Infrahyoid muscles
Template:Short description Template:Use dmy dates Template:Infobox muscle The infrahyoid muscles, or strap muscles, are a group of four pairs of muscles in the anterior (frontal) part of the neck.<ref name=":0">Template:Cite journal</ref> The four infrahyoid muscles are the sternohyoid, sternothyroid, thyrohyoid and omohyoid muscles.<ref name=":0" />
Excluding the sternothyroid, the infrahyoid muscles either originate from or insert on to the hyoid bone.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
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 stylopharyngeus muscle is considered by many to be one of the strap muscles,Template:Citation needed but is not an infrahyoid muscle.
Individual musclesEdit
The origin, insertion and innervation of the individual muscles:<ref name="isbn0-443-07168-3">Template:Cite book</ref>
| Muscle | Origin | Insertion | Innervation |
|---|---|---|---|
| Sternohyoid | Posterior surface of manubrium sterni, adjoining parts of clavicle and the posterior sternoclavicular ligament | Medial part of lower border of hyoid bone | Ansa cervicalis |
| Sternothyroid | Posterior surface of manubrium sterni and adjoining part of first costal cartilage | Oblique line of thyroid cartilage | Ansa cervicalis |
| Thyrohyoid | Oblique line of the thyroid cartilage | Lower border of the body and the greater cornu of the hyoid bone | Cervical spinal nerve 1 via the hypoglossal nerve |
| Omohyoid (superior belly) | Intermediate tendon | Hyoid bone | Superior root of ansa cervicalis (C1) |
| Omohyoid (inferior belly) | Superior border of scapula | Intermediate tendon | Ansa cervicalis (C1-C3) |
Nerve supplyEdit
All of the infrahyoid muscles are innervated by the ansa cervicalis from the cervical plexus (C1-C3)<ref>Template:Citation</ref><ref>Template:Citation</ref> except the thyrohyoid muscle, which is innervated by fibers only from the first cervical spinal nerve travelling with the hypoglossal nerve.<ref name=":0" />
FunctionEdit
The infrahyoid muscles function to elevate and depress the hyoid bone and larynx during swallowing and speech.<ref>Template:Citation</ref> This moves the larynx as one unit.<ref>Template:Citation</ref>