Bone
Ethmoid bone
Thin partitions between the nose, orbits and cranium
High-yield
Olfactory nerve filaments pass through the cribriform plate. Injury involving these filaments and the overlying dura may cause loss of smell and a cerebrospinal-fluid leak into the nose.
Overview
The ethmoid contributes to the upper nasal cavity, nasal septum and medial orbital walls. Its paired lateral masses contain air cells, while the cribriform plate forms part of the roof over the nose. Superior and middle nasal conchae project from it.
Reference facts
- Bone type
- Irregular cranial bone
- Key landmarks
- Cribriform plate, crista galli, perpendicular plate, ethmoidal air cells, and superior and middle nasal conchae
- Articulations
- Frontal, sphenoid and vomer; paired nasal, lacrimal, maxillary, palatine and inferior nasal concha bones
Clinical correlation
The thin lamina papyracea separates ethmoidal air cells from the orbit. Infection may cross this boundary, explaining the association between ethmoid sinusitis and orbital cellulitis.
Frequently asked questions
What type of bone is the ethmoid bone?
The ethmoid bone is an irregular cranial bone bone.
What does the ethmoid bone articulate with?
Frontal, sphenoid and vomer; paired nasal, lacrimal, maxillary, palatine and inferior nasal concha bones.
What are the key landmarks of the ethmoid bone?
Key landmarks of the ethmoid bone include the cribriform plate, crista galli, perpendicular plate, ethmoidal air cells, and superior and middle nasal conchae.