Superior Perspective of the Oblique Arytenoid Muscles

Description

Oblique arytenoid muscles (mm. arytenoidei obliqui) are shown from a superior laryngeal perspective as paired slips that arise from the muscular process of one arytenoid cartilage and cross superomedially to the apex of the contralateral arytenoid. Their decussating fibers form an X across the posterior aspect of the rima glottidis, lying superficial to the transverse arytenoid (m. arytenoideus transversus), which spans horizontally between the posterior surfaces of the arytenoid cartilages. At the superior margin, the oblique fibers continue as the aryepiglottic muscle within the aryepiglottic fold, coursing toward the lateral edge of the epiglottis. Midline posterior relations center on the interarytenoid region. Short and dense. Functionally, this view clarifies how the interarytenoid complex closes the posterior glottic chink during phonation and protective laryngeal closure, a distinction that matters when separating posterior glottic insufficiency from anterior vocal fold problems. The oblique arytenoid, together with the transverse arytenoid, is supplied by the recurrent laryngeal nerve, so unilateral recurrent laryngeal nerve palsy after thyroidectomy or anterior cervical spine surgery can leave a persistent posterior gap and breathy voice despite an otherwise mobile contralateral fold. Its continuation into the aryepiglottic fold also links posterior glottic adduction to sphincteric narrowing of the laryngeal inlet during swallowing. Useful for teaching intrinsic laryngeal musculature in head and neck anatomy, speech and hearing science, and otolaryngology rotation materials, and for illustrating surgical or endoscopic discussions of posterior glottic closure in vocal fold medialization or injection laryngoplasty. It also fits figures in anatomy atlases and review articles on recurrent laryngeal nerve injury and laryngeal electromyography targeting of interarytenoid activity. Anatomical accuracy verified by SciePro's Medical Advisory Board.