blowout fracture
Pronunciation: BLOH-owt FRAK-chur
An orbital floor or medial wall fracture without involving the orbital rim.
Full Definition
A blowout fracture is a specific type of orbital fracture characterized by a break in the orbital floor or medial orbital wall while the orbital rim remains intact. This injury pattern typically results from blunt trauma causing a sudden increase in intraorbital pressure, leading to fracture at the weakest points of the orbital walls. Blowout fractures can trap orbital soft tissues, causing enophthalmos, diplopia, and restricted eye movement. Clinical signs include the 'teardrop sign' on imaging, infraorbital numbness, and potential visual disturbances. Treatment may be conservative for small fractures or require surgical reconstruction with bone grafts or implants for larger defects.
Usage
Usage note: Distinguish from orbital rim fractures; specify floor vs. medial wall involvement.
In Context
- "The CT scan revealed a large blowout fracture of the left orbital floor with muscle entrapment." — Radiology report
- "Surgical repair of the blowout fracture was delayed to allow swelling to subside." — Treatment plan