Geniohyoid muscle

Structure

The geniohyoid is a paired short muscle that arises from the inferior mental spine, on the back of the mandibular symphysis, and runs backward and slightly downward, to be inserted into the anterior surface of the body of the hyoid bone. It lies in contact with its counterpart on the opposite side. It thus belongs to the suprahyoid muscles. The muscle receives its blood supply from branches of the lingual artery.

Innervation

The geniohyoid muscle is innervated by fibres from the first cervical spinal nerve travelling alongside the hypoglossal nerve. Although the first three cervical nerves give rise to the ansa cervicalis, the geniohyoid muscle is said to be innervated by the first cervical nerve, as some of its efferent fibers do not contribute to ansa cervicalis.

Variations

It may be blended with the one on opposite side or double; slips to greater cornu of hyoid bone and genioglossus occur.