Which nerve provides motor innervation to most intrinsic muscles of the larynx, except the cricothyroid?

• A. Recurrent laryngeal nerve
• B. Superior laryngeal nerve
• C. Vagus nerve
• D. Glossopharyngeal nerve

Answer: (A)

Most intrinsic muscles of the larynx are motorized by the recurrent laryngeal nerve, a branch of the vagus. It travels up in the tracheoesophageal groove and enters the larynx to supply nearly all intrinsic muscles, enabling movements that position and tense the vocal folds and control the glottic opening. The cricothyroid, however, gets its motor supply from the external branch of the superior laryngeal nerve, another vagal branch, which specifically innervates this muscle that tilts and tensions the vocal cords. This arrangement explains why the recurrent laryngeal nerve is the primary motor conduit for most intrinsic laryngeal muscles.