Uncinate Process

Description

Uncinate processes of the ethmoid form thin, sickle shaped laminae along the anteromedial aspect of the ethmoidal labyrinth. Each uncinate process descends inferiorly from the ethmoid bone on the lateral wall of the nasal cavity, lying medial to the orbit and lamina papyracea and lateral to the middle nasal concha. The free posterior margin creates a curved ridge that helps define the hiatus semilunaris, with the ethmoidal bulla positioned posterosuperiorly and the ethmoidal infundibulum tracking superolaterally toward the frontal recess and anterior ethmoidal air cells. Otolaryngologists focus on this structure because it is a gatekeeper for the osteomeatal complex, where subtle anatomic variation in the attachment of the uncinate process can redirect drainage from the maxillary sinus and frontal sinus and contribute to chronic rhinosinusitis. A common surgical step in functional endoscopic sinus surgery is uncinectomy, performed to expose the natural maxillary ostium and open the infundibulum while protecting the lamina papyracea laterally and the nasolacrimal duct anteriorly. Fine bony thickness and the hook-like contour are emphasized, which helps you explain how a narrow cleft between the uncinate process and bulla can become obstructed by mucosal edema or polyposis. Use this illustration in head and neck anatomy teaching on the lateral nasal wall, in ENT board-review figures on the osteomeatal unit, or in surgical atlases describing uncinectomy and maxillary antrostomy landmarks. It also suits radiology education when correlating coronal CT anatomy of the infundibulum, hiatus semilunaris, and adjacent ethmoid air cells. Anatomical accuracy verified by SciePro's Medical Advisory Board.