The transverse arytenoid is the only unpaired laryngeal muscle, crossing directly between the posterior surfaces of both arytenoids. It closes the interarytenoid space during phonation and swallowing.
| Origin | Lateral border of one arytenoid cartilage |
|---|---|
| Insertion | Lateral border of the opposite arytenoid cartilage — crossing transversely |
| Nerve Supply | Recurrent laryngeal nerve (CN X) |
| Blood Supply | Laryngeal branch of inferior thyroid artery |
| Actions | Adducts the arytenoid cartilages — closes the interarytenoid space; The only unpaired laryngeal muscle |
|---|
The transverse arytenoid is assessed during laryngoscopy — its contraction during phonation closes the posterior glottis. Presbylaryngis (age-related vocal fold atrophy) produces a posterior glottic gap even with intact RLN, from atrophy of both transverse and oblique arytenoid fibres.
Not externally palpable — assessed by laryngoscopy during phonation.
Age-related transverse arytenoid atrophy contributing to posterior glottic gap and the weak, breathy voice of presbylaryngis, managed by voice therapy or bilateral vocal fold injection augmentation.
