Which intrinsic muscle of the larynx is solely responsible for abduction of the vocal cords?
- A Posterior cricoarytenoid ✓
- B Interarytenoid
- C Lateral cricoarytenoid
- D Cricothyroid
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 cords. It is the single abductor of the larynx, so its bilateral paralysis causes airway obstruction. The lateral cricoarytenoid and interarytenoid adduct, while the cricothyroid lengthens and tensions the cords rather than moving them apart.
Reference: Gray's Anatomy for Students, 4th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.