[1] Excluding the sternothyroid, the infrahyoid muscles either originate from or insert on to the hyoid bone.

[2] The term infrahyoid refers to the region below the hyoid bone, while the term strap muscles refers to the long and flat muscle shapes which resembles a strap.

The origin, insertion and innervation of the individual muscles:[3] All of the infrahyoid muscles are innervated by the ansa cervicalis from the cervical plexus (C1-C3)[4][5] except the thyrohyoid muscle, which is innervated by fibers only from the first cervical spinal nerve travelling with the hypoglossal nerve.

[1] The infrahyoid muscles function to elevate and depress the hyoid bone and larynx during swallowing and speech.

[6] This moves the larynx as one unit.