What is the innervation of the laryngeal muscles and which nerves supply them?

Innervation of the laryngeal muscles is provided by branches of the vagus nerve: the superior laryngeal and recurrent laryngeal nerves. The external branch of the superior laryngeal nerve innervates the cricothyroid muscle. Motor innervation of all other intrinsic laryngeal muscles is supplied by the recurrent laryngeal nerve (or its continuation, the inferior laryngeal nerve), which innervates the laryngeal muscles except for the cricothyroid.

Which laryngeal muscles perform the function of adducting the rima glottidis?

The reference notes that laryngeal muscles are functionally divided into adductors and abductors of the rima glottidis, though a specific list of adductor muscles is not detailed here.

What is the blood supply to the muscles of the larynx?

The larynx receives blood from the superior and inferior laryngeal arteries: the superior laryngeal artery (a. laryngea superior) branches from the superior thyroid artery (a. thyroidea superior), while the inferior laryngeal artery (a. laryngea inferior) branches from the inferior thyroid artery (a. thyroidea inferior).

What type of muscle tissue forms the muscles of the larynx?

All laryngeal muscles are exclusively striated. There are no smooth or mixed fibers present.

Which laryngeal muscle is responsible for abducting the rima glottidis?

This function is performed by only one muscle—the posterior cricoarytenoid muscle (m. cricoarytenoideus posterior).

What is the function of the cricothyroid muscle (m. cricothyroideus)?

The cricothyroid muscle belongs to the group of muscles that tense the vocal cords.

How are the muscles of the larynx classified based on their local action?

They are divided into extrinsic muscles that move the larynx as a whole and intrinsic muscles that change the positions of individual cartilages.

Home › Human Anatomy › Muscles of the Larynx

Muscles of the Larynx

Musculi laryngis

For medical students2 min readUpdated 2026-10-10

The muscles of the larynx form a complex group of striated muscle fibers that provide organ mobility and vocal fold function. Their coordinated action changes the width of the rima glottidis and regulates vocal cord tension for phonation.

Tissue TypeExclusively striated muscle tissue

Unique FunctionPosterior cricoarytenoid muscle is the sole abductor of the rima glottidis

Two CategoriesExtrinsic (move the entire larynx) and intrinsic (move the cartilages)

Histological Structure and Basic Classification

Morphologically, all laryngeal muscles are formed by striated muscle tissue. Students sometimes mistakenly choose smooth, cardiac, or mixed muscle variants on exams, but it is important to remember that laryngeal musculature is strictly striated.

Topographically and biomechanically, the entire muscular apparatus of the larynx is divided into two major categories:

Extrinsic muscles, which move the larynx as a whole (responsible for elevating and depressing the entire organ).
Intrinsic muscles of the larynx, whose function is to alter the relative positions of individual laryngeal cartilages.

Functional Division of Vocal Apparatus Muscles

The function of the vocal apparatus (glottis) is maintained by intrinsic muscles. Based on their vector of action, they are strictly divided into distinct groups. The primary classification reference is their effect on the rima glottidis and vocal cords (not to be confused with the laryngeal inlet, vestibule, or infraglottic cavity).

There are four functional groups:

Adductors of the rima glottidis (constrictors).
Abductors of the rima glottidis (dilators).
Tensors of the vocal cords.
Relaxers of the vocal cords.

Key Muscles of the Larynx

Among the most critical intrinsic muscles controlling the cartilages and vocal cords are:

Posterior cricoarytenoid muscle (m. cricoarytenoideus posterior). This is the most critical muscle for respiration, as it is the only muscle that abducts and widens the rima glottidis.
Lateral cricoarytenoid muscle (m. cricoarytenoideus lateralis).
Transverse arytenoid muscle (m. arytenoideus transversus).
Vocalis muscle (m. vocalis).
Cricothyroid muscle (m. cricothyroideus). The main function of this muscle is to tense the vocal cords.

Mnemonic

To easily remember their functions, keep in mind: 'Posterior is open.' The posterior cricoarytenoid muscle (m. cricoarytenoideus posterior) is the sole dilator that widens the rima glottidis.

Frequently asked questions

What is the innervation of the laryngeal muscles and which nerves supply them?: Innervation of the laryngeal muscles is provided by branches of the vagus nerve: the superior laryngeal and recurrent laryngeal nerves. The external branch of the superior laryngeal nerve innervates the cricothyroid muscle. Motor innervation of all other intrinsic laryngeal muscles is supplied by the recurrent laryngeal nerve (or its continuation, the inferior laryngeal nerve), which innervates the laryngeal muscles except for the cricothyroid.
Which laryngeal muscles perform the function of adducting the rima glottidis?: The reference notes that laryngeal muscles are functionally divided into adductors and abductors of the rima glottidis, though a specific list of adductor muscles is not detailed here.
What is the blood supply to the muscles of the larynx?: The larynx receives blood from the superior and inferior laryngeal arteries: the superior laryngeal artery (a. laryngea superior) branches from the superior thyroid artery (a. thyroidea superior), while the inferior laryngeal artery (a. laryngea inferior) branches from the inferior thyroid artery (a. thyroidea inferior).
What type of muscle tissue forms the muscles of the larynx?: All laryngeal muscles are exclusively striated. There are no smooth or mixed fibers present.
Which laryngeal muscle is responsible for abducting the rima glottidis?: This function is performed by only one muscle—the posterior cricoarytenoid muscle (m. cricoarytenoideus posterior).
What is the function of the cricothyroid muscle (m. cricothyroideus)?: The cricothyroid muscle belongs to the group of muscles that tense the vocal cords.
How are the muscles of the larynx classified based on their local action?: They are divided into extrinsic muscles that move the larynx as a whole and intrinsic muscles that change the positions of individual cartilages.

Go deeper

Anatomy of the extrinsic muscles moving the larynx as a whole.
Mechanism of action of the lateral cricoarytenoid muscle.
Role of the transverse arytenoid muscle in closing the rima glottidis.
Structural features and functions of the vocalis muscle (m. vocalis).
The process of vocal cord relaxation and the muscles involved.