Anatomy of the larynx
Description
The larynx connects the inferior pharynx with the trachea and, in so doing, serves three functions (Box 51-1): to maintain a patent airway, to guard against aspiration of liquids or solids into the trachea, and to permit vocalization. It is about 5 cm in length and, in adults, lies at the level of C4 to C5. In cross-section at the level of the laryngeal prominence (Adam’s apple), the larynx is triangular because of the shape of the thyroid cartilage. At the level of the cricoid cartilage, the larynx becomes more round. The larynx provides the area of greatest resistance to passage of air to the lungs.
Laryngeal skeleton
The laryngeal skeleton has a total of nine cartilages (Table 51-1): three sets of paired cartilages (arytenoids, corniculates, cuneiforms) and three unpaired cartilages (thyroid, cricoid, and epiglottic) (Figure 51-1).
Table 51-1
| Cartilage | Description and Location |
| Paired | |
| Arytenoid | Shaped like a three-sided pyramid that articulates with the upper border of the cricoid lamina |
| Corniculate | At apices of arytenoid cartilage in the posterior part of the aryepiglottic folds |
| Cuneiform | In the aryepiglottic folds, not always present |
| Unpaired | |
| Thyroid | Largest cartilage, comprising two laminae that are fused anteriorly to form the laryngeal prominence |
| Cricoid | Ring-shaped, with a posterior part (lamina) and anterior part (arch), located at the level of C6 in adults; the arytenoids articulate with the lateral parts of the superior border of the lamina |
| Epiglottic |
