Infrahyoid muscles

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Infrahyoid muscles
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.

Contents

[edit] 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

[edit] 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.

[edit] Action

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

[edit] See also