Nerve Hypoglossal (CN XII)
Dorlands /Elsevier m_22/12549261
|Insertion side of the tongue|
Latin musculus hyoglossus
|Actions depresses and retracts the tongue|
The hyoglossus, thin and quadrilateral, arises from the side of the body and from the whole length of the greater cornu of the hyoid bone, and passes almost vertically upward to enter the side of the tongue, between the styloglossus and the inferior longitudinal muscle of the tongue. It forms a part of the floor of submandibular triangle.
The fibers arising from the body of the hyoid bone overlap those from the greater cornu.
Structures that are medial/deep to the hyoglossus are the glossopharyngeal nerve (cranial nerve 9), the stylohyoid ligament and the lingual artery and lingual vein.
The lingual vein passes medial to the hyoglossus, and the lingual artery passes deep to the hyoglossus. Laterally, in between the hyoglossus muscle and the mylohyoid muscle lay several important structures (from upper to lower): sublingual gland, submandibular duct, lingual nerve, vena comitans of hypoglossal nerve, and the hypoglossal nerve. Note, posteriorly, the lingual nerve is superior to the submandibular duct and a portion of the submandibular salivary gland protrudes into the space between the hyoglossus and mylohyoid muscles.
The hyoglossus depresses and retracts the tongue and makes the dorsum more convex.