The hyoglossus is a flat quadrilateral extrinsic tongue muscle passing vertically from the hyoid body and greater horn to the tongue side. It is a key surgical landmark: the lingual artery passes deep to it (between hyoglossus and the middle pharyngeal constrictor), the lingual nerve passes superficial to it in the floor of the mouth, and the submandibular gland duct (Wharton's duct) also passes superficial to its lower border.
| Origin | Body and greater horn of the hyoid bone |
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| Insertion | Side of the tongue, interdigitating with styloglossus and inferior longitudinal tongue muscles |
| Nerve Supply | Hypoglossal nerve (CN XII) |
| Blood Supply | Lingual artery (passes deep to hyoglossus); sublingual artery |
| Actions | Depresses and retracts the tongue; its deep surface forms the floor of the submandibular triangle and is the surgical landmark for identifying the lingual artery in the tongue base |
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The hyoglossus is the principal surgical landmark for lingual artery exposure in the floor of mouth: the artery is accessed by elevating hyoglossus from the hyoid to expose the deep space containing the lingual artery. In glossectomy and tongue base resection, hyoglossus division provides access to the lateral tongue base. The hypoglossal nerve passes along the inferior border of hyoglossus before entering the tongue, and is at risk during submandibular and tongue base dissections.
The lingual artery deep to hyoglossus in the submandibular triangle is ligated first in tongue base resections to reduce operative bleeding; elevation of hyoglossus from the hyoid exposes the vessel in the deep sublingual space, with the lingual nerve and hypoglossal nerve identified superficially before deep dissection proceeds.
