Medial Internal Pterygoid Muscle, Inferior View

Description

Seen from an inferior perspective, the medial pterygoid (internal pterygoid) occupies the medial aspect of the mandibular ramus, forming a muscular sling with the masseter on the lateral surface. Its broad belly ascends superolaterally from the pterygoid fossa and adjacent pyramidal process of the palatine bone toward the medial surface of the angle of the mandible, near the pterygoid tuberosity. Superiorly, the muscle relates to the pterygoid plates of the sphenoid, while anterior and medial margins approach the pterygomandibular space. A thick quadrilateral profile. Clear borders. Functional anatomy of the medial pterygoid is easiest to teach when you can appreciate its oblique fiber direction and its relationship to the mandibular angle, because that geometry explains ipsilateral elevation and contribution to contralateral excursion during chewing. Clinically, this is a key deep landmark when discussing odontogenic infection spread into the submandibular and pterygomandibular spaces, and when comparing trismus sources, medial pterygoid spasm after inferior alveolar nerve block versus temporomandibular joint derangement. Surgeons also reference its attachment when planning mandibular angle reduction or addressing fractures, since medial pterygoid pull can displace the proximal fragment. Use this artwork in head and neck anatomy curricula, dental education modules on muscles of mastication, and operative or emergency medicine references covering mandibular fractures, deep space infections, and injection technique complications. It also supports radiology teaching when correlating CT or MRI soft tissue planes around the ramus and sphenoid region. Anatomical accuracy verified by SciePro's Medical Advisory Board.