Muscles of larynx

Muscles of larynx

5. AN CRICOTHYROID

e MUSCLE

When the right and left cricothyroid muscles contract, they rotate

roid car the cricold at the cricothyroid joint.

+ Itis classically described as consisting of 2 bellies=—
attaches the lateral portion of
he antalo arch of the criceldcartlage to the Inarlor border This action brings the anterior arch of the cricoid superiorly toward
ie thyroid cartilage in a MAA ña ra bord the inferior border of the thyroid laminae while displacing the
also from the anterolateral border 4 osterior cricold lamina (and the arytenoid 0 s) inferiorly.
of the cricold arch travels obliquely upward to insert on the KS Donor ca late) A

ACTIONS: (
osa This inferior displacement increases the distance between the vocal
~ Stretches and tenses the vocal ligament and so is Important for ehr j し
the creation of forceful speech; Biomechanically, this translates 0
into a higher fundamental frequency produced by the vocal
folds
+ Italso has a role in altering the tone of voice (along with the ES
thyroarytenoid muscle), hence its colloquial name ‘SINGER'S 本
MUSCLE’ 06 (me

INNERVATION:
+ External laryngeal nerve (branch of superior laryngeal).

Right lateral view e of the vocal

the vocal fold. |