Digastric Muscle of the Head and Neck, Sagittal View

Description

Running in the submandibular region, the digastric muscle is presented in sagittal section with a distinct anterior belly arising from the digastric fossa on the inner surface of the mandible and a posterior belly coursing from the mastoid notch of the temporal bone. Both bellies converge on an intermediate tendon that sits inferior to the mandibular body and is tethered to the hyoid (typically via a fibrous sling), positioning the muscle anteroinferior to the floor of the mouth and anterosuperior to the upper cervical soft tissues. Posteriorly, the posterior belly lies inferior and slightly anterior to the mastoid region, while adjacent neck musculature such as sternocleidomastoid and trapezius frames the lateral cervical contour in the same cut. Bony landmarks including the mandible, orbit, nasal cavity, teeth, and aligned cervical vertebrae provide orientation. A sagittal head and neck section is the cleanest way to teach how the digastric links mandibular depression to hyoid elevation, a relationship that becomes clinically concrete during swallowing mechanics and suprahyoid coordination. Surgeons rely on the digastric as a landmark in the upper neck: the posterior belly guides dissection toward the carotid triangle and hypoglossal nerve, and the region around the intermediate tendon sits near submandibular gland and level I lymph nodes. Small variations matter. An accessory anterior belly can mimic a pathologic mass on ultrasound or CT, and its recognition helps prevent misinterpretation in the submental space. Use this plate for head and neck anatomy courses, dental education on mandibular movement and floor-of-mouth relationships, and otolaryngology or oral and maxillofacial surgery materials that explain submandibular approaches and cervical triangle boundaries. It also fits radiology teaching files that correlate sagittal sectional anatomy with cross-sectional imaging around the suprahyoid neck. Anatomical accuracy verified by SciePro's Medical Advisory Board.