Key points
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The maxilla, palate, zygomaticomaxillary complex, nasal bones, orbits, nasal-orbital-ethmoid complex, and frontal sinus may be affected by midface trauma.
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Forces directed onto the midfacial skeleton are absorbed and transmitted through vertical and horizontal buttresses.
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By reconstructing and stabilizing the vertical and horizontal buttresses of the midface, occlusal forces can be tolerated and facial height, width, and projection can be restored.
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Complications of midface trauma include bleeding, malunion/nonunion, neurologic complications, ocular complications, and complications involving the lacrimal system.
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Frontal sinus fractures can be followed with close observation or treated surgically with anterior table reconstruction alone or in combination with sinus obliteration or cranialization.
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The decision to treat a frontal sinus fracture is dependent on the amount of bony displacement, the involvement of the posterior table and intracranial contents, and the condition of the nasofrontal outflow tract.
Introduction
The management and surgical treatment of midface maxillofacial trauma can present one of the most challenging undertakings for the maxillofacial surgeon. The midfacial skeleton and its soft tissue attachments protect the brain and eyes from injury and are closely related to the senses of vision and smell. Speech, mastication, and facial appearance can all be affected by midfacial trauma. Accurate correction of the bony skeleton to the preinjury state is vital to the restoration of function and esthetics.
Introduction
The management and surgical treatment of midface maxillofacial trauma can present one of the most challenging undertakings for the maxillofacial surgeon. The midfacial skeleton and its soft tissue attachments protect the brain and eyes from injury and are closely related to the senses of vision and smell. Speech, mastication, and facial appearance can all be affected by midfacial trauma. Accurate correction of the bony skeleton to the preinjury state is vital to the restoration of function and esthetics.
Initial assessment
The initial evaluation and management of midface trauma should be directed at stabilization of the patient. Motor vehicle collisions represent the most common cause of facial trauma. Other causes include assaults, falls, sporting injuries, and home and occupational accidents. The high-energy nature of these injuries often leads to multisystem involvement and, therefore, a thorough, systematic evaluation of the entire patient should precede the management of their facial injury. The most common concomitant injuries in patients with panfacial fractures include intracranial injury or hemorrhage, abdominal organ injury, pneumothorax, pulmonary contusion, spine fracture, rib or sternum fracture, extremity fracture, and pelvic fracture. Trauma centers are especially equipped to deal with the evaluation and management of these injuries. Specially designed teams directed by trauma surgeons and emergency room physicians lead the initial management of these patients. Oral and maxillofacial surgeons are most commonly consulted after the initial evaluation and management of the most life-threatening injuries.
Of particular concern in patients with midface trauma are:
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The cervical spine
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The airway
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Hemorrhage
Midface fractures are positive predictors of cervical spine fractures and dislocations. The cervical spine should be immobilized until cervical fractures have been ruled out by imaging or clinical examination. If an injury is identified, head and neck immobilization and positioning during the repair of the midface injury should be coordinated with the spinal surgeon.
Airway obstruction can lead to asphyxia and death after midfacial trauma. Bleeding, fractured teeth, oral secretions, vomitus, foreign bodies, and edema can affect airway patency. If the airway obstruction cannot be cleared or controlled, a definitive airway should be placed via endotracheal intubation or cricothyrotomy. Oral endotracheal intubation is successful in the hands of experienced emergency physicians using rapid sequence induction. In terms of midface facture repair, nasal intubation allows for the simplest establishment of the dental occlusion. However, the increased difficulty, decreased speed and possibility of a concomitant basilar skull injury with concern for cranial intubation deter most providers from attempting this in an emergency setting. If needed, nasal intubation is better performed as a non-emergent procedure in the operating room prior to fracture repair. When attempts at oral intubation are unsuccessful, a surgical airway via cricothyrotomy provides the fastest approach. Cricothyrotomy should then be converted to a tracheostomy, if necessary, in a controlled environment with less risk of losing airway control.
With a secure airway, uncontrolled bleeding can be addressed. The midface has a robust blood supply, with contributions from both the internal and other branches of the external carotid arteries. The sphenopalatine and other branches of the internal maxillary artery can be significantly damaged during midfacial trauma. Although rare, life-threatening hemorrhage can result. When severe epistaxis is encountered, direct pressure via anterior and posterior nasal packs can be used. Often, posterior bleeding is encountered with drainage into the nasopharynx. A 10-French Foley catheter can be inserted through each nare, inflated with sterile water, and then pulled anteriorly. This procedure tamponades off the posterior chamber and in combination with an anterior packing provides a simple way of nasal packing. Anterior nasal packs can be accomplished with the layering of ribbon gauze or with the use of expandable sponges such as Merocel (Medtronic, Inc, Mystic, CT, USA) or Rhino Rocket (Shippert Medical Technologies Corporation, Centennial, CO, USA). Bleeding from intraoral wounds can be controlled with gauze packing, suturing, or electrocautery. If the hemorrhage has caused significant volume loss, fluid should be replaced with lactated Ringer solution or normal saline to restore blood pressure until blood can be typed and crossmatched. Alternatively, the patient can be transfused with O-negative blood. Once the primary advanced trauma life support survey has been completed and the patient’s airway and cardiopulmonary status have been stabilized, the secondary survey, including a more detailed facial examination, can be accomplished.
Clinical examination
The awake patient can be questioned about their occlusion, sensory changes, and pain. The patient’s subjective assessment of their bite can be one of the most sensitive measures when evaluating for the presence of a maxillary or mandibular fracture. Edema within the temporomandibular joint may also cause changes in occlusion and should be taken into consideration. Paresthesia and numbness of the upper lip, side of the nose, and maxillary gingiva suggest a fracture involving the infraorbital nerve and are common with maxillary and orbital fractures. Pain is also a common finding in the region of a fracture.
The physical examination is best accomplished when performed systematically. We prefer a top-down/outside-in approach. The soft tissue is first inspected for lacerations, edema, and ecchymosis. Abnormalities and asymmetries in midfacial height, width, and projection are assessed. The intercanthal distance is measured, and epiphora and rhinorrhea are noted if present. A cranial nerve examination is performed, including a detailed assessment of visual acuity and extraocular movements. Bimanual palpation can then be undertaken to assess for bony steps, mobility, crepitus, and tenderness. Palpation begins with the frontal bones and supraorbital rims. It then extends to the lateral orbits, zygomatic arches, and zygomas. The infraorbital rims are next addressed, followed by the medial orbits and nasal bones. The maxilla is then palpated. In addition to palpation, the maxilla can be grasped around the anterior maxillary teeth, with the thumb inferior to the anterior nasal spine and the forefinger at the depth of the palatal vault to assess for mobility. An intraoral examination is accomplished. The intraoral soft tissues are inspected for lacerations and ecchymosis. The teeth should be examined for fractures, luxations, and avulsions. The alveolar bone is assessed for displacement and mobility. Maximum incisal opening, lateral excusive movements, and protrusive movements are recorded and the occlusion is assessed.
A radiographic examination should always accompany the clinical examination in the patient with facial trauma. Although plain films can be useful for identification of specific fracture elements, computed tomography (CT) has become the standard for evaluating midfacial injuries. CT scans provide information in 3 planes of space (axial, coronal, and sagittal), and can be used as a standalone radiographic modality. The CT data can also be reconstructed into a three-dimensional (3D) image, increasing its usefulness. At a minimum, we prefer to order a non-contrast maxillofacial CT with 1-mm to 2-mm axial slices and coronal, sagittal, and 3D reconstructions ( Fig. 1 ).
Maxillary and LeFort fractures
Anatomy
The maxilla, palate, nasal bones, and zygomas comprise most of the midfacial skeleton. The ethmoids, greater wing of the sphenoid, and frontal bone comprise elements of the bony orbit and connect the anterior facial skeleton to the cranial base. Forces directed onto the midfacial skeleton are absorbed and transmitted through vertical and horizontal buttresses. These buttresses constitute areas of dense, thick bone that support the maxilla and are more resistant to deformation when forces are applied. They are not only important in protecting the vital structures of the midface but they are also essential landmarks used during reconstruction. The buttresses provide higher-quality bone for internal fixation and guide reconstruction of facial height, width, and projection.
The midface is more resistant to vertical forces than horizontal and shear forces. This resistance is because of the strength of the 4 vertical buttresses ( Fig. 2 ):
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Nasomaxillary (medial)
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Zygomaticomaxillary (lateral)
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Pterygomaxillary (posterior)
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Ethmoid-vomerian or septal (midline)
The paired nasomaxillary buttresses extend from the frontal bone to the nasal bones and medial orbit, and along the pyriform apertures and end at the maxillary alveolus in the region of the maxillary canines. Laterally, the pterygomaxillary buttresses extend from the frontal bone, down the lateral orbital rims to the zygoma and end at the maxillary alveolus in the region of the maxillary second molars. The pterygomaxillary buttresses provide posterolateral support and extend from the pterygoid plates of the sphenoid bone to the posterior maxilla. The midline ethmoid-vomerian or septal strut joins the frontal bone and cranial base with the midpalatal suture.
Although the horizontal buttresses have less impact on force dissipation, they are important for the restoration of facial width. The horizontal buttresses include ( Fig. 3 ):
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Superior orbital rims (superior)
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Inferior orbital rims/zygomatic arch (central)
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Maxillary alveolus (inferior)
Superiorly, the frontal bone extends from 1 superior orbital rim to the other, bridged by the bone at the nasofrontal region. The central aspect of the midface is composed of a horizontal buttress extending from 1 zygomatic arch and inferior orbital rim, across the midline and pyriform aperture, to the contralateral counterpart. The most inferior horizontal midface buttress is the maxillary alveolus.
Classification
The work of René LeFort has stood the test of time in the classification of maxillary and midfacial bony trauma. LeFort was a French army surgeon who conducted a series of experiments in Lille, France at the turn of the twentieth century. He published his work, “Etude expérimentale sur les fractures de la machoire supérieure” in 1901. LeFort took whole human cadavers and severed heads and inflicted traumatic forces on the midface with variations in force and vector. He then boiled the heads to help remove the skin and examined the skulls. LeFort found that most fractures occurred along 3 “great lines of weakness,” which are now referred to as LeFort I, II, and III fractures.
A LeFort I fracture, or Guerin fracture, is a transverse fracture that occurs along the maxilla ( Fig. 4 A). These fractures typically result from a force directed above the level of the teeth. They extend from the pyriform rims, through the anterior, lateral, and posterior walls of the maxillary sinus, and through the pterygoid plates of the sphenoid bone. The nasal septum is often fractured. Because of the pull of the medial and lateral pterygoid muscles, these fractures often result in a posterior and inferior positioning of the posterior maxilla, resulting in an anterior open bite.
A LeFort II fracture is a pyramidal fracture that extends from the maxillary tuberosity through the medial aspect of the inferior orbital rim in the region of the zygomaticomaxillary suture, through the lacrimal bone, and up to the nasofrontal suture (see Fig. 4 B). Again, the nasal septum is often fractured, and the nasal bones may be displaced. A force directed at the nasal bones is responsible for this fracture pattern.
A LeFort III fracture includes the zygomas and a portion of the lateral and inferior orbit (see Fig. 4 C). These fractures are caused by forces directed at the level of the orbits. They extend through the zygomaticofrontal and zygomaticotemporal sutures, course along the lateral orbit, through the inferior orbital fissure and medial orbit to the nasofrontal suture. Posteriorly, they end at the pterygomaxillary junction. LeFort III fractures represent a true craniofacial disjunction, that is, the separation of the midfacial skeleton from the cranial base.
Although useful in organizing and communicating the nature of bony injuries, the LeFort classification scheme does not always represent the fracture pattern seen in patients. Fractures are dependent on the position, vector, and intensity of the force directed at the bony skeleton. They are rarely completely symmetric bilaterally and often occur unilaterally. Fractures may also involve the palate, which is discussed later. It may be more accurate to describe and identify the specific fracture elements present when planning and treating midface fractures.
Diagnosis and treatment planning
The general approach to the management of midface trauma was discussed earlier. Maxillary and LeFort fractures may present with a variety of clinical findings ( Fig. 5 ). Identification of these common findings is helpful with diagnosis and treatment planning. Soft tissue lacerations, if present, likely indicate an area of direct force. Edema may alert the clinician to the region of likely fractures, but may also obscure any change in facial width or projection. Nasal bleeding is common to midface fractures because of the disruption of the nasal septum and mucosa. Pain, ecchymosis, and bony steps along the fractures lines may be appreciable on visual inspection and palpation. In addition, a change in occlusion is often found.
For LeFort I fractures, maxillary mobility may be present. However, the absence of mobility does not preclude a fracture. If the maxilla has been impacted, there may be no mobility and the anterior facial height may be decreased. There is typically an anterior open bite caused by the posterior and inferior force placed on the maxilla by the medial and lateral pterygoid muscles. Ecchymosis in the region of the greater palantine foramen, or Guerin sign, and ecchymosis in the buccal vestibule also indicate a LeFort I fracture.
LeFort II fractures typically present with periorbital and subconjunctival ecchymosis in addition to the findings outlined earlier. A bony step at the infraorbital rim may also be detectable. Disruption of the infraorbital nerve leads to anesthesia of the upper teeth, gingiva, upper lip, and lateral aspects of the nose. If the orbital floor has been disrupted with entrapment of the inferior rectus, diplopia with restricted superior gaze is present. If the nasal bones and maxilla are mobile, a LeFort II fracture should be suspected. A dish-faced appearance may be present as a result of decreased nasal projection. In addition, rhinorrhea of the cerebrospinal fluid (CSF) may be present, suggesting a basilar skull fracture with involvement of the dura.
LeFort III fractures involve mobility of the maxilla, nasal bones, and zygomas as a single unit. A palpable bony step may be present at the zygomaticotemporal or zygomaticofrontal suture. As with LeFort II fractures, bilateral periorbital edema (raccoon eyes) and CSF rhinorrhea may be present. Lengthening of the facial height, orbital hooding, and enophthalmos are also typically present. Ecchymosis over the mastoid region (Battle sign) may be present, in addition to CSF otorrhea and hemotympanum.
Features of the clinical examination should be supported by the radiographic examination. A CT scan of the head and maxillofacial region detects fracture lines, bony displacement, air-fluid levels in the paranasal sinuses, orbital entrapment, and intracranial involvement. They provide exquisite detail and have revolutionized the diagnosis of specific fracture entities.
Surgical treatment and postoperative management
The goals of treatment of midface fractures are to restore function and esthetics. In terms of function, reestablishment of the preinjury dental occlusion is essential. By reconstructing and stabilizing the vertical and horizontal buttresses of the midface, occlusal forces can be tolerated and facial height, width, and projection can be restored.
The timing of repair for maxillary and midfacial fractures is often a source of debate. Although early repair may facilitate reduction, the patient’s systemic status may prevent surgical correction in the first few days after the injury. It is therefore more common to complete the definitive fracture reduction and fixation after the patient has been stabilized, a definitive airway (if necessary) has been placed, and the patient’s edema has begun to resolve. This strategy gives the maxillofacial surgeon time to review all of the relevant clinical and radiographic data and plan surgery that best treats the patient’s needs. We believe the ideal timing of surgery to be between 7 and 10 days after trauma. At this point, the bulk of edema has resolved and the fractures are still simple to mobilize and reduce. Beyond 10 days, reduction may become more difficult because of osseous healing and fibrosis. There are obviously exceptions to this rule, such as orbital entrapment and hemorrhage control. The timing of surgery is patient-specific and must take all factors into account.
A stable airway must be secured for repair of midface trauma. For most LeFort I fracture cases, a nasoendotracheal tube can be placed by the anesthesiologist, with fiber-optic guidance, if necessary. A nasoendotracheal tube may interfere with LeFort II and III level fractures because of the involvement of the nose. Also, in cases involving basilar skull fractures, there may be hesitancy to place a nasal tube for fear of intracranial intubation. In these cases, an oral endotracheal tube can be placed behind the existing dentition or through dental gaps. If this procedure is not possible, a submental intubation technique can be used. It is important that the patient’s final occlusion can be established without interference from the endotracheal tube. In certain cases, a tracheostomy may be indicated. Examples of these cases include patients with cervical spine injuries and patients requiring prolonged ventilatory support.
In cases involving fractures with minimal displacement and no change in occlusion, no treatment other than a nonchew diet for approximately 4 weeks may be indicated. However, these cases are rare. The ideal repair of maxillary and LeFort level fractures involves open reduction. When open reduction is not possible, closed reduction techniques involving maxillomandibular fixation (MMF) for a period of 4 to 6 weeks can be used. In cases in which there is displacement of the maxilla with an occlusal discrepancy, Rowe disimpaction forceps can be used to mobilize and reduce the maxilla ( Fig. 6 ). With closed reduction, facial height, width, and projection are based off the dental occlusion. Because there is no direct visualization of the fractures, it is difficult to control the vertical position of the maxilla, and autorotation of the maxillomandibular unit may lead to a change in facial height and projection. The severely comminuted midface injury may also create a challenge for open reduction. In patients who cannot undergo autogenous grafting or for those who do not tolerate MMF because of medical or psychological reasons, external fixation with a halo head frame can be used.
Despite these exceptions, the most common treatment of maxillary and LeFort fractures remains open reduction with internal fixation. The general treatment approach involves:
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Exposure of the fractures
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Mobilization and reduction of fracture segments
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Establishment of occlusal relationships (MMF)
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Rigid or semirigid fixation
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Bone grafting when necessary
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Resuspension/repair of soft tissue injuries
Our preference is to place Erich arch bars before the surgical incision. Any modality for MMF can be used if a stable occlusion can be attained. It is our experience that arch bars provide the most stability and ease of reduction when placing patients into MMF. They also provide the most control over the occlusion in the postoperative period.
The most common approach for exposure of a LeFort I level fracture is the buccal vestibular incision ( Fig. 7 ). This incision extends from 1 zygomaticomaxillary buttress to the other at a level approximately 5 mm superior to the mucogingival junction. Excellent exposure of the nasomaxillary buttresses, zygomaticomaxillary buttresses, and the anterior and lateral walls of the maxillary sinus is attained. Dissection up to the inferior orbital rims is possible through this approach, if necessary. Once exposed, the fractures are mobilized using Rowe forceps. Alternatively, an instrument such as a Tessier mobilizer can be placed behind the maxillary tuberosity to apply anterior and medial force to the impacted maxilla. Once the bony segments are mobilized, the patient is placed into MMF. The maxillomandibular unit is then rotated in the glenoid fossa, making sure that the mandibular condyle is passively seated and the fractures are reduced. Failure to properly seat the condyle before fixation causes a class II malocclusion, with an anterior open bite on the affected side on release from MMF (assuming a class I preinjury occlusion). Next, the fractures are fixated with either bone plates or interosseous wiring. The fixation pattern and method are dependent on the specific fracture location and bone available. The most common method is to use 4-point fixation at the zygomaticomaxillary and nasomaxillary buttresses with 1.5-mm to 2.0-mm miniplates ( Fig. 8 ). If bony gaps exist, autogenous grafting can be used ( Fig. 9 ). The patient is then released from MMF, the occlusion is checked to confirm reproducibility, and the wounds are closed.
Open reduction of LeFort II fractures may require fixation across the infraorbital rim or the nasofrontal region. If possible, 3-point or 4-point fixation is ideal. The buccal vestibular incision described earlier can be used to expose the zygomaticomaxillary buttresses. The decision to expose the infraorbital rim is often dependent on a palpable step or cosmetic deformity in the rim or in cases in which orbital floor exploration and reconstruction is indicated (ie, orbital floor blow-out with enophthalmos or entrapment). The infraorbital rim can be accessed via a transconjunctival, subciliary, infraorbital, or lower lid approach. Each has distinct advantages and disadvantages, which are discussed in a later section. Once the rim is exposed, the fractures are mobilized and reduced as described earlier, and a 1.0-mm to 1.3-mm plate can be placed for fixation. The nasofrontal region can be exposed via an existing laceration, bilateral lynch incision, open-sky approach, or coronal incision. These approaches are discussed later. A low-profile plate (1.3 mm) can then be placed for fixation.
Open reduction of a LeFort III fracture requires exposure of the zygomaticofrontal suture in addition to those discussed earlier. Plates of at least 1.3-mm strength should be placed to fixate this area. The coronal flap provides excellent exposure of this area in addition to the nasofrontal region and is the preferred approach. Alternatively, an upper lid (blepharoplasty) or lateral eyebrow incision can be used to access the zygomaticofrontal suture. This approach, in combination with the approaches to access the nasofrontal region and zygomaticomaxillary buttresses, can expose all of the areas needed for fixation. We prefer to sequence fracture fixation from top-down and outside-in.
When extensive subperiosteal dissection is performed in the midface, ptosis of the midfacial soft tissue may result if it is not resuspended. Midface periosteum can be resuspended to the orbital rim and the lateral and temporal soft tissue can be resuspended to the temporal fascia or temporal or parietal bone.
Postoperatively, patients are kept on a nonchew diet for 4 to 6 weeks. The patient should avoid any occlusal force that could cause micromovement across the fracture lines. The arch bars are kept in place during this period and light guiding elastics can be used to control the occlusion. There is controversy over whether antibiotics should be used in the postoperative period. Some advocate only a single preoperative dose of antibiotics, unless there is an existing infection or if the inciting trauma caused a contaminated wound. Others have promoted the use of postoperative antibiotics for 7 to 14 days. We prefer a 7-day course of antibiotics, with broad spectrum coverage to include oral and sinus flora (ampicillin and sulbactam, amoxicillin and clavulanate). Patients can also be placed on a decongestant and oxymetazoline nasal spray to encourage drainage of the maxillary sinus. Patients should be counseled about sinus precautions, proper nutrition, and limitation of physical activity. At the end of the 4-week to 6-week period, the stability of the maxilla is assessed. If stable, the arch bars are removed and the patient’s diet and activity level are slowly advanced.
Palatal fractures
Classification
Palatal fractures occur in approximately 8% of LeFort fractures. They rarely occur as an isolated fracture. Some have advocated dividing theses fractures into specific groups based on the location of the fracture in relationship to the maxillary alveolus, teeth, and palatal midline ( Fig. 10 ).
Diagnosis
A palatal fracture should be expected when there is disruption of the palatal and gingival mucosa. Other clinical signs may include a change in occlusion, mobility of alveolar segments, or a palpable bony step in the palatal vault ( Fig. 11 ). A CT scan with axial and coronal slices should be acquired to confirm the diagnosis.
Surgical treatment and postoperative care
Treatment of palatal fractures may involve a combination of arch bars, rigid internal fixation and palatal or occlusal splints. Consideration of associated mandibular and midfacial fractures should determine the approach and sequencing. The goal of treatment is to reproduce the preinjury occlusion. Hendrickson and colleagues (1998) described a step-wise treatment algorithm based on the fracture type. Those fractures involving the anterior alveolus (type Ia) and posterolateral alveolus (type Ib) are treated with a segmental arch bar spanning the teeth adjacent to the fracture lines. In addition, when possible, miniplates can be placed in the region of the nasomaxillary buttress (Ia) and zygomaticomaxillary buttress (Ib) to further stabilize these fractures. A period of 2 to 4 weeks of MMF is recommended. Types II, II, IV, and VI fractures are treated with a combination of arch bars and rigid internal fixation. An arch bar is first loosely applied to achieve preliminary alignment of the segments. Next, the patient is placed into MMF to determine occlusal accuracy. The patient is then released from MMF and the palate is exposed via an existing laceration or longitudinal incision, paying close attention to the protection and preservation of the greater palantine vessels. After exposing the fracture, a minimum of 2 plates are applied to prevent posterior splaying of the segments. This procedure is best performed while applying medial pressure from the lateral sides of the segments. The wound is then closed and the patient is placed back into MMF. The nasomaxillary and zygomaticomaxillary buttresses is then exposed, with rigid internal fixation as necessary. The occlusion is checked and the patient is placed into MMF for 2 to 4 weeks. Comminuted (type V) fractures are treated with a palatal acrylic splint. Incisions should be avoided to preserve the blood supply to the bony fragments. The splint is fabricated after preoperative model surgery on dental casts to determine the desired occlusal relationship and then wired into placed for approximately 6 weeks. These splints can be placed with or without arch bars. Alternatively, for all fracture types, practitioners familiar with model surgery can fabricate an occlusal splint before surgery. Here, fracture reduction relies on the clinician’s preoperative estimate of the preinjury occlusion. The splint should be left in for a minimum of 6 weeks and should be supported by rigid internal fixation at the LeFort I to III levels, as necessary.
Postoperatively, patients should be kept on a soft diet for 4 to 6 weeks. When arch bars are in place, guiding elastics can be used after MMF is released.
Zygomaticomaxillary complex fractures
Anatomy
The zygomas are a major determinant of facial symmetry and form. The zygoma has been described as a quadrangular bone with 4 processes. It articulates with the maxilla, temporal, sphenoid, and frontal bones ( Fig. 12 ). The sutures created by these articulations are common points of fracture ( Fig. 13 ). The anatomy of the zygoma and its 4 articulations described earlier have led to terminology such as zygomatic complex and zygomaticomaxillary complex (ZMC) to describe fractures of this region. Appropriate reduction of the zygomaticosphenoid, zygomaticofrontal, and zygomaticomaxillary articulations are critical to the correct alignment of the fractured zygomatic complex. Because of the multiple articulations of the zygoma and proximity to the orbit, it has been estimated that 76% of fractures involving the zygoma also involve a portion of the orbital wall or floor.
