A "blow-out fracture" involves which of the following structures?

A "blow-out fracture" specifically involves the floor of the orbit, which is the bony structure that supports the eye. This type of fracture typically occurs when a blunt force trauma, such as a punch or an object striking the eye, creates a pressure wave that causes a fracture to the thin bones comprising the bottom of the eye socket.

In a blow-out fracture, the impact can lead to a displacement of the orbital floor, allowing for the possibility of herniation of the surrounding tissue into the sinus cavity below, often resulting in ocular imaging concerns and potential vision problems. The association with the floor of the orbit is crucial, as this structure is particularly vulnerable due to its thinness compared to other surrounding facial bones.

Other structures mentioned, such as the maxilla, nasal cavity, and zygomatic arch, while potentially involved in facial fractures, do not define the specific injury characteristic of a blow-out fracture. Therefore, focusing on the floor of the orbit is essential for understanding the nature of this particular type of fracture.