Evaluation of zygomatic trauma

CRANIOFACIAL

Evaluation and Treatment ofZygomatic Fractures

Patrick Kelley, M.D.Richard Hopper, M.D.

Joseph Gruss, M.D.

Austin, Texas; and Seattle, Wash.

Summary: Orbitozygomatic fractures are some of the most common facialfractures evaluated and treated by plastic surgeons. A considerable debateremains surrounding the manner of evaluation and appropriate treatmentmodalities. On the one hand, some would suggest that few fractures need formalopen reduction and internal fixation, whereas others would argue that the pullof the strong masseter muscle ultimately leads to inferior and lateral rotation ofthe zygoma, which justifies open reduction and internal fixation of most frac-tures excepting those fractures that are nondisplaced at all points of articulation.The authors hope to shed some light on these issues by conveying their per-spective on these fractures that has developed over several decades while ser-vicing a single, major Level I trauma center. In general, the authors feel thatthrough a detailed evaluation including an accurate physical examination of theface and orbit combined with detailed computed tomographic scanning of thecraniofacial skeleton and soft tissues, an appropriate treatment plan can begenerated. The common goal among all treatment plans should be the exactthree-dimensional restoration of the disturbed anatomy, that is, anatomicalreduction and the need for accurate restoration of orbital anatomy and volumewhen necessary. (Plast. Reconstr. Surg. 120 (Suppl. 2): 5S, 2007.)

Fractures involving the zygoma are among themost common facial fractures seen in traumacenters. Isolated fractures of the zygoma

have been variously termed zygomatic, tripod, ororbitozygomatic fractures. We recommend theterm orbitozygomatic fracture because this termrefers to the two most important considerations intreatment, which are accurate anatomical reduc-tion of the zygoma and restoration of appropriateorbital anatomy. Accurate anatomical reductionin the primary setting, usually within 2 weeks ofinjury, is imperative because this is the best op-portunity to restore the patient to their preinjurystate. Secondary correction of deformities related tothe untreated or mistreated, malpositioned zygomais challenging and often less successful because ofbony malunion and soft-tissue contracture.1–7

The diagnosis and management of orbitozy-gomatic injuries remains a controversial issueamong surgeons dealing with facial trauma. Thedebate continues unabated as to which of thesecommon fractures can be treated with less invasivemethods and which ones need more extensiveopen reduction and internal fixation to accom-plish the desired repair. The essential elements ofthe debate are centered on the degree of displace-ment and comminution that leads to secondarydeformities if left untreated or treated with lesscomprehensive techniques. Other issues lackingconsensus are the most reliable sites of assessmentof anatomical deformity and displacement, theappropriate sites of surgical exposure and stabili-zation, and the best methods of internal fixation.It is generally agreed, however, that the standardfor comparison of other techniques of repair ofthe orbitozygomatic structure is anatomical reduc-tion after full anatomical exposure (assessment of

From the Department of Craniofacial, Plastic, and Recon-structive Surgery, Dell Children’s Medical Center of CentralTexas; Division of Plastic Surgery, Department of Surgery,University of Washington; and Division of Craniofacial,Plastic, and Reconstructive Surgery, Children’s Hospitaland Regional Medical Center.Received for publication May 4, 2006; accepted December 6,2006.Copyright ©2007 by the American Society of Plastic Surgeons

DOI: 10.1097/01.prs.0000260720.73370.d7

Disclosure: None of the authors has any commer-cial associations or financial disclosures that mightcreate a conflict of interest with information pre-sented in this article.

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all articulations of the zygoma) and rigid fixationof all possible points of fixations (“buttresses”).Anything less than this is inherently a compromisethat may or may not be justified based on a logicalassessment of the degree of displacement, fracturepatterns, and comminution present.

ANATOMYThe zygomatic complex has been incorrectly

labeled in the past as a tripod and, in fact, shouldbe considered a quadripod. The lateral orbital wallshould be considered the base of the quadripod,with the four “legs” being the lateral orbital rim,the inferior orbital rim, the zygomaticomaxillarybuttress, and the zygomatic arch. Fractures of thezygomatic complex involve all four legs in additionto the fracture that extends through the lateralorbital wall. These four legs and the lateral orbitalwall make up five potential points of assessmentfor the degree of displacement. The legs of thequadripod provide two attachments to the cra-nium and two to the maxilla and create a largeportion of the orbital floors and lateral orbitalwalls. The zygomaticomaxillary complexes aretherefore surgically important in establishing or-bital volume and serving as a reference for reduc-tion of maxillary fractures to the cranium.

Fractures often, but not always, occur acrossthe three buttress-related sutures. The term tripodfracture was derived out of reference to the threerelated sutures, but reference to the associatedsutures is inconsequential because they do notprovide consistent and reliable information withregard to anatomical alignment, nor do they haveany significance with regard to durable points offixation. In addition, the term tripod fails to rec-ognize the posterior relationship of the zygomawith the sphenoid bone of the skull base and itsextension inferiorly down the lateral wall of themaxillary sinus.

The four legs represent two major buttressesof the face which are the upper transverse max-illary (across the zygomaticomaxillary and zygo-maticotemporal sutures) and the lateral verticalmaxillary (across the zygomaticomaxillary and thefrontozygomatic sutures). If the two buttresses ofthe zygoma are reduced and fixated, it is still pos-sible to have a rotational deformity of the zygomaabout the zygomaticosphenoid suture. The fourlegs are composed of narrow, dense bone, whichis excellent for alignment and fixation. However,because they are narrow structures, it is difficult todetermine the degree of rotation of the zygomafrom assessment of only one or two of these pointsalone. The four legs of the quadripod and the

lateral orbital wall in concert make up the fivemost accurate points of assessment for the degreeof displacement, and only by assessing at leastthree (more commonly all five) can accurate re-duction be ensured (Fig. 1).

The anterior portion of the lateral orbital wallis formed by the zygoma. The frontal bone andgreater wing of the sphenoid articulate with thezygoma through a suture within the lateral orbitalwall, which starts as the zygomaticofrontal sutureon the upper portion of the lateral orbital rim and

Fig. 1. (Above) Orbitozygomatic fractures can be described asquadripods, with the legs being the inferior orbital rim, the zy-gomaticomaxillary buttress, the lateral orbital rim, and the zygo-matic arch. The base of the quadripod is the lateral orbital wall.The most accurate means of determining anatomical reduction isthrough assessment of all five of these points in concert. (Below)The facial buttresses represent thickened regions of bone thatprovide structure to the face and stabilize the position of the facewith the cranium; as such, they represent ideal points of fixation.The illuminated skull illustrates that there is thickened bone atthe lateral orbital wall, the zygomatic arch, the inferior orbital rim,and the lateral wall of the maxillary sinus, known as the zygomat-icomaxillary buttress.

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has a slight posteroinferior course within the orbitto the anterior to mid portion of the inferior or-bital fissure. The lateral orbital wall is the thickestportion of the orbit and is rarely comminuted.This portion of the orbit has a distinct shape andis the longest interaction of the zygoma with therest of the facial bones with attributes in all threedimensions. This makes the zygomaticosphenoidfracture line the single most reliable indicator ofdegree and direction of displacement and of an-atomical alignment of the zygoma in all three di-mensions (Fig. 2).

The zygomatic arch serves as the origin of themasseter on its inferior margin and the attach-ment of the fascial layers of the face (superficialmusculoaponeurotic system) and the temporal re-gion (temporoparietal fascia) superficially. Theorigin of the masseter is the major deformingforce acting on the fractured zygoma, interferingwith mobilization and reduction and contributingto relapse in the inadequately fixated fracture. Anoblique suture in the mid portion of the archrepresents the articulation of the contribution ofthe zygoma and the contribution of the temporalbone to the arch proper. The temporomandibularjoint abuts the posteromedial aspect of the arch,with its anterior limit at the articular tubercle ofthe zygomatic arch. The term arch is a misnomer,because it is linear through most of its course (Fig.3, above). It is gently curved in its posterior aspectnear the region of the articular tubercle of the

Fig. 2. (Left) The zygomatic complex articulates with the frontal bone and sphenoid through a suture within the lateral orbital wall.Orbitozygomatic fractures often but not always extend directly through this suture line (arrows). The thickness of the lateral orbitalwall in relation to the other orbital walls often prevents comminution at this fracture site. The lack of comminution in addition to thenatural three-dimensional character of this concave wall makes it the single most reliable indicator of anatomical reduction. (Right)One exception to this rule is the presence of an orbitozygomatic injury ipsilateral to an impacted sphenoid fracture, unless it is a largefragment that can be anatomically reduced before reduction of the orbitozygomatic injury.

Fig. 3. (Above) The term zygomatic arch is a misnomer. As seenin this inferior view of the skull, the arch is straight through mostof its course, with curvatures posteriorly and anteriorly. (Below)Malreduction and fixation of the zygomatic “arch” as an archleads to disturbances in facial width and cheek projection.

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temporomandibular joint. It then maintains a lin-ear projection with a slight medial angulation un-til it sharply curves at its most anterior aspect tomeet the maxilla. The zygomaticomaxillary sutureline lies at approximately the mid portion of thisanterior curvature; thus, both the zygoma andmaxilla contribute to the anterior curvature. Theanatomy of the arch is critical because it is the archthat forms the outer facial frame, determining thewidth and the anterior projection of the midface.Without proper restoration of the position of thearch, facial width and midface projection will beincorrect (Fig. 3, below).

DIAGNOSIS

Displacement of the zygoma leads to cheek de-pression and, depending on the condition of thearch, disturbance of facial width. Physical signs andsymptoms of zygoma fractures include (1) subcon-junctival hemorrhage and periorbital ecchymosis;(2) disturbance of sensation in the region of infraor-bital nerve; (3) palpable step-offs in the upper lateralorbital rim, inferior orbital rim, and upper buccalsulcus; (4) emphysema within the orbit or overlyingsoft tissues of the cheek; (5) trismus; and (6) mal-position of the globe and/or diplopia.

Fig. 4. Most orbitozygomatic injuries present with ipsilateral proptosis secondary to orbital swelling even in cases of orbital blow-out(orbital expansion). When a patient presents with acute enophthalmos, it is indicative of severe orbital expansion, as indicated in theassociated floor fracture of this patient with an otherwise simple orbitozygomatic fracture.


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Facial swelling is usually substantial by the timethe patient presents to the plastic surgeon, and ittends to minimize the degree of deformity bymasking globe and cheek malposition. The swell-ing has usually resolved sufficiently by approxi-mately 2 weeks after injury that the underlyingdeformity can be appreciated. It is important forthe patient to understand this dynamic becausetreatment should be carried out within the first 2weeks after injury, still within the timeframe whereit is difficult for the patient to appreciate the truedeformity.

The position of the globe is affected by theintegrity of the periorbital fascial support, the di-rection and degree of displacement of the zygoma,and the degree of concomitant swelling. Fracturesthat cause an increase in orbital volume (blow-outfracture) will predispose to enophthalmos, butduring the acute period, swelling within the orbitmay cause some degree of proptosis despite theexpansion of the orbit. As swelling resolves, theglobe progressively sinks back, revealing the un-derlying orbital expansion. Zygomatic fracturesthat present with acute enophthalmos indicate se-vere displacement and orbital expansion (Fig. 4).Zygomatic fractures that impinge into the domainof the orbit (“blow-in” fracture) reduce the orbitalvolume and present with acute proptosis, whichwill improve only slightly as swelling resolves.

Some degree of trismus is common with zy-gomatic fractures secondary to direct injury to themasseter and its origin on the zygomatic arch.When the arch is severely collapsed or impacted,it can cause a trismus secondary to mechanicalimpedance of the coronoid process as it slidesupward, preventing closure of the mouth, but thisis less common than trismus secondary to directmuscle injury.

Secondary deformities related to untreated ormistreated fractures of the zygoma are not un-common. These deformities are especially com-mon in the patient with associated panfacial in-juries. The patient with a malpositioned zygomatypically presents with an underprojected cheekand a wide face, but overprojection is also possible.Failure to evaluate and treat the concomitant or-bital deformity usually results in globe malpositionif the fascial support of the eyeball has been dis-rupted. Enophthalmos is the usual result, but oc-casionally exophthalmos can occur if the orbitalvolume is decreased by a blow-in type fracture.Secondary deformities can also result from iatro-genic malposition of the overlying soft tissues.Even with accurate reduction of the bone anat-omy, soft-tissue deformities can result from inad-

equate suspension after extensive surgical expo-sure. Cheek ptosis, inferior displacement of thelateral canthus, temporal hollowing, and lower lidectropion are among the most common findings.

IMAGINGAdvancement of computed tomographic

scanning technology has resulted in vast im-provements in the quality of images, the abilityto develop three-dimensional models (digitaland stereolithographic), increased speed of scan-ning, and reduced radiation exposure. This hasestablished computed tomography as the modalityof choice for the evaluation of facial fractures.

Patients with suspected facial trauma on initialevaluation are evaluated with a complete cranio-facial computed tomographic scan. Our protocolincludes a full facial analysis from the top of the headthrough the mandible with 1.5-mm axial cuts. Coro-nal reformatting can then be constructed fromthis data set without additional scanning. Al-though sagittal reformat and three-dimensionalrepresentation of the data are not part of our usualprotocol, they each have their role in specific sit-uations. Sagittal reformat is particularly useful inassessing the effect of a complex orbital fractureon the inferomedial bulge of the orbital floor. Ina busy Level I trauma center, where many patientspresent with neurologic compromise (head injuryor intoxication) and cannot comply with a com-plete physical examination, it is prudent to obtaina complete scan at the time that the head com-puted tomographic scan is obtained; doing sotakes only a few seconds.

PRINCIPLES OF SURGICAL PLANNINGAND REPAIR

The zygoma has five articulations that can beused to guide anatomical reduction: (1) the lateralorbital rim, (2) the inferior orbital rim, (3) thezygomaticomaxillary buttress, (4) the zygomaticarch, and (5) the lateral orbital wall. Rigid internalfixation can be achieved at four of these articula-tions through limited access incisions. Fixation offractures through the lateral orbital wall requiresextensive exposure by means of a coronal incision,with elevation of the temporalis muscle out of thesphenopalatine fossa. This exposure is reservedfor rare cases with severe comminution and dis-placement of the zygomatic arch and lateral or-bital wall. In theory, reduction and fixation ofthree of the four potential points of fixation (but-tresses) will correct both translation and rotationof the zygoma in three-dimensional space. Whenone or more of the buttresses is comminuted,


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exposure and reduction of all four buttresses be-comes increasingly important. The use of estab-lished craniofacial techniques to achieve wide ex-posure and mobilization of the entire zygoma is ofparamount importance to accurate anatomical re-duction of the severely displaced and comminutedzygoma.

With a careful assessment of a fine-cut com-puted tomographic scan of the facial skeleton,examining both the axial and coronal cuts, thesurgeon should be able to accurately diagnose theexact fracture pattern and search for any degreeof separation or comminution at the multiple frac-ture sites. All five points of assessment listed aboveshould be evaluated carefully on the computedtomographic scan for the degree of displacementand comminution. Simple elevation of the frac-ture by means of a Gillies or intraoral approach isusually reserved for minimal displacement at allfives buttresses with no comminution. In thesecases, the periosteal hinge is still present at themajority of the fracture sites, and the zygomashould be stable in reduction. If there is a signif-icant degree of displacement at any of the fivesites, particularly if there is associated comminu-tion, the pull of the masseter muscle will cause acollapse at the area of comminution, particularlyif it is at the zygomaticomaxillary buttress. Ourpreferred method for mobilizing the displacedzygoma, whether it requires extensive exposure orlimited exposure, is to place a mayo scissors pos-terior to the body of the zygoma by means of theupper buccal sulcus incision. This affords an ex-cellent purchase on the body of the zygoma andmobilization is usually associated with an audibleclunk. A Carroll-Jerrard screw can be used toachieve the same effect.

If significant displacement or comminution ispresent at any of the five sites, an open reductionand internal fixation is indicated. The surgeonthen decides how many of the five points of frac-turing need to be exposed and assessed intraop-eratively. The condition of the zygomatic arch is akey element in the decision tree as to which inci-sions are required. The arch establishes the outerfacial frame (facial width and midface projection).A careful analysis of patients who present withsecondary midface depression and increased fa-cial width reveals that all had untreated deformityof the zygomatic arch. Segmentation, lateral dis-placement, telescoping, and comminution of thearch are indications for exposure, reduction, andfixation (Fig. 5).

The safest approach to the zygomatic arch is bymeans of a coronal incision with protection of the

frontal branch. If the zygomatic arch has a green-stick fracture with minimal displacement or is me-dially displaced, it is not necessary to expose thezygomatic arch, and the entire open reduction canbe performed from an anterior approach withoutthe need for a coronal incision (Fig. 6). An ante-rior approach in our center involves three inci-sions, including an upper buccal sulcus, a mid-eyelid (subtarsal) or transconjunctival, and thelateral part of an upper blepharoplasty incision.

The zygomaticosphenoid alignment at the lat-eral orbital wall is recognized as a fundamental keyto the proper reduction of orbitozygomatic inju-ries. Displacement at this surface indicates a re-sidual rotational deformity. As mentioned earlier,the thick lateral orbital wall is rarely comminuted.Accurate reduction of the lateral orbital wall incombination with inspection of the other three orfour sites as necessary will allow the surgeon toachieve a very accurate reduction of the fracturebefore the application of rigid fixation. Subperi-osteal dissection at the exposed buttresses is lim-ited to the minimum required to assess reductionand achieve fixation but always adequate to allowfull assessment of the fracture character.

The pull of the masseter can often frustrateadequate mobilization of the fracture fragment.This can be overcome by either chemical paralysisor partial or complete release of the anterior por-tion of the masseter from the zygoma by means ofthe intraoral or coronal incision. The correct re-duction is best accomplished by placing a tempo-rary interosseous wire at the frontozygomatic su-ture on the lateral orbital rim to set the verticalheight of the zygoma, followed by rotation of theentire complex into correct position. Failure toaccurately reduce the fractures will result in thezygomatic complex being stabilized in an unre-duced position otherwise known as an open in-ternal fixation without reduction.

Rigid fixation with plates and screws is theaccepted standard of fixation of reduced fracturesof the zygoma. There is no consensus, however, onthe strength of plates required at each fracture sitethat will provide sufficient rigidity to resist theregional deforming forces (Fig. 7). All currentlyavailable internal fixation systems have a large se-lection of plates of various thicknesses, sizes, andstrengths. The benefit of a smaller plate is lessdissection required to place it and potentially lesspalpability. These benefits must always be weighedagainst the fundamental goal of rigid fixation toretain reduction and promote osseous union.Thus, it is always safer to err on a slightly larger andstronger plate than a smaller plate that will not be


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strong enough to withstand the forces acting atthat specific fracture site. The best site for rigidfixation is the zygomaticomaxillary buttress, be-cause this is the direct antagonist to the pull of themasseter muscle. In addition, this site of fixationis deep, and plates are rarely felt in this area. Thus,a longer and stronger fixation plate (2.0 mm)should usually be used at this site. Likewise, it isvery important to primarily bone graft any sites ofbone loss, especially the zygomaticomaxillary but-tress, because of its antagonistic effect on the pull

of the masseter. The infraorbital rim is an impor-tant site for fracture reduction but is the leastimportant site for fracture fixation, and either aninterosseous wire or a small plate can be used inthis site quite safely.

The frontozygomatic suture line representsvery thick bone that is ideal for rigid fixation.Unfortunately, plates in this area are readily pal-pable, and therefore it is usually advisable to usesmaller plates at this location, provided that thefracture is not too unstable. It is very important to

Fig. 5. Segmentation, lateral displacement, telescoping, and comminution of the arch are indications for exposure, reduction, andfixation.


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realize that the frontozygomatic suture line is theleast important site with which to determine thedegree of rotation of the fracture, because manysignificantly displaced fractures will have very littleseparation at the frontozygomatic suture line.Thus, it is essential to look at the frontozygomaticsuture line in combination with exposure at theother sites to assess the correct degree of reduc-tion of the fracture. The zygomatic arch, if nec-essary, is a very important site of fixation, andstronger plates usually should be used in this area.It is very important not to stabilize and reconstructthe arch as a true arch but to ensure that thecentral portion is flattened and compressed me-dially to ensure restoration of facial width andcorrect projection of the zygomatic body. A fre-quently missed zygomaticomaxillary complex frac-ture is at the temporal bone portion of the uppertransverse maxillary buttress. When the arch is

Fig. 7. Plating guidelines for fixation of orbitozygomatic frac-tures. A 2.0-mm plate is indicated at the zygomaticomaxillarybuttress because this strong buttress directly opposes the de-forming forces of the masseter muscle. A 2.0-mm plate is easilyconcealed in the region of the arch and provides further stabilityto this structure. Plates placed on the lateral orbital rim and theinferior orbital rim tend to be more palpable; therefore, smallerplates or wires can be used in these regions because these areasbear less weight. A 1.7- or 2.0-mm plate is recommended on theinferior orbital rim in the presence of an ipsilateral naso-orbito-ethmoid fracture to further stabilize the adjacent fractures in thecorrect position.

Fig. 6. If the zygomatic arch has a greenstick fracture with min-imal displacement or is medially displaced, it is not necessary toexpose the zygomatic arch, and the entire open reduction can beperformed from an anterior approach without the need for acoronal incision.


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fractured posteriorly from the zygomatic processof the temporal bone, care must be taken not toplace screws into the adjacent glenoid fossa andmandibular condyle (Fig. 8).

Once the entire orbitozygomatic complex hasbeen reduced and rigidly fixed in its correct align-ment, the orbit then needs to be carefully evaluatedfor possible bony loss and needs to be anatomicallyreconstructed to accurately restore the correct or-bital volume. We generally use a thin sheet of Med-por (Porex Surgical, Inc., Newnan, Ga.) to recon-struct simple disruptions of a single orbital wall.More extensive fractures of the orbit involving largebone loss or multiple walls are more commonly re-constructed with cranial bone graft harvested fromthe outer cranial cortex. Achieving the correct or-bital volume in complex fractures is more challeng-ing and is more commonly associated with the needfor secondary procedures to fine tune the positionof the globe. Secondary surgery in a primarily bonegrafted orbit is much easier to perform because aperfect dissection plane develops between the bonegraft and periorbita.

Finally, the midfacial soft tissue needs to berepositioned in relation to the bony reconstruc-tion and skeleton framework by the insertion ofmultiple drill holes in the inferior and lateral or-bital rims to enable suspension of the muscularperiosteal envelope to these drill holes. We use atleast four 2-0 resorbable sutures that attach toindependent drill holes starting in the region ofthe mid inferior orbital rim and extending to thelower lateral orbital rim below the lateral canthalattachment. The lateral canthal tendon is reat-

tached in a slightly overcorrected position when ithas been detached in the dissection.

APPROACH TO THE ARCHSafe exposure of the entire zygomatic arch

and assessment of its exact relationship to theremaining craniofacial skeleton can be accom-plished only through an extended coronal in-cision. The scalp flap must be dissected metic-ulously to prevent postoperative morbidityrelating to the following:

1. Weakness or permanent paralysis of thefrontal branch of the facial nerve

2. Temporal depression related to atrophy ofthe temporal fat pad

3. Displacement of the lateral canthal ligamentresulting in an antimongoloid slant of thepalpebral fissure

4. Inferior descent of the lateral cheek tissuessecondary to failure to reconstruct the inci-sion in the temporal fat pad

5. Preauricular scar and injury to the superfi-cial temporal vessels

Our approach to the zygomatic arch basedprimarily on the location of the frontal branch ofthe facial nerve (deep to the superficial muscu-loaponeurotic system, below the arch; superficialto the temporoparietal fascial, above the arch) hasbeen previously described. It is based on dissectionone plane deeper than the nerve, entering thesubperiosteal plane 2 cm above the orbital rimsand entering the plane deep to the superficiallayer of the deep temporal fascia 1 cm above the

Fig. 8. Accurate reduction and fixation of the base of the zygomatic arch is important for reestablishing the correct facial width andprojection. Care must be taken when fixating fractures at the base of the zygomatic arch to avoid penetration of screws into theglenoid fossa. Correct position of hardware is demonstrated in this coronal image.


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zygomatic arch. Damage to the temporal fat padcan be avoided by approaching the arch above thefat pad, just deep to the first fascial layer of thethick deep temporal fascia. We almost never re-quire a preauricular extension of the incision togain additional exposure. Equally adequate expo-sure can be achieved by extending the incisionposterior to the ear and raising the soft tissuessubperiosteally to the level of the external auditorycanal.

Full exposure of the arch requires division anddissection of many important suspensory liga-ments in the region. It is imperative to reestablishthe integrity of these structures to prevent thepremature descent of these structures. Specifi-cally, the lateral canthal tendon must be takendown to gain exposure of the arch. The appro-priate repositioning of this tendon to the internalsurface of the lateral orbital wall is necessary toprevent postsurgical deformity. Resuspension ofthe deep temporal fascia at the point of divisionjust above the zygomatic arch reestablishes the softtissues over the reconstructed arch to prevent thearch from becoming displaced into the subcuta-neous plane. Care must be taken when placingthese sutures to prevent inadvertent damage tothe frontal branch of the facial nerve. In addition,extension of the incision behind the ear mobilizesthe superior aspect of the ear and requires resus-pension to prevent malpositioning of the ear andcollapse of the external auditory canal.

ZYGOMATIC FRACTURES ASSOCIATEDWITH IPSILATERAL

NASOETHMOIDAL FRACTURESOne of the important sites of zygomatic re-

duction is the inferior orbital rim. Because this siteis so readily visible through direct exposure, thereis a tendency for surgeons to rely heavily on thissite. One of the pitfalls of the inferior orbital rimis that it is often displaced by the presence of anipsilateral naso-orbito-ethmoid fracture. When re-viewing our results and results of patients referredto our center for secondary correction of dis-placed zygomatic fractures, there is often a missedipsilateral naso-orbito-ethmoid fracture.

The naso-orbito-ethmoid fracture involves frac-tures through the nasofrontal junction, medial or-bital wall (ethmoids), frontal process of the maxillaat the pyriform (medial nasomaxillary buttress), andthe inferior orbital rim. Although severe naso-or-bito-ethmoid fractures associated with comminu-tion and displacement are fairly easy to diagnoseby the presence of telecanthus and nasal distor-tion, less comminuted and displaced fractures can

be much more subtle and easily missed. The na-sofrontal junction in these less severe naso-orbito-ethmoid injuries is often greensticked, with pos-terior, inferior displacement of the medialbuttress and inferior orbital rim (Fig. 9).

If an ipsilateral naso-orbito-ethmoid is not ap-preciated, reduction of the zygoma to the malpo-sitioned medial portion of the inferior orbital rimwill lead to fixation of the zygoma in an incorrectposition. The clinical consequence to using thisdisplaced anatomy as a guide to reduction of theorbitozygomatic complex is usually malar flatten-ing, hemifacial widening caused by lateral dis-placement of the zygomatic arch, enophthalmos,ocular dystopia, a depressed inferior orbital rim,and telecanthus.

The best way to evaluate for the presence of anipsilateral naso-orbito-ethmoid in the absence ofovert clinical signs is through careful evaluation ofa fine cut, craniofacial computed tomographicscan. Findings consistent with naso-orbito-eth-moid injury on axial views include lateral, inferior,and posterior displacement of the nasomaxillarybuttress (often seen as a discrepancy in the posi-tion of nasolacrimal ducts), opacification andcomminution of the ethmoids air cells, ipsilateraldepression and displacement of the nasal bone,displaced fractures of the medial orbital wall, andsignificant periorbital emphysema. Coronal viewsmay demonstrate medial and inferior displace-ment of the nasomaxillary buttress or fracture ofthe inferior orbital rim with posterior displacement.

Fig. 9. The presence of an ipsilateral naso-orbito-ethmoidfracture can be misleading as to the correct position of thezygoma. Failure to appreciate an ipsilateral naso-orbito-eth-moid will lead to malreduction of the fracture and postoper-ative deformities related to malposition of the zygoma and thenaso-orbito-ethmoid.


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Although the inferomedial orbit is often involved inorbitozygomatic fractures, the medial orbital wall isnot a component of pure orbitozygomatic injuries.Fractures involving the medial orbit should alert theexaminer to the possible presence of an ipsilateralnaso-orbito-ethmoid fracture.

The displaced naso-orbito-ethmoid should beaddressed before final reduction of the zygoma. Ifthe fracture at the nasofrontal junction is a green-stick fracture, no additional fixation of this site isrequired because the nasomaxillary buttress canbe used as a guide to assist with proper positioningof the naso-orbito-ethmoid fragment. A strongplate on the nasomaxillary buttress will stabilizethe naso-orbito-ethmoid segment once it is cor-rectly reduced. The plate on the inferior orbitalrim will further stabilize the naso-orbito-ethmoidsegment in proper reduction because there areminimal muscular deforming forces acting on thenaso-orbito-ethmoid complex. However, if thenaso-orbito-ethmoid component is displaced andunstable at the nasofrontal suture, additional fix-ation at this site will be required, usually througha coronal incision.

It is extremely important to preserve the at-tachment of the medial canthal ligament to thelacrimal bone during dissection. The medial can-thus is rarely avulsed from its bony attachment atthe time of the actual injury; rather, it is usuallystripped from its insertion during exposure of thefracture. Preservation of its insertion to the bonyfragments facilitates proper positioning of the me-dial canthus, preventing traumatic telecanthus.

DISCUSSIONPoorly treated orbitozygomatic injury is un-

doubtedly the most common posttraumatic prob-lem seen by most craniofacial surgeons today. Theadvent of rigid fixation using plates and screws hasgiven many surgeons a false sense of security in themanagement of these fractures. The use of platesand screws is probably the least important part ofthe entire treatment protocol in these patients. Allthe plates and screws represent are the most so-phisticated and best form of fixation of the frac-tures after they have been reduced. The most im-portant aspect of the treatment of these fractures,and all other facial fractures, is the careful expo-

sure of all fractures and the accurate reduction ofthese fractures in a three-dimensional fashion. Fa-cial symmetry is achieved by restoring the three-dimensional position of the malar prominence,and orbital volume is restored by alignment of thezygoma with the sphenoid. If this is not done, thefractures will merely be rigidly plated in an unre-duced position. All craniofacial surgeons todaydealing with a significant volume of facial fractureshave noticed that there is a rapidly increasing ep-idemic of patients seen with fractures plated rig-idly in the wrong position. The complications weare now seeing with fractures plated in the unre-duced position are much more disastrous for thepatient than those that used to be seen with simpleelevation or when fixation using interosseus wireswas used. It is essential for the surgeon treatingthese very common injuries to thoroughly under-stand that there is no substitute for accurate ex-posure and reduction of the fractures. Only oncethis is done will rigid fixation with plates andscrews accomplish its planned objective.

Joseph Gruss, M.D.Children’s Hospital CH-784800 Sandpoint Way N.E.

Mail Stop G-0035Seattle, Wash. 98115

[email protected]

REFERENCES1. Gruss, J. S., Van Wyck, L., Phillips, J. H., and Antonyshyn, O.

The importance of the zygomatic arch in complex midfacialfracture repair and correction of posttraumatic orbitozygo-matic deformities. Plast. Reconstr. Surg. 85: 878, 1990.

2. Gruss, J. S., Antonyshyn, O., and Phillips, J. H. Early definitivebone and soft-tissue reconstruction of major gunshot woundsof the face. Plast. Reconstr. Surg. 87: 436, 1991.

3. Gruss, J. S. Advances in craniofacial fracture repair. Scand. J.Plast. Reconstr. Surg. Hand. Surg. Suppl. 27: 67, 1995.

4. Gruss, J. S., Whelan, M. F., Rand, R. P., and Ellenbogen, R. G.Lessons learnt from the management of 1500 complex facialfractures. Ann. Acad. Med. Singapore 28: 677, 1999.

5. O’Hara, D. E., DelVecchio, D. A., Bartlett, S. P., and Whitaker,L. A. The role of microfixation in malar fractures: A quanti-tative biophysical study. Plast. Reconstr. Surg. 97: 345, 1996.

6. Phillips, J. H., Gruss, J. S., Wells, M. D., and Chollet, A. Peri-osteal suspension of the lower eyelid and cheek followingsubciliary exposure of facial fractures. Plast. Reconstr. Surg. 88:145, 1991.

7. Yaremchuk, M. J., Gruss, J. S., and Manson, P. N. (Eds.). RigidFixation of the Craniomaxillofacial Skeleton. Stoneham, Mass.:Butterworth-Heinemann, 1992.


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Evaluation of zygomatic trauma

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