Blow out fracture of orbit involves:

* Orbital floor fracture, also known as "blowout" fracture of the orbit. * Blow out fracture of orbit involves: 1. Fractures of the orbital floor are common: it is estimated that about 10% of all facial fractures are isolated orbital wall fractures (the majority of these being the orbital floor), and that 30-40% of all facial fractures involve the orbit. 2. The anatomy of the orbital floor predisposes it to fracture. 3. The inferior orbital neurovascular bundle (comprising the infraorbital nerve and aery) courses within the bony floor of the orbit; the roof of this infraorbital canal is only 0.23mm thick, and the bone of the posterior medial orbital floor averages 0.37 mm thick. 4. By contrast, the bone of the lateral poion of the orbital floor averages 1.25 mm thick, over 5 times the thickness of the bone over the neurovascular bundle. As one might suspect, it is this very thin area of the orbital floor overlying the neurovascular bundle where isolated orbital floor fractures invariably occur. REF : AK KHURANA 7TH ED