Inferior Orbital Floor Fracture

The infraorbital vessels are found in the inferior orbital fissure and travel down the infraorbital groove into the infraorbital canal and exit through the infraorbital foramen.

Inferior orbital floor fracture.

Fractures of the orbital floor are common. An orbital blowout fracture is a traumatic deformity of the orbital floor or medial wall typically resulting from impact of a blunt object larger than the orbital aperture or eye socket. Blowout fractures can occur through one or more of the orbital walls. The causes of orbital fractures vary but assault is the most frequent.

There also may be redness and patches of bleeding on the sclera the white part of the eye and on the eyelids inner lining. Lateral to the orbital canal lies the superior orbital fissure housing cranial nerves iii iv v and vi. Inferior blowout fractures are the most common. Orbital floor fracture can either be direct or indirect where direct involves the orbital rim while indirect are exclusive to the orbital floor.

Inferior blowout fractures involving the floor of the orbit maxillary sinus roof are the most common followed by medial wall blowout fractures. Symptoms of orbital fracture depend on the severity and location of the fracture and comprise of. Orbital fat prolapses into the maxillary sinus and may be joined by prolapse of the inferior rectus muscle. Most commonly the inferior orbital wall i e.

In either case if the intraorbital pressure is great enough at the time of injury orbital contents can be forced into the fracture site and possibly into the maxillary sinus. Fracture of the orbital floor also known as a blow out fracture can result in entrapment of the inferior rectus muscle limiting upward gaze. It is formed by the sphenoid bone and maxilla. The comparatively thin bone of the floor of the orbit.

Although the bone forming the medial wall is thinnest it is buttressed by the bone separating the ethmoidal air cells. 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. The main demographic characteristic that presents with this type of injury is the involvement of young men 2. Other causes include motor vehicle crash falls especially in the elderly sports and industrial accidents.

Inferior floor medial wall lamina papyracea superior roof lateral wall. The floor is likely to collapse because the bones of the roof and lateral walls are robust. Another theory is that compression of the inferior orbital rim causes direct buckling of the orbital floor. Orbital floor fractures offs occur frequently mainly in the context of trauma from physical altercations or road traffic accidents 1.

True blowout fractures result from a rapid increase in intraorbital pressure resulting in a herniation of orbital contents out through the thin bony orbital walls. A blowout fracture of the orbital floor is defined as a fracture of the orbital floor in which the inferior orbital rim is intact.