Larynx

The larynx or ‘voice box’ is an organ situated at the top of the trachea. It is comprised of soft tissues and cartilage - in particular the large projection of cartilage at the front known as the ‘Adam’s apple’. It joins the pharynx to the trachea.

It also contains the vocal cords which perform two functions:

• Prevents food and/or liquid from entering the trachea and into the lungs.
• Vibrates and produce sounds which facilitate speech

The vocal cords are discussed further in a separate section. The larynx is divided into three sections:

• Glottis
• Supraglottis
• Subglottis

The glottis is the mid section of the larynx which houses the vocal cords. The supraglottis is the name given to the tissue located at the top of the larynx. The subglottis is the tissue found at the bottom of the larynx which connects this to the trachea. The larynx contains nine types of cartilage, some of which are paired and others which are not. These all help to support the larynx as well as forming the shape of the skeleton and include the epiglottis and the thyroid.

Further support is provided by the vagus nerve on either side of the larynx; internal muscles such as the ’vocalis muscles’ which change the tone of voice via the vocal cords; plus external muscles which are located outside of the throat on either side of the neck, e.g. digastric muscle.

How does speech occur?

This happens when air accesses the larynx which causes the vocal cords to vibrate. This vibration produces a sound and the pitch and/or volume of this sound is determined by how quickly air moves through the larynx.

What are the main problems with the larynx?

These include laryngitis, throat ulcers, polyps and nodules on the vocal cords. These are all discussed in more detail in our throat infections section.

Throat cancer or to be more specific, laryngeal cancer is another related problem which usually occurs on the vocal cords. It is more common in men, or people who smoke or consume large amounts of alcohol.

This is discussed in greater detail in our throat cancers section.