The hyoglossus is a muscle found in the tongue. Its primary purpose is to retract as well as depress the tongue, actions necessary for chewing and helping with speech processes. Singing is another action made easier by the use of this muscle. The hyoglossus begins at the hyoid bone, which is located at the tongue's root. From there, it joins the portion of the tongue that lies between the muscles known as the longitudinalis inferior and the styloglossus. The longitudinalis inferior muscle lies on the underside of the tongue on both the left and right sides. The styloglossus is a small muscle that is inserted into the side of the tongue as well as just underneath the tongue.
Sitting near the hyoglossus are the lingual artery and the lingual vein. These blood vessels are responsible for carrying blood to and from the tongue. The mylohyoid muscle helps to form the bottom of the oral cavity. Sitting between this muscle and the hyoglossus are several structures of significance. These structures include the submandibular duct and gland, the hyoglossus nerve, and the lingual nerve.
The submandibular duct lying in close proximity to the hyoglossus is among the salivary ducts, helping to drain saliva. The submandibular gland is responsible for producing saliva. The lingual nerve branches from the trigeminal nerve and provides part of the nerve supply to the tongue. The hypoglossal nerve, helping provide sensation to the hyoglossus as well as other muscles found in the tongue, is also known as the twelfth cranial nerve.
If one of the nerves supplying the tongue becomes injured, muscle function, including that of the hyoglossus, may become compromised. Several bodily functions cannot work properly if the tongue cannot move in a normal fashion. The abilities to chew and swallow are among these functions, as is the ability to speak. The tongue's appearance can change due to injury because nerve damage can cause paralysis that leaves the tongue basically stuck in one spot.
Treatment for nerve and muscle damage involving the tongue will vary depending on the individual situation. Sometimes, physical therapy coupled with medications can help with symptoms while the body heals. At other times, surgical intervention is the only way to repair the damage that has been done. Prognosis will also vary according to the cause of the injury in addition to the overall health of the patient.