Cervical sinus

During human embryogenesis, the mandibular arch and hyoid arch grow more rapidly than those behind them, with the result that the latter become, to a certain extent, telescoped within the former, and a deep depression, the cervical sinus, is formed on either side of the neck.

Cervical sinus
Scheme of the pharyngeal arches I–IV: pharyngeal arches 1–4: pharyngeal pouches (inside) and/or pharyngeal grooves (outside) a: Tuberculum laterale b: Tuberculum impar c: Foramen cecum d: Ductus thyreoglossus e: Sinus cervicalis
Details
Identifiers
Latin	sinus cervicalis
Anatomical terminology

This sinus is bounded in front by the hyoid arch, and behind by the thoracic wall; it is ultimately obliterated by the fusion of its walls.

Sometimes, it can remain anterior to the sternocleidomastoid muscle. It can communicate with the skin (external cervical fistula) or with the pharynx (internal cervical fistula). It is prone to infection.