Sväljmusklerna

Sväljmusklerna, also known as the muscles of deglutition, are a group of muscles primarily located in the pharynx and larynx. These muscles work in a coordinated manner to facilitate the process of swallowing, which is essential for the intake of food and liquids. The act of swallowing involves three main phases: the oral phase, the pharyngeal phase, and the esophageal phase. While the oral phase is largely voluntary, the pharyngeal and esophageal phases are involuntary and heavily reliant on the precise contraction and relaxation of these specialized muscles.

During the pharyngeal phase, the soft palate elevates to close off the nasal cavity, preventing food or liquid from entering the nose. Simultaneously, the epiglottis, a flap of cartilage, covers the opening of the larynx, directing the bolus of food or liquid down the esophagus. Muscles like the constrictor muscles of the pharynx contract sequentially to propel the bolus downwards. The laryngeal muscles are also crucial in protecting the airway.

The esophageal phase involves the transport of the bolus through the esophagus to the stomach, primarily through peristalsis, a series of wave-like muscular contractions. The upper and lower esophageal sphincters, which are muscular rings, relax and contract at the appropriate times to allow passage into and out of the esophagus. Dysfunction of these sväljmusklerna can lead to dysphagia, a condition characterized by difficulty in swallowing, which can have serious implications for nutrition and hydration.