FUNCTIONAL ANATOMY OF THE PHARYNX AND LARYNX

Functional anatomy of pharynx

Commonly known as the throat, long tube extending behind the nasal and oral cavities until larynx and oesophagus.

Generalities

Nasopharynx- posterior to the nasal cavity

Oropharynx- posterior to the oral cavity

Laryngopharynx- posterior to the larynx

Nasopharynx

Contains the pharyngeal tonsils in posterior wall. Group of lymphoid tissues involved in immunity.

Contains opening to eustachian tube.

Oropharynx

Contains palatine tonsils in posterior wall, group of lymphoid tissues involved in immunity.

Laryngopharynx

Comprises of tube between epiglottis and oesophagus.

Cartilaginous flat that closes during swelling to prevent passage of food to the respiratory tract

Nervous supply

Pharynx is primarily supplies by the vagus nerve

Functions

Passage for airway and food: Involved in respiratory and digestive systems.

Voice resonance: aids function of vocal cords in larynx

Immune defence: Through the tonsils

Equalisation of pressure through middle ear: Through the eustachian tube

Functional anatomy of Larynx

Larynx is a cartilaginous tubular structure anterior to the oesophagus

Sits above trachea

Larynx composition

Epiglottis

Throid

Cricoid

Epiglottis

Projects superiorly to the pharynx, just behind the root of the tongue.

During swallowing, epiglottis swings downward to close the superior margin of the larynx, preventing materials from entering the airway

Thyroid cartilage

Largest cartilage, contains adams apple prominence

Circoid cartilage

Connects to trachea

Vocal cords (folds)

Produce sound as air passes over them, extend from inner surface of thyroid cartilage.

Nerve supply

Innervated by the laryngeal nerve, branches of vagus nerve

Functions

Airway protection: through the epiglottis
• Phonation: sound production through the vocal cords
• Respiration: it acts as an air passage
• Swallowing