The thyrohyoid muscle is a small

skeletal muscle Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of m ...

on the

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 ...

. It originates from the lamina of the thyroid cartilage, and inserts into the

greater cornu 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 vertebra ...

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 is supplied by the

hypoglossal nerve The hypoglossal nerve, also known as the twelfth cranial nerve, cranial nerve XII, or simply CN XII, is a cranial nerve that innervates all the extrinsic and intrinsic muscles of the tongue except for the palatoglossus, which is innervated ...

, and a branch of the

ventral rami The ventral ramus (pl. ''rami'') (Latin for ''branch'') is the anterior division of a spinal nerve. The ventral rami supply the antero-lateral parts of the trunk and the limbs. They are mainly larger than the dorsal rami. Shortly after a spinal ...

of the

cervical plexus The cervical plexus is a plexus of the anterior rami of the first four cervical spinal nerves which arise from C1 to C4 cervical segment in the neck. They are located laterally to the transverse processes between prevertebral muscles from the me ...

, spinal nerve C1, which travels with the hypoglossal nerve. The thyrohyoid muscle depresses the

and elevates the

larynx The larynx (), commonly called the voice box, is an organ in the top of the neck involved in breathing, producing sound and protecting the trachea against food aspiration. The opening of larynx into pharynx known as the laryngeal inlet is about ...

. By controlling the position and shape of the larynx, it aids in making sound.

Structure

The thyrohyoid muscle is a

quadrilateral In geometry a quadrilateral is a four-sided polygon, having four edges (sides) and four corners (vertices). The word is derived from the Latin words ''quadri'', a variant of four, and ''latus'', meaning "side". It is also called a tetragon, ...

muscle in shape. It appears like an upward continuation of the sternothyroid muscle. It belongs to the infrahyoid muscles group. It lies in the

carotid triangle The carotid triangle (or superior carotid triangle) is a portion of the anterior triangle of the neck. Coverings and boundaries It is bounded: * Posteriorly by the anterior border of the Sternocleidomastoid; * Anteroinferiorly, by the superior bel ...

. It arises from the oblique line on the lamina of the

thyroid cartilage The thyroid cartilage is the largest of the nine cartilages that make up the ''laryngeal skeleton'', the cartilage structure in and around the trachea that contains the larynx. It does not completely encircle the larynx (only the cricoid cartilage ...

. It is inserted into the lower border of the

of the

Nerve supply

The thyrohyoid muscle is supplied by the

(XII). It is the only infrahyoid muscle that is not 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. Bra ...

. It is also supplied by the thyrohyoid branch of cervical spinal nerve 1 (C1). This is via the

. This nerve branches from the first

cervical nerve A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into the ...

as it joins the

for a short distance.

Function

The thyrohyoid muscle depresses the

and elevates the

and the

, drawing them together. By controlling the position and shape of the larynx, it aids in making sound.

Other animals

The thyrohyoid muscle is found in many other animals, including

horses The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million ...

Additional images

File:Gray186.png, Hyoid bone. Anterior surface. Enlarged. File:Gray560.png, The veins of the thyroid gland. File:Gray794.png, Hypoglossal nerve, cervical plexus, and their branches. File:Gray808.png, The right brachial plexus with its short branches, viewed from in front. File:Gray957.png, Side view of the larynx, showing muscular attachments. File:Slide8e.JPG, Thyrohyoid muscle

References

External links

* * *
PTCentral
{{Authority control Muscles of the head and neck

Structure

Nerve supply

Function

Other animals

Additional images

See also

References

External links