Larynx: action of vocalis and thryoarytenoid muscles (Latin)

The musculus thyroarytenoideus is a wide, paired muscle arising from the facies interna of cartilago thyroidea, near the midline, as well as the ligamentum cricothyroideum. Its fibers pass posterolaterally to insert into the facies anterolateralis of the cartilago arytenoidea. The musculus vocalis is a small, paired strand-like muscle which sits parallel to the ligamentum vocale. It originates at the lateral surface of the processus vocalis of the cartilago arytenoidea, runs anteromedially across the aditus laryngis and attaches to the anterior part of the ipsilateral ligamentum vocale near the cartilago thyroidea. The m. thyroarytenoideeus and m. vocalis both draw the cartilagines arytenoideae anteriorly allowing the ligg. vocales to shorten, thicken and relax. This means they play a crucial part in controlling and changing the tonal quality of the voice. Concurrently, both muscles rotate the cartilagines arytenoideae medially which helps in closing the rima glottidis. The narrow/wedge-shaped appearance of the rima glottidis in this image represents that seen during normal respirations (‘resting’ position).