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1997 Erlanger Health System Tennessee Craniofacial Center 1(800) 418-3223

Without treatment in a timelymanner, many individuals willdevelop future problems, theseverity and consequences ofwhich can be much greater than ifthe injury had been immediatelyrepaired. However, modern cran-iofacial surgical techniques cannow offer hope for patients withpre-existing post-traumatic facialdeformities despite considerabledelays between injury, diagnosis,and treatment. These innovativetechniques establish a higher stan-dard of care for the managementof facial injuries.

The following sections

describe the different areas andtypes of facial fractures:

ZYGOMATIC

FRACTURES

The zygomatic bone occupiesa prominent and important posi-tion in the facial skeleton. It playsa key role in determining facial

width as well as acting as a majorbuttress of the midface. Its anteri-or projection forms the malar emi-nence and is often referred to asthe malar bone. The zygoma hasseveral important articulations inthe midface. The zygoma forms asignificant portion of the floor andlateral wall of the orbit. In addi-tion, the zygoma meets the lateralskull to form the zygomatic arch.

The zygoma is the main but-tress between the maxilla and theskull; but in spite of its sturdiness,its prominent location makes itprone to fracture. The mechanismof injury usually involves a blowto the side of the face from a fist,

Front and lateral three dimensional CT Scans demonstratedisplaced fractures of all zygomatic buttresses.

Patient with a left displacedzygomatic fracture.

An open reduction with rigidminiplate fixation was performedwith postoperative result shown.

Zygomatic Fractures

object, or secondary to motor vehicle accidents. Moderateforce may result in minimally or nondisplaced fractures atthe suture lines. More severe blows frequently result ininferior, medial, and posterior displacement of the zygoma.

Comminuted fractures of the body with separation at thesuture lines are most often the result of high-velocity motorvehicle accidents. In general, displaced fractures willinvolve the inferior orbital rim and orbital floor, the zygo-maticofrontal suture, the zygomaticomaxillary buttress,and the zygomatic arch. Occasionally, however, a directblow to the arch will result in an isolated depressed fractureof the arch only.

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1997 Erlanger Health System Tennessee Craniofacial Center 1(800) 418-3223

Radiographic evaluation of the fractureis mandatory and may include both plainfilms and a computed tomographic (CT)scan. The CT scan has now essentiallyreplaced plain films as the gold standardin both evaluation and treatment planning.If physical findings and plain films are notsuggestive of a zygomatic fracture, the eval-uation may end here. However, if they dosuggest fracture, a coronal and axial CTscan should be obtained. The CT scan willaccurately reveal the extent of orbitalinvolvement, as well as degree of displace-ment of the fractures. This study is vital forplanning the operative approach.

Historically, closed reduction was themethod of choice for nearly all zygomatic

fractures. Multiple methods wereemployed, but most involved simply exert-ing pressure underneath the malar emi-nence and popping the fragments back intoalignment. Not only were these results fre-quently unsatisfactory, but they werefraught with complications including per-sistent diplopia, orbital dystopia, malunion,and significant residual deformity. In ourown experience, closed reductions yieldunpredictable results with significant

chance of relapse. We feel that plate andscrew fixation is now the standard of care.

The treatment of zygomatic fractures hasdramatically progressed over the past sev-eral decades from an entirely closedapproach to the more aggressive openreduction and rigid miniplate fixation oftoday. If a zygomatic fracture is displaced,we do an open reduction and rigid stabi-lization with mini-and microplates. Thefloor of the orbit is routinely explored andreconstructed, if needed, to restore orbitalvolume. The complications of an inade-quately or unreduced zygomatic fractureare very difficult to correct secondarily andusually avoidable. We feel that early diag-nosis combined with this aggressive surgi-cal treatment yields the best results.

MAXILLARY FRACTURES

The maxilla forms the largest component ofthe middle third of the facial skeleton. The maxil-la is a key bone in the midface that is closely asso-ciated with adjacent bones providing structuralsupport between the cranial base and the occlusalplane. Fractures of the maxilla occur less fre-quently than those of the mandible or nose due tothe strong structural support of this bone. Themidface consists of alternating thick and thin sec-tions of bone that are capable of resisting signifi-cant force. This structurally strong bone providesprotection for the globes and brain, projection ofthe midface, and support for occlusion.Reestablishing continuity of these buttresses is thefoundation on which maxillary fracture treatmentis based.

Renee LeFort (1901) provided the earliest clas-sification system of maxillary fractures. Hismodel described great lines of weakness in theface using low-velocity impact forces directedagainst cadaver skulls. Adiscussion of fractures ofthe maxilla would not be complete without adescription of LeForts work.

The Lefort I fracture, or transverse fracture,extends through the base of the maxillary sinuses

above the teeth apices essentially separating thealveolar processes, palate, and pterygoid process-es from the facial structures above. This trans-verse fracture across the entire lower maxillaseparates the alveolus as a mobile unit from therest of the midface. Fracture dislocations of seg-ments of the alveolus may be associated with thisfracture. With high-energy injuries, the palatemay be split in the midline in addition to theLeFort I fracture.

A pyramidal fracture of the maxilla is synony-mous with a LeFort II fracture. This fracture pat-tern begins laterally, similar to a LeFort I, butmedially diverges in a superior direction toinclude part of the medial orbit as well as thenose. The fracture extending across the nose maybe variable, involving only the nasal cartilage oras extensive as to separate the nasofrontal suture.