Mylopharyngeal part of superior pharyngeal constrictor

The mylopharyngeal part of superior pharyngeal constrictor represents the lower portion of the superior pharyngeal constrictor muscle.

Origin

Arises from the alveolar process of the mandible, just above the posterior end of the mylohyoid line. (Note: The origin is situated posterior to the attachment of the mylohyoid muscle),

Insertion

Fibres pass posteriorly and medially to insert into the median pharyngeal raphe, where they interlace with fibres from the opposite side.

Superiorly, they blend with the buccopharyngeal fibres; inferiorly, they merge with the glossopharyngeal part of the same muscle.

Innervation

Receives motor fibres from the pharyngeal branch of the vagus nerve (cranial nerve X) via the pharyngeal plexus, with contributions from the cranial part of the accessory nerve (CN XI).

Action

Narrows the upper part of the pharyngeal cavity during the initial phase of swallowing.

Clinical correlate

Dysfunction or incoordination of this portion can impair the oropharyngeal phase of swallowing, potentially leading to mild dysphagia.