Anatomy of the Condition
The vocal folds are inside the larynx or voice box. These structures open for breathing. They come together during swallowing. They vibrate as air passes between them during speaking or singing. Fine layers with a soft outer cover make up the vocal folds. A stiffer ligament lies below the thyroarytenoid muscle connects deep to the ligament. The thyroarytenoid muscle makes up the bulk of the vocal fold.
When one or both of the vocal folds become atrophied or weak, a gap forms between the vocal folds. This causes vocal fold bowing. It prevents them from closing completely and vibrating as they should.