Posterior Lacrimal Crest Of The Lacrimal Bone

Description

Posterior lacrimal crest on the lacrimal bone forms a sharp vertical ridge along the medial wall of the orbit, immediately posterior to the lacrimal fossa that houses the lacrimal sac. Medially, the crest contributes to the bony boundary between the orbit and the nasal cavity, while laterally it faces the orbital contents and lies anterior to the ethmoid air cells. Superiorly it approaches the frontolacrimal suture near the medial orbital rim, and inferiorly it continues toward the entrance of the nasolacrimal canal, where the lacrimal sac transitions into the nasolacrimal duct. Adjacent articulations with the frontal bone, maxilla, and ethmoid help frame the anterior lacrimal crest (maxilla) and the posterior lacrimal crest (lacrimal bone) as paired landmarks in the skeleton of the face and skull. Clinically, this crest matters because it defines the posterior margin of the lacrimal sac groove, a reference point in evaluation and surgery for nasolacrimal duct obstruction and dacryocystitis. During external dacryocystorhinostomy, surgeons create a bony ostium at the medial orbit and must respect the posterior lacrimal crest and nearby thin lamina papyracea to avoid unintended entry into ethmoid cells and to keep the dissection centered on the lacrimal sac. Bone is unforgiving. Educators will find this illustration well suited for teaching orbital anatomy in gross anatomy and head and neck courses, and for medical publishing on lacrimal drainage procedures, facial skeleton landmarks, and the osteology of the orbit. It also supports ophthalmology and ENT clinical materials that need an accurate, labeled reference for the posterior lacrimal crest, lacrimal fossa, and nasolacrimal canal relationships. Anatomical accuracy verified by SciePro's Medical Advisory Board.