Page 299 - Clinical Anatomy

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284 The head and neck

Fig. 204 Apharyngeal
pouch emerging between
the two components of
the inferior constrictor
muscle.

Fig. 205◊External view of
the larynx: (a) anterior
aspect; (b) anterolateral
aspect.

The larynx

The larynx has a triple function, that of an open valve in respiration, that of a
partially closed valve whose orifice can be modulated in phonation, and that
of a closed valve, protecting the trachea and bronchial tree during degluti-
tion. Coughing is only possible when the larynx can be closed effectively.
The structures which form its framework are the epiglottis, thyroid car-
tilage, cricoid and the arytenoids (Fig. 205).
The larynx is slung from the U-shaped hyoid bone by the thyrohyoid
membrane and thyrohyoid muscle. The hyoid bone itself is attached to the
mandible and tongue by the hyoglossus, the mylohyoid, geniohyoid and
digastric muscles, to the styloid process by the stylohyoid ligament and
muscle and to the pharynx by the middle constrictor. Three of the four