|4th and 6th branchial arch|
The arytenoid (//)cartilages are a pair of small three-sided pyramids which form part of the larynx, to which the vocal folds (vocal cords) are attached. These allow and aid in the vocal cords' movement.
The posterior surface is a triangular, smooth, concave, and gives attachment to the Arytænoidei obliquus and transversus.
The antero-lateral surface is somewhat convex and rough. On it, near the apex of the cartilage, is a rounded elevation (colliculus) from which a ridge (crista arcuata) curves at first backward and then downward and forward to the vocal process. The lower part of this crest intervenes between two depressions or foveæ, an upper, triangular, and a lower oblong in shape; the latter gives attachment to the Vocalis muscle.
Base and apex
The base of each cartilage is broad, and on it is a concave smooth surface, for articulation with the cricoid cartilage.
- Its lateral angle is called the muscular process
- Its anterior angle is called the vocal process
The apex of each cartilage is pointed, curved backward and medialward, and surmounted by a small conical, cartilaginous nodule, the corniculate cartilage.
They allow the vocal folds to be tensed, relaxed, or approximated.
The arytenoids articulate with the supero-lateral parts of the cricoid cartilage lamina, forming the cricoarytenoid joints at which they can come together, move apart, tilt anteriorly or posteriorly, and rotate.