Orbital Fracture in Emergency Medicine
- Author: Thomas Widell, MD; Chief Editor: Rick Kulkarni, MD more...
Background
Orbit is composed of 7 facial bones: frontal, zygoma, maxilla, lacrimal, ethmoid, sphenoid and palatine.
- Superior orbital ridge and upper medial orbital ridge are part of the frontal bone.
- Lateral orbital rim is part of the zygoma.
- Inferior and lower medial rims are part of the maxilla. Floor of the orbit is made of the upper border of the maxillary sinus.
- Medial rim separating orbit from nares is the lacrimal bone.
- Medial wall and part of the posterior wall of the orbit are formed by the ethmoid bone.
- The rest of the posterior of the orbit is formed by the 2 wings of the sphenoid bone, the continuation of the lacrimal bone from the medial wall and orbital process of the palatine bone.
Optic nerve exits the optic foramen in the lesser wing of the sphenoid bone. Globe of the eye sits within the orbit surrounded with periorbital fat and the extraocular muscles that control its movement. Inferior orbital nerve courses through the maxilla in the orbital floor. Weakest portion of the orbit is the thin orbital floor (maxilla) and the lamina papyracea (ethmoid bone) medially and inferiorly.
Pathophysiology
Blow-out fractures occur when a blow to the eye increases pressure in the orbit, causing the weak floor or lamina papyracea to "blow out" into the maxillary sinus or ethmoid bone.[1, 2, 3, 4, 5, 6, 7] This results in a fracture, though it often prevents globe rupture and loss of the eye.[4] Periorbital fat and extraocular muscles can become entrapped in the fracture, leading to problems of ocular movement.[4] When the medial wall (lamina papyracea) is fractured, the medial rectus becomes entrapped, leading to lateral gaze dysfunction.
In maxillary fracture, the orbit floor blows out and inferior rectus entrapment leads to problems in upward gaze.[1, 2, 3, 4, 5, 6, 7] The eye can be injured during compression before the ethmoid bone or the maxillary sinus fractures. About one third of blow-out fractures have an associated eye injury.[4] Superior orbital rim fracture is a frontal bone fracture that is associated with high-impact injuries to the brain, face, and cervical spine.[8] Tripod fractures and zygomaticomaxillary complex fractures occur from high-impact injury to the cheek's malar eminence (zygoma). Often these fractures are associated with eye and inferior orbital nerve injuries.
Epidemiology
Mortality/Morbidity
The principal morbidity associated with orbital fractures is eye injury. Associated injuries include corneal abrasion, lens dislocation, iris disruption, choroid tear, scleral tear, ciliary body tear or bruise, retinal detachment and tear, hyphema, ocular muscle entrapment, and globe rupture.[4]
Sex
Males are at higher risk of eye injuries because of their increased incidence of trauma. In women, ask if the injury was from a partner or if they feel threatened by anyone, as the incidence of domestic violence and sexual assault is highly associated with this type of injury.
For more information, see Medscape's Trauma Resource Center.
Age
For all eye injuries, age distribution has 2 peaks: 10-40 years and older than 70 years.
Hendler BH. Maxillofacial trauma. In: Rosen P, ed. Emergency Medicine: Concepts and Clinical Practice. Mosby-Year Book; 1998:1093-1103.
McGill J, Ling LJ, Taylor S. Facial trauma. In: Diagnostic Radiology in Emergency Medicine. Mosby-Year Book; 1992:51-76.
Smith RG. Maxillofacial injuries. In: Harwood-Nuss A, ed. The Clinical Practice of Emergency Medicine. Lippincott Williams & Wilkins Publishers; 1996:408-418.
Spoor TC, Ramocki JM, Kwito GM. Ocular trauma. In: Wilson RF, Walt AJ, eds. Management of Trauma: Pitfalls and Practice. 2nd ed. Lippincott, Williams & Wilkins; 1996:225-241.
Sullivan WG. Trauma to the face. In: Wilson RF, Walt AJ, eds. Management of Trauma: Pitfalls and Practice. Lippincott, Williams & Wilkins; 1996:242-269.
Hasan N, Colucciello SA. Maxillofacial trauma. In: Tintinalli JE, Gabor KD, Stapczynski SJ, eds. Emergency Medicine: A Comprehensive Study Guide. 6th ed. McGraw-Hill Co Inc; 2004:chap 257, p1583-1.
McKay MP. Facial trauma. In: Marx JA, Hockberger RS, Walls RM, eds. Rosen's Emergency Medicine, Concepts and Clinical Practice. Vol 1. 6th ed. Philadelphia, PA: Mosby Elsevier; 2006:382-98/chap 39.
Snell RS, Smith MS. The face, scalp, and mouth. In: Clinical Anatomy for Emergency Medicine. Mosby-Year Book; 1993:206-241.
Glynn SM, Asarnow JR, Asarnow R, et al. The development of acute post-traumatic stress disorder after orofacial injury: a prospective study in a large urban hospital. J Oral Maxillofac Surg. Jul 2003;61(7):785-92. [Medline].
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