Table of Contents
- 1 What is the origin of the Thyroarytenoid muscle?
- 2 Where is the Thyroarytenoid muscle located?
- 3 What are the two parts of the Thyroarytenoid muscle?
- 4 What is the function of the Vocalis?
- 5 What does the thyroarytenoid muscle do during phonation?
- 6 What does the Thyroepiglottic do?
- 7 What is the Vocalis muscle?
- 8 What happens when the Thyroarytenoid muscle contracts?
- 9 Where does the thyroarytenoid muscle originate?
- 10 What is the superior portion of the thyroarytenoid?
- 11 What is the direction of the muscle fibers?
What is the origin of the Thyroarytenoid muscle?
Thyroarytenoid muscle
| Origin | Angle of thyroid cartilage and adjacent cricothyroid ligament |
|---|---|
| Insertion | Anterolateral surface of arytenoid cartilage |
| Action | Draws arytenoid cartilages anteriorly, Relaxes vocal ligament (for low pitch sound) |
| Innervation | Inferior laryngeal nerve (of recurrent laryngeal nerve (CN X)) |
Where is the Thyroarytenoid muscle located?
It arises in front from the lower half of the angle of the thyroid cartilage, and from the middle cricothyroid ligament. Its fibers pass backward and laterally, to be inserted into the base and anterior surface of the arytenoid cartilage.
What is the origin of the Thyroepiglottic?
The thyroepiglottic muscle originates on the internal surface of the thyroid cartilage and inserts on the margin of the epiglottis. When contracting, this muscle inferiorly displaces the epiglottis. These muscles work synergistically to close the laryngeal inlet by pulling the epiglottis posteriorly and inferiorly.
What are the two parts of the Thyroarytenoid muscle?
The muscular part of the vocal folds consists of 2 parts. The external part is called the thyroarytenoid muscle and the internal part is called the vocalis muscle.
What is the function of the Vocalis?
Similar to a rubber band, lengthening of the vocal folds also ‘thins’ them, while shortening of the vocal folds ‘thickens’ them. Thus the general action of vocalis is to shorten, and thicken, the vocal folds and thereby change the tonal quality of the voice.
Is Thyroarytenoid a tensor?
The thyroarytenoid muscle exhibits higher passive tension when generating maximal isometric tension than the digastric muscle control group. We conclude that these findings are related to the ability of the thyroarytenoid muscle to function as a fine tensor of the vocal fold in a high strain environment.
What does the thyroarytenoid muscle do during phonation?
The vocal folds are adducted by contractions of the interarytenoid, lateral cricoarytenoid and TA muscles during vocalization. These muscles control the degree of glottic narrowing. The TA muscle also increases the stiffness of vocal folds.
What does the Thyroepiglottic do?
Anatomical terms of muscle They have received a distinctive name, thyroepiglotticus or thyroepiglottic muscle, and are sometimes described as a separate muscle. This muscle’s function is to widen the laryngeal inlet.
What happens when the thyroarytenoid muscle contracts?
As it contracts it approximates the cricoid and the thyroid cartilages anteriorly, increasing the distance between the attachments of the cords, and thus lengthens them. The thyroarytenoid muscle lying in the cord shortens the cord.
What is the Vocalis muscle?
Vocalis Muscle The vocalis is an intrinsic laryngeal muscle comprised of fibers from the thyroarytenoid muscle. It runs parallel and attaches directly to the vocal ligament. It originates on the interior surface of the thyroid cartilage and inserts on the vocal process of the arytenoid cartilage.
What happens when the Thyroarytenoid muscle contracts?
What does the Interarytenoid do?
The IA (interarytenoid) muscle holds the vocal cords in a closed position after the LCA muscles bring them together. The IA muscle from one side attaches with the IA muscle from the other side.
Where does the thyroarytenoid muscle originate?
Thyroarytenoid muscle arises from the inner surface of the inferior part of thyroid cartilage, near the midline, as well as cricothyroid ligament. Its fibers pass posterolaterally to insert into the anterolateral surface of the arytenoid cartilage.
What is the superior portion of the thyroarytenoid?
Some anatomists describe the superior portion of thyroarytenoid as a separate muscle called the vocalis muscle, the medial border of which is associated with the vocal ligament. Some thyroarytenoid muscle fibers help to form the muscular layer of the vocal cords.
What is the function of the cricothyroid?
The cricothyroid muscle, which rotates the major laryngeal cartilages, in turn passively stretches and tightens the vocal folds. As they lengthen and become stiffer, the fundamental frequency of vocal fold vibration increases and a higher-pitched sound is produced. The thyroarytenoid muscle, conversely, shortens the vocal fold by contracting.
What is the direction of the muscle fibers?
The direction of the muscle fibers and fascicles are used to describe muscles. For example, the abdominal muscles all indicated the direction of the fibers such as the rectus (straight), the obliques (at an angle) and the transverse (horizontal) muscles of the abdomen. Some muscle names indicate the number of muscles in a group.