A 35-year-old singer presents with a breathy, whispering voice after a motor vehicle accident. Laryngoscopy shows the right vocal fold is paralysed in the abducted (paramedian) position. Examination reveals no other cranial nerve deficits. Which specific branch of which nerve is most likely injured?

• A External branch of superior laryngeal nerve
• B Internal branch of superior laryngeal nerve
• C Vagus nerve at the jugular foramen
• D Right recurrent laryngeal nerve ✓

Explanation

Recurrent laryngeal nerve (RLN) palsy causes the vocal cord to be paralysed in the paramedian (cadaveric) position — adducted slightly but not midline — resulting in an ineffective glottis and breathy voice. Complete vagal lesion above the origin of the superior laryngeal nerve causes the cord to lie in a more lateral (fully abducted) position and is associated with other CN X deficits. The external branch of SLN supplies only cricothyroid (pitch control, no cord position change); the internal branch is purely sensory.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.