The sternohyoid muscle is a thin, narrow muscle attaching the
hyoid bone
The hyoid bone (lingual bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies between the base of the mandible and the third cervical verteb ...
to the
sternum
The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. ...
. It is one of the paired
strap muscles of the
infrahyoid muscles. It is supplied by the
ansa cervicalis
The ansa cervicalis (or ansa hypoglossi in older literature) is a loop of nerves that are part of the cervical plexus. It lies superficial to the internal jugular vein in the carotid triangle. Its name means "handle of the neck" in Latin.
Branc ...
. It depresses the hyoid bone.
Structure
The sternohyoid muscle is one of the paired
strap muscles of the
infrahyoid muscles. It arises from the posterior border of the medial end of the
clavicle
The clavicle, or collarbone, is a slender, S-shaped long bone approximately 6 inches (15 cm) long that serves as a strut between the shoulder blade and the sternum (breastbone). There are two clavicles, one on the left and one on the rig ...
, the
posterior sternoclavicular ligament, and the upper and posterior part of the
manubrium
The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. Sh ...
of the
sternum
The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. ...
.
Passing upward and medially, it is inserted by short
tendinous fibers into the lower border of the body of the
hyoid bone
The hyoid bone (lingual bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies between the base of the mandible and the third cervical verteb ...
.
It runs lateral to the
trachea
The trachea, also known as the windpipe, is a cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all air-breathing animals with lungs. The trachea extends from th ...
.
Nerve supply
The sternohyoid muscle is supplied by a branch of the
ansa cervicalis
The ansa cervicalis (or ansa hypoglossi in older literature) is a loop of nerves that are part of the cervical plexus. It lies superficial to the internal jugular vein in the carotid triangle. Its name means "handle of the neck" in Latin.
Branc ...
.
Variations
The sternohyoid muscle may be doubled, have accessory slips (Cleidohyoideus) or be completely absent in some people.
It sometimes presents a transverse
tendinous inscription immediately above its origin.
Function
The sternohyoid muscle performs a number of functions:
* depresses the
hyoid bone
The hyoid bone (lingual bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies between the base of the mandible and the third cervical verteb ...
.
* helps with
speech
Speech is a human vocal communication using language. Each language uses phonetic combinations of vowel and consonant sounds that form the sound of its words (that is, all English words sound different from all French words, even if they are th ...
,
primarily to do with
volume
Volume is a measure of occupied three-dimensional space. It is often quantified numerically using SI derived units (such as the cubic metre and litre) or by various imperial or US customary units (such as the gallon, quart, cubic inch). Th ...
rather than
intonation.
* helps to move the
head
A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals may no ...
and
neck
The neck is the part of the body on many vertebrates that connects the head with the torso. The neck supports the weight of the head and protects the nerves that carry sensory and motor information from the brain down to the rest of the body. In ...
.
Additional images
File:Gray116.png, Posterior surface of sternum.
File:Gray201.png, Left clavicle. Inferior surface.
File:Gray186.png, Hyoid bone. Anterior surface. Enlarged.
File:Gray384.png, Section of the neck at about the level of the sixth cervical vertebra.
File:Gray390.png, Posterior surface of sternum and costal cartilages, showing Transversus thoracis.
File:Gray562.png, The fascia and middle thyroid veins. The veins here designated the inferior thyroid are called by Kocher the thyroidea ima.
File:Anterior region of neck (9).JPG, Sternohyoid muscle
File:Slide4cc.JPG, Sternohyoid muscle
File:Slide3b.JPG, Sternohyoid muscle
File:Slide5c.JPG, Sternohyoid muscle - lateral view
File:Slide12d.JPG, Sternohyoid muscle - right view
File:Slide1g.JPG, Sternohyoid muscle
File:Slide2deded.JPG, Muscles, nerves and arteries of neck.Deep dissection. Anterior view.
References
External links
* - "Nerves and Vessels of the
Carotid triangle"
PTCentral
{{Authority control
Muscles of the head and neck