orbital lamina of ethmoid bone

{{Infobox anatomy

| Name = Orbital lamina of ethmoid bone

| Latin = lamina orbitalis ossis ethmoidalis

| Image = File:Gray152.png

| Caption = Ethmoid bone from the right side. (Lamina papyracea visible at center left.)

| Image2 = File:Orbital_bones.png

| Caption2 = The seven bones which articulate to form the orbit. (Ethmoid is brown.)

| Width = 200

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The orbital lamina of ethmoid bone (or lamina papyracea or orbital lamina) is a smooth, oblong,{{Citation needed|date=July 2023}} paper-thin{{Cite book |last=Sinnatamby |first=Chummy S. |title=Last's Anatomy |vauthors= |publisher= |year=2011 |isbn=978-0-7295-3752-0 |edition=12th |pages=377}} bone plate{{Citation needed|date=July 2023}} which forms the lateral wall of the labyrinth of the ethmoid bone. It covers the middle and posterior ethmoidal cells, and forms a large part of{{Citation needed|date=July 2023}} the medial wall of the orbit.

It articulates above with the orbital plate of the frontal bone, below with the maxilla and the orbital process of palatine bone, in front with the lacrimal, and behind with the sphenoid.{{Citation needed|date=July 2023}}

Its name lamina papyracea is an appropriate description, as this part of the ethmoid bone is paper-thin and fractures easily. A fracture here could cause entrapment of the medial rectus muscle.{{Citation needed|date=July 2023}}