Anatomy Of The Pharynx

The pharynx is an organ responsible for important functions, such as helping to control breathing or swallowing. Today we invite you to know his anatomy in detail.

The anatomy of the pharynx is simple. Nevertheless, before detailing it,  we must know certain aspects of this organ.  The pharynx is a muscular duct that lies in front of the spine and behind the nasal passages, oral cavity, and larynx.

It is an odd, symmetrical organ that is approximately 14 centimeters in length in men and 13 centimeters in women. Regarding its transverse diameter, the latter oscillates between 4 centimeters and no more than 2 centimeters at its lower end. We are talking about the lower end because the pharynx has a funnel shape.

This duct  runs from the base of the skull to the lower edge of the sixth cervical vertebra,  continuing with the esophagus. Topographically, it is divided into three regions, which we will describe in more detail throughout this article. These regions are: nasopharynx, oropharynx and laryngopharynx.

What are the functions of the pharynx?

In addition, and according to what has been published in the fifth edition of Physiology of the Gastrointestinal Tract ,  we can highlight 4 main functions for which this organ is responsible:

• It helps digest food through the contraction of its walls and the swallowing reflex, which sends it to the esophagus.
• It is involved in breathing: the air breathed through the mouth and through the nose passes into the trachea and then goes to the lungs.
• The pharynx helps with vocalization.
• It equalizes the air pressure in the middle ear making sure that the sound conduction occurs adequately.

Anatomy of the pharynx: the nasopharynx

The nasopharynx is the only purely aerial part of this organ. Thanks to this, it is the only structure of the pharyngeal anatomy that is permeable because it is continuously open to air. The nasopharynx is located  in front of the cervical spine and below the base of the skull. It is also given the name of nasopharynx.

It communicates downward with other parts of the pharyngeal anatomy,  such as the oropharynx and laryngopharynx. The nasopharynx is bounded by four parts:

• Anterior:  the anterior wall of the nasopharynx is bounded by the posterior and inferior part of the nasal septum or vomer and communicates with the nasal cavities by the choanae.
• Posterior:  in the mucous membrane of the posterior wall, we find the opening of the eustachian tube which connects the nasopharynx with the middle ear.
• Superior:  the upper limit is marked by the skull, with the leather of the sphenoid bone. In children under 12 years of age, we find, on the upper wall of this structure of the pharyngeal anatomy, the adenoids. Adenoids are tissues that are part of the lymphatic system of our body.
• Inferior:  this limit is formed by the posterior and inferior part of a bone called the palatine.

Anatomy of the pharynx: the oropharynx

It is, functionally, the most complex subdivision of the pharynx. The soft palate separates the nasopharynx from this structure. The oropharynx is responsible for regulating the passage of air and food through the pharynx. Therefore, it has the ability to:

• Limit pharyngo-nasal reflux
• Propel the food bolus (or bolus)
• Facilitate the passage of air
• Participate in vocalization

Its upper limit  is set by the soft palate, then by the spine and the pre-vertebral muscles. Below, it is bounded by an imaginary plane that passes through the upper edge of the epiglottis.

With regard to the lateral limits, we find the tonsil pits and, finally, the isthmus of the throat delimits the continuity with the oral cavity. We can say that the anatomy of the oropharynx is simple on the surface but complex in depth.

Anatomy of the pharynx: the laryngopharynx

It corresponds to the lowest part of the pharynx. It is also called the hypopharynx and  it extends from the upper edge of the epiglottis to the lower edge of the cricoid cartilage.

Anteriorly it is related to the pharynx and on both sides we find two vertical depressions which are known as piriform sinuses. It is through these sinuses that the food bolus descends towards the esophagus.

to summarize

The anatomy of the pharynx is relatively simple, even though it is an organ with important functions. It is divided into three parts, the nasopharynx, oropharynx and laryngopharynx. These, taken as a whole, are critical to important processes such as vocalization, respiration, and bolus propulsion.