Which of the following is the only intrinsic laryngeal muscle responsible for abduction of the vocal cords?
- A Lateral cricoarytenoid
- B Thyroarytenoid
- C Posterior cricoarytenoid ✓
- D Transverse arytenoid
Correct answer: C. Posterior cricoarytenoid
Explanation
The posterior cricoarytenoid arises from the posterior surface of the cricoid lamina and inserts into the muscular process of the arytenoid, rotating it laterally to abduct the cord. It is the sole abductor, which is why its bilateral loss causes life-threatening airway obstruction. The lateral cricoarytenoid, thyroarytenoid and transverse arytenoid are all adductors, closing the glottis during phonation and swallowing.
Reference: Gray's Anatomy, 42nd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.