Muscles of the Larynx

Question 1

Cricothyroid

Answer 1

Origin: anterior and lateral aspects of arch of cricoid cartilage

Insertion: inferior margin and inferior horn of thyroid cartilage

Innervation: external branch of superior laryngeal n. (CN X)

Action: stretches vocal folds, increases pitch of the voice

Question 2

Posterior Cricoarytenoid

Answer 2

Origin: posterior surface of lamina of cricoid cartilage

Insertion: muscular process of arytenoid cartilage

Innervation: inferior laryngeal n. (CN X)

Action: abducts vocal fold, opens airway more to faciliate breathing

Question 3

Lateral Cricoarytenoid

Answer 3

Origin: superior border of arch of cricoid cartilage

Insertion: muscular process of arytenoid process

Innervation: inferior laryngeal n. (CN X)

Action: adducts vocal fold, closes airway partially or completely depending on the actions of other muscles

Question 4

Thyroarytenoid

Answer 4

Origin: posterior surface of thyroid cartilage at midline angle

Insertion: anterolateral border and vocal process of arytenoid process

Innervation: inferior laryngeal n. (CN X)

Action: relaxes vocal fold, lowers pitch of the voice

Question 5

Transverse and Oblique Arytenoid

Answer 5

Origin: one arytenoid cartilage

Insertion: opposite arytenoid cartilage

Innervation: inferior laryngeal n. (CN X)

Action: closes intercartilaginous portion of rima glottidis, important for coughing

Question 6

Vocalis

Answer 6

Origin: vocal process of arytenoid cartilage

Insertion: vocal ligaments

Innervation: inferior laryngeal n. (CN X)

Action: fine tunes tension of vocal ligament, affects pitch of the voice