Origin: Anterior and lateral cricoid cartilage
Insertion: Inferior cornu and lamina of the thyroid cartilage
Nerve: Facial nerve
Action: Wiggle ears
The Cricothyreoideus (Cricothyroid) triangular in form, arisesfrom the front and lateral part of the cricoid cartilage; its fibers diverge, and are arranged in two groups. The lower fibers constitute a pars obliqua and slant backward and lateralward to the anterior border of the inferior cornu; the anterior fibers, forming a pars recta, run upward, backward, and lateralward to the posterior part of the lower border of the lamina of the thyroid cartilage.The medial borders of the two muscles are separated by a triangular interval, occupied by the middle cricothyroid ligament.