Infrahyoid muscles

Infrahyoid muscles
File:Infrahyoid muscles.png
Muscles of the neck. Anterior view. Hyoid bone is white horizontal line near top. Infrahyoid muscles are below hyoid, while Suprahyoid muscles are above. "Sterno-hyoideus" is at center right. "Omo-hyoideus" is immediately to the right of the Sterno-hyoideus. "Thyro-hyoideus" is to the right of omo-hyoideus, across from thyroid cartilage. "Sterno-thyreoidus" is at left, below thyro-hyoideus.
Latin	musculi infrahyoidei
Gray's	subject #112 393
Origin
Insertion
Artery:
Nerve:	ansa cervicalis
Action:	depress hyoid bone
Dorlands /Elsevier	m_22/12549354

The infrahyoid muscles are a group of four pairs of muscles in the anterior part of the neck. (The term infrahyoid refers to the region below (inferior) to the hyoid bone in the neck. )

Collectively, they are referred to as the strap muscles, because the muscles are long and flat much like a strap.

Individual muscles

Namely, the muscles are:

Muscle	Origin	Insertion
sternothyroid	sternum	thyroid cartilage
sternohyoid	sternum	hyoid bone
thyrohyoid	thyroid cartilage	hyoid bone
omohyoid	superior border of scapula	hyoid bone

Innervation

All of the infrahyoid muscles are innervated by the ansa cervicalis from the cervical plexus(C1-3) EXCEPT for the thyrohyoid muscle, which is innervated by only C1.

The stylopharyngeus muscle is considered by many to be one of the strap muscles, but it is innervated by CN9 rather than the ansa cervicalis.

Action

These four muscles also known as the "strap" muscles function is to depress the hyoid bone and larynx during swallowing and speaking

See also

• Muscular triangle
• Suprahyoid muscles

it:Muscoli sottoioidei