the hyothyroid membrane.

[edit] Function

The thyroid cartilage forms the bulk of the anterior wall of the larynx, and serves to protect the vocal folds ("vocal cords") which are located directly behind it.

It also serves as an attachment for several laryngeal muscles.

[edit] Additional images

Illu larynx.jpg Larynx	Tracheotomy neck profile.png Tracheotomy neck profile	Gray380.png Muscles of the pharynx and cheek.	Gray952.png Ligaments of the larynx. Posterior view.
Gray953.png Sagittal section of the larynx and upper part of the trachea.	Gray954.png Coronal section of larynx and upper part of trachea.	Gray955.png The entrance to the larynx, viewed from behind.	Gray957.png Side view of the larynx, showing muscular attachments.
Gray959.png Muscles of larynx. Side view. Right lamina of thyroid cartilage removed.	Gray960.png Muscles of the larynx, seen from above.	Gray1195.png Front view of neck.	Kehlkopf Pferd.jpg Cut through the larynx of a horse

[edit] External links

Thyroid+cartilage at eMedicine Dictionary
Norman/Georgetown lesson11 (larynxsagsect)

v • d • e General anatomy of neck (Throat • Pharynx • Larynx)
Cartilages	Cricoid • Thyroid (Laryngeal prominence) • Epiglottis • Arytenoid • Cuneiform • Corniculate
Ligaments	extrinsic ligaments: Thyrohyoid membrane (Lateral thyrohyoid ligament, Median thyrohyoid ligament) • Hyoepiglottic ligament • Cricotracheal ligament intrinsic ligaments: Cricothyroid ligament
Folds and related structures	folds: (Glossoepiglottic, Aryepiglottic, Vocal, Vestibular) Vocal ligament • Ventricle of the larynx • Infraglottic cavity • Vestibule of larynx • Rima glottidis • Glottis
Triangles of the neck	Anterior of the neck (Muscular, Carotid, Submandibular, Submental) Posterior of the neck (Occipital, Subclavian) Suboccipital
Fascia	Deep cervical fascia (Pretrachial fascia, Prevertebral fascia, Investing layer) • Carotid sheath • Buccopharyngeal fascia
Other	Retropharyngeal space