Anatomy of the uncinate process.

The uncinate process is a sickle-shaped, bony leaflet that descends from its anterosuperior attachment on the lateral nasal wall to its posteroinferior attachment on the inferior turbinate (figure). It also extends posteromedially to its free margin. Its concave posterosuperior free margin is parallel to the anterior surface of the ethmoid bulla. The uncinate process attaches to the perpendicular process of the palatine bone and the ethmoid process of the inferior turbinate with bony spicules.

The convex anterior margin ascends to the lacrimal bone and in some patients to the skull base or the lamina papyracea, remaining in contact with the bony lateral nasal wall. The uncinate process can attach to the middle turbinate superiorly when it is curved medially in its superiormost portion. In patients in whom it is curved medially to a greater extent than usual, the free margin of the uncinate process can protrude into and sometimes in some patients even out of the middle nasal meatus.

From the Southern New England Ear, Nose, Throat, and Facial Plastic Surgery Group, New Haven, Conn., the Hospital of St. Raphael, New Haven, and the Section of Otolaryngology, Yale University School of Medicine, New Haven.

This article is adapted from Yanagisawa E. Atlas of Rhinoscopy: Endoscopic Sinonasal Anatomy and Surgery. San Diego: Singular Publishing Group, 2000.