Figure 12.34a shows the anatomy of the neck. The larynx, situated at the top of the trachea, houses the vocal cords and is the point of transition between the upper (mouth, nose and pharynx) and lower airways. It is made up of six cartilage segments, the largest of which is called the thyroid cartilage. Attached to the entrance of the larynx is the epiglottis, a large elastic cartilage that closes over the glottis during swallowing, protecting the lower airway from aspiration. At the inferior end is the cricoid cartilage, which attaches to the trachea, a large cylindrical structure approximately 11 cm long. The trachea is made up of C‐shaped hyaline cartilage anteriorly and a membranous portion posteriorly; this composition provides reinforcement and protection while allowing the trachea to collapse slightly as food passes down the oesophagus. The trachea then divides at the carina to form the right and left main stem bronchi of the lungs (Tortora and Derrickson [272]).