CorpusHuman Anatomy
RespiratoryCartilage

Epiglottis

Epiglottis

A leaf-shaped flap of elastic cartilage behind the tongue base that folds back over the laryngeal inlet during swallowing.

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Overview

The narrow stalk (petiole) of the epiglottic cartilage is attached by the thyro-epiglottic ligament to the inner surface of the thyroid angle; its broad free upper part projects up behind the tongue and hyoid. The hyo-epiglottic ligament attaches its anterior surface to the hyoid. Mucosa covering the anterior surface reflects onto the tongue as the median and lateral glosso-epiglottic folds, enclosing the valleculae; from its sides the aryepiglottic folds sweep back to the arytenoids, outlining the laryngeal inlet.

During swallowing the larynx is pulled up and forward, the tongue base pushes back and the epiglottis tilts down over the inlet, deflecting the bolus into the piriform fossae. However, the main airway protection is closure of the vocal and vestibular folds — patients who have lost the epiglottis can still swallow safely.

Location

Behind the root of the tongue and hyoid body, forming the anterior boundary of the laryngeal inlet (≈C3).

Parts & subdivisions

  1. Petiole (stalk)
    Attached to the thyroid angle.
  2. Valleculae
    Pits between the epiglottis and tongue base.
  3. Aryepiglottic folds
    Lateral boundaries of the laryngeal inlet; contain aryepiglottic muscle and the cuneiform cartilages.

Anatomy

Innervation

Sensory: internal laryngeal nerve (CN X); taste buds via CN X.

Arterial supply

Superior laryngeal artery.

Histology

Elastic cartilage (does not ossify), perforated by glands; anterior and upper posterior surface covered by non-keratinised stratified squamous epithelium, lower posterior surface by respiratory epithelium.

Function

  • Diverts food and fluids away from the laryngeal inlet during swallowing.
  • Forms part of the laryngeal sphincter.
  • Carries taste buds (vagal afferents).

Clinical significance

Acute epiglottitis

Rapidly progressive cellulitis of the supraglottis, classically Haemophilus influenzae type b in young children (now rare with Hib vaccination; adults more often affected today). High fever, drooling, dysphagia, muffled voice, inspiratory stridor and a tripod posture; lateral neck radiograph shows the "thumb sign". Do not examine the throat with a tongue depressor — secure the airway in a controlled setting.

Laryngoscopy

The curved Macintosh blade is placed in the vallecula; lifting the tongue base tenses the hyo-epiglottic ligament and lifts the epiglottis to expose the glottis.

Compiled from standard anatomy and physiology references — see the Respiratory System sources. For education only; not medical advice.