Which intrinsic muscle of the larynx is the sole abductor of the vocal cords?
- A Posterior cricoarytenoid ✓
- B Lateral cricoarytenoid
- C Thyroarytenoid
- D Transverse arytenoid
Correct answer: A. Posterior cricoarytenoid
Explanation
The posterior cricoarytenoid arises from the posterior surface of the cricoid lamina and inserts on the muscular process of the arytenoid, rotating it externally to abduct the cord. It is called the safety muscle of the larynx because its bilateral paralysis causes stridor and airway compromise. The lateral cricoarytenoid and transverse arytenoid are adductors, while the thyroarytenoid relaxes and shortens the cord.
Reference: Gray's Anatomy for Students, 4th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.