Cricothyroid (Straight Part) (Pars recta musculi cricothyroidei)
Educational content only — not medical advice.
Anatomy
The straight part of the cricothyroid is the vertical anterior component of the cricothyroid muscle. Arising from the anterior arch of the cricoid cartilage, its fibers ascend nearly vertically to insert into the lower margin of the thyroid cartilage lamina. It works in concert with the oblique part to pull the thyroid cartilage downward and forward, directly tightening the vocal folds.
Origin & insertion
From the anterior surface of the cricoid arch to the lower margin of the anterior half of the thyroid cartilage lamina.
Action
Pulls the anterior thyroid lamina downward toward the cricoid, tightening and lengthening the vocal folds.
Innervation
External branch of the superior laryngeal nerve (branch of vagus nerve, cranial nerve X).
Clinical notes
The anterior space between the right and left straight parts overlies the median cricothyroid ligament, the landmark site for emergency cricothyroidotomy in acute airway obstruction.
Related structures
Educational references
FAQ
What is the role of the Cricothyroid (Straight Part)?
The straight part of the cricothyroid is the vertical anterior component of the cricothyroid muscle. Arising from the anterior arch of the cricoid cartilage, its fibers ascend nearly vertically to insert into the lower margin of the thyroid cartilage lamina. It works in concert with the oblique part to pull the thyroid cartilage downward and forward, directly tightening the vocal folds.
Why is the Cricothyroid (Straight Part) clinically important?
The anterior space between the right and left straight parts overlies the median cricothyroid ligament, the landmark site for emergency cricothyroidotomy in acute airway obstruction.
Source & license
BodyParts3D, © The Database Center for Life Science licensed under CC Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/). license details