Fractures of the pediatric midface are infrequent, particularly in children in the primary dentition, due to the prominence of the upper face relative to the midface and mandible. With downward and forward growth of the face, there is an increasing frequency of midface injuries seen in children in the mixed and adult dentitions. Midface fracture patterns seen in young children are quite variable; those in children at or near skeletal maturity mimic patterns seen in adults. Non-displaced injuries can typically be managed with observation. Displaced fractures require treatment with appropriate reduction and fixation and longitudinal follow-up to evaluate growth.
Key points
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Fractures of the pediatric midface are relatively infrequent.
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Midface fracture patterns seen in children in the primary and mixed dentition are highly variable.
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Fracture patterns seen in adolescents and teenagers more closely resemble those seen in adults.
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Operative intervention should be considered for management of displaced fractures in children.
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Longitudinal follow-up to assess dental and facial development is critical.
Introduction
Pediatric facial fractures make up fewer than 15% of all facial fractures and comprise less than 5% of pediatric trauma admissions in the United States. Midface fractures are not commonly seen in patients younger than 5 years of age.
In infants, the cranium protrudes forward in comparison to the remaining bones of the face. Given the relative retrusion of the facial skeleton relative to the cranium, there is a much lower risk of facial fractures in infants and small children. , As children age, the craniofacial skeleton develops further, with downward and forward growth of the midface and mandible resulting in increased prominence of these portions of the face. At birth, the ratio of skull to face surface areas is projected to be about 8:1. As the child develops, the ratio shifts until it reaches 2:1 in adulthood. , This change in ratio reflects the skull increasing to 4 times its original size, whereas the face increases to 12 times its original size. The differential distribution of facial ratios in infants and young children relative to skeletally mature patients accounts for the difference in prevalence of facial fractures seen across these groups ( Figs. 1 and 2 ). Although the nomenclature for midfacial fractures is consistent between children and adults ( Fig. 3 ), the patterns of injury may be more variable in growing children ( Figs. 4–9 ).
Anatomy
In comparison to the adult facial skeleton, children demonstrate increased bone pliability, unerupted teeth, incompletely developed sinuses and a thicker layer of subcutaneous fat. These factors render children more likely to absorb greater energy transfers without sustaining displaced facial fractures. The lack of a fully developed frontal sinus results in less potential for shock absorption from blunt force trauma. This, in turn, allows for the frontal force to be transmitted to the supraorbital bar, basilar, skull and intracranially. Beginning at 2 years of age, the ethmoid and maxillary sinuses begin to enlarge, and the sphenoid and frontal sinuses begin to appear. The sinuses continue to grow, reaching full size after adolescence. As the sinuses develop, the bone of the midface begins to thin, providing decreased resistance to fracture when compared to infancy. Additionally, the flexible nature of pediatric bones gives children a greater likelihood of sustaining greenstick fractures. , As children approach skeletal maturity, the differences between pediatric and adult facial skeletons are minimal.
Common Etiologies
Children are less apt to sustain serious midface trauma with blunt force frontal impact, given their anatomy. Midface fracture patterns in infants and small children are typically the result of high-energy transfer mechanisms, such as motor vehicle accidents. As children grow, fracture etiologies begin to more closely resemble those in adults: motor vehicle accidents, sports, and assault.
Initial Evaluation
As with any trauma patient, adherence to Advanced Trauma Life Support (ATLS) principles is paramount in the evaluation of the injured child. , One should ensure that the patient’s airway is evaluated and free of any obstructions. Additionally, the patient’s cervical spine should be assessed, and patient should remain in a rigid collar to allow for stabilization until cervical spine injury can be ruled out. Given that pediatric midface fractures are typically seen in cases with high velocity impact, patients may be intubated upon arrival to the hospital. However, if this is not the case, upon initial assessment, the airway should be immediately evaluated. If the patient is unable to maintain their airway independently, orotracheal intubation should be considered. If orotracheal intubation is unable to be achieved, one can consider cricothyroidotomy in an emergency setting. If an obstruction is present to the lower airway, an emergency tracheostomy can be considered. Once an airway is definitively established, primary survey per ATLS protocol should be completed.
Evaluation of the facial skeleton remains a part of the secondary survey after airway, breathing, circulation, disability, and exposure are addressed. Patients with midface trauma will benefit not only from evaluation by the maxillofacial trauma surgeon, but also from evaluations by Ophthalmology to rule out ocular injury in patients with fractures involving the orbit (Le Fort II, Le Fort III, zygomaticomaxillary complex [ZMC], and naso-orbito-ethmoid [NOE]) and neurosurgery if skull fractures or intracranial injury is evident or suspected.
Treatment Considerations: General Principles
Management of pediatric facial injuries requires an understanding of the natural growth and development of the facial skeleton. Although the goals of treatment of displaced facial fractures are the same as in adults, reduction into anatomic alignment and immobilization to allow for fracture healing, the methods by which these are achieved may need to be modified. Surgical exposures should be tailored to minimize subperiosteal dissection to only that needed to visualize the fracture and, if needed, apply fixation. When considering fixation, both titanium and resorbable fixation may be considered appropriate in contemporary practice. Fixation should be placed with recognition of the location of succcedaneous teeth ( Fig. 10 ). Titanium fixation may afford the opportunity for greater rigidity with lower profile plates, but comes at the cost of the need for removal after bony healing in growing patients. Resorbable fixation devices have become more popular in this context, but may be less rigid and require thicker fixation plates. However, as children have much more robust healing than adults, the paradigms for rigid fixation of the adult facial skeleton may not apply to children. Less rigid fixation may result in sufficient immobilization to allow for bony union.
Timing of repair is challenging given the quick healing nature of pediatric tissues. Ideally, one should pursue operative management within 1 week of injury, with some authors suggesting repair as soon as 2 to 4 days after injury.
Le Fort fractures
Anatomy
The classic Le Fort fracture patterns as described by Rene Le Fort in 1901 are less commonly seen in children given the relative pliability of pediatric skeletal structure when compared to that of adults (see Figs. 4 and 5 ). In general, Le Fort fracture patterns are rarely seen in children under the age of 6 years. Previous studies have reported that children with mixed or solely primary dentition do not sustain Le Fort type fractures. However, this notion has been disputed by some authors who have noted equal distribution of Le Fort type fractures among children with primary, mixed, secondary dentition. In general, the likelihood of sustaining a Le Fort type fracture pattern is greater in older children compared to infants and young children. Pediatric patients most commonly sustain Le Fort type fractures in cases of high velocity impact, such as in motor vehicle accidents. , ,
Classification
A common component of all Le Fort fractures is disruption of the pterygomaxillary junction. The Le Fort I fracture pattern results from a horizontal force delivered to the level of the patient’s dentition. The Le Fort I fracture pattern involves separation of the lower midface (maxilla and alveolus) from the zygoma and nasal complex, as the fracture extends laterally from the zygomaticomaxillary buttress to the nasomaxillary buttress at the level of the piriform rim. The Le Fort II fracture (“pyramidal fracture”) pattern extends from the nasofrontal suture down through the zygomaticomaxillary suture, with the resultant fractured segment resembling a pyramidal structure. The Le Fort III fracture (“craniofacial disjunction”) pattern is noted to produce a convex or dish-shaped facial deformity. It extends from the nasofrontal suture through the floor of the orbit, and fractures at the lateral orbital rim, and zygomatic arch.
Clinical Examination
When evaluating patients for Le Fort fracture patterns, it is important to evaluate for potential hemorrhage, although midface trauma is unlikely to be the sole cause of hemodynamic instability. If persistent bleeding is present, the region should be packed if immediate control of the vessel is unable to be achieved. Continued hemorrhage that is unable to be controlled with packing may warrant operative exploration or angiography and embolization. Once bleeding is controlled, the provider should perform a thorough facial examination.
One should take note of any external lacerations present, document the depth of injury and involved tissues. Any obvious depression or displacement of the patient’s skeletal structure is suggestive of displaced facial bone injury. Patterns of ecchymoses may correspond with particular injuries, such as postauricular ecchymoses with skull base fractures (Battle’s sign), periorbital ecchymoses with NOE fractures, and palatal/mucosal ecchymoses with maxillary fractures (Guerin’s sign). Next, assess for bleeding or drainage from the patients ears and nose. If clear drainage is noted within either the ear canal or nose, cerebrospinal fluid (CSF) leak should be suspected, and neurosurgical evaluation requested. The patient should also be asked if they have a metallic or salty taste, as this can be another indication of a CSF leak. Intranasal examination should include assessment of bleeding, septal deviation, or hematoma.
One should then systematically palpate the bones of the face starting from top to bottom to assess for any step offs. Palpate the superior rims of the orbits, followed by the lateral rims, the inferior rims, nasal bones, and zygomas. Next, assess for any mobility of the maxilla by placing the index finger on the anterior palate and the thumb within the labial vestibule and pulling inferiorly, anteriorly, and laterally. The provider should assess intraorally for any lacerations, displaced teeth, or region of ecchymosis.
Management
Management of pediatric Le Fort type fractures is debated, though most clinicians favor early surgical repair for displaced fractures. Operative management is typically pursued as these fractures tend to have more complicated fracture patterns given the mechanism of injury. However, some authors argue that given the increased osteogenic potential of the pediatric skeleton, many facial fractures can be managed conservatively when compared with their adult counterparts. Ultimately, most providers tend to treat Le Fort type I fracture patterns operatively. ,
Regardless of the level of the Le Fort injury, management will frequently include reduction of the occlusal unit and application of intermaxillary fixation. Intermaxillary fixation in children may be challenging due to the incomplete eruption of teeth, interdental spacing, and variable stability of primary teeth in the mixed dentition. The use of intermaxillary fixation screws or related appliances is strictly contraindicated in patients in the primary dentition and those in the mixed dentition in regions where the permanent teeth have not erupted.
Surgical approaches to Le Fort I fracture in children are similar to those in adults. Access to the nasomaxillary and zygomaticomaxillary buttresses is readily achieved via a maxillary vestibular approach. Patients with Le Fort II pattern injuries may require additional exposures of the infraorbital rim and/or nasofrontal junction. In isolated Le Fort II injuries, local incisions are suitable for accessing these areas. In patients with concomitant upper face injuries, a coronal exposure may be indicated. In addition to the exposures utilized for the central midface in Le Fort II fractures, exposure of the lateral orbital wall via upper eyelid approaches and zygomatic arch via a coronal approach, may be indicated in patients with Le Fort III injuries.
Zygomaticomaxillary complex fractures
Anatomy
Zygomaticomaxillary complex (ZMC) fractures are the most common fracture patterns associated with high impact traumas in children, with 15% of pediatric facial fractures being attributed to ZMC fractures (see Figs. 6 and 7 ). The next most common fracture patterns are maxillary dentoalveolar fractures, and nasal bone fractures. The anatomy of the ZMC involves the zygoma, the maxilla, and the orbital floor. The lack of pneumatization and the thicker walls of the pediatric sinuses allow for extra support to the zygomatic buttress, thereby producing an area of increased resistance to fracture. The increased cancellous-to-cortical bone ratio and flexibility at the suture lines provides another layer of protection to the ZMC region. As children age, the sinuses begin to develop, and the increased aeration to the maxillary sinuses, in addition to the eruption of the secondary dentition, causes growth of the midface and mandible, leaving the midface more vulnerable to fracture. In children, isolated zygomatic fractures rarely are seen as the bones surrounding the zygoma are very thin. The zygoma acts as a horizontal buttress, and with high velocity impact, will distribute the force to the adjacent bones, thereby resulting in concomitant fractures to the NOE complex, the orbit, and the skull.
Clinical Examination
The clinical examination for patients with suspected ZMC fracture patterns should start by evaluating for any obvious facial deformity to the malar eminences. One should make sure to evaluate from the superior, inferior, frontal, and lateral views to best assess for any displacement. The superior view is the best view to evaluate posterior displacement of the zygoma and potential for facial flattening. Next the provider should palpate starting at the medial portion of the inferior orbital rim, moving laterally toward the zygomatic arch, over the malar eminences, down toward the maxilla. As the ZMC involves the maxilla, it is also important to inspect and palpate intraorally, in the region of the buccal vestibule to assess for any regions of ecchymosis or dentoalveolar fractures, respectively.
Given that the orbital floor is typically involved in the fracture line, a thorough eye examination should be performed. Findings such as diplopia, unequal pupillary levels, enophthalmos, inferior displacement of the palpebral ligament, and subconjunctival hemorrhage may be seen. During the examination, the provider should also assess for full extraocular movements to ensure no signs of muscle entrapment. If full movements are not noted initially, one must perform a forced duction test to confirm restricted ocular movement. If there are any concerns during the eye examination, ophthalmology should be consulted for further evaluation. As the infraorbital nerve is often involved with these injuries, one may expect to find some degree of paresthesia present to the infraorbital region, maxilla and around the nose.
It is not uncommon to note periorbital ecchymosis, and as such it is also important to concurrently inspect for Battle’s sign by assessing behind the patient’s ears to note any hint of basilar skull fracture. If the zygoma is posteriorly displaced, one may note flattening of the malar eminences which can be best assessed from the superior view. The presence of edema may cause difficulties in assessment of malar positioning. Trismus may be seen in some patients as the zygoma may be displaced medially, thereby causing a physical stop for full opening of the mandible. As with any clinical exam, the provider should utilize radiographic imaging, specifically CT imaging, to create a complete inventory of the patient’s injuries.
Management
Management of ZMC fractures is divided as clinicians prefer to utilize conservative nonsurgical measures in pediatric populations so as not to disrupt midface and dental development. However, as ZMC fractures are typically seen with high velocity impact injuries, which also tend to produce more comminuted or displaced fractures, open reduction and internal fixation (ORIF) is often required to prevent future growth disturbances. ,
ORIF with miniplates and screws has become the standard of care for management of displaced ZMC fractures. During surgery, the surgeon must first ensure reduction of the spheno-zygomatic suture, as this allows for a more precise reconstruction with better aesthetic results. As with adult ZMC reconstruction, one must then ensure reduction of zygomaticofrontal suture, and the infraorbital rim, to ensure proper reduction before proceeding with fixation. The need for 1-, 2-, or 3-point fixation for adequate fixation will vary depending upon the degree of comminution and location of the fracture. ,
Surgical intervention should ideally be performed within 3 to 5 days after initial edema has resolved to avoid improper healing which may require reoperation. When performing exposure of the infraorbital rim through transconjunctival or transcutaneous approaches, it is paramount to resuspend the soft tissues of the midface to the rim following bony reduction. Failure to do so will frequently result in midface soft tissue ptosis and premature aging, as well as potentially contribute to lower eyelid malposition (ectropion).
Naso-orbito-ethmoid fractures
Anatomy
NOE fracture patterns involve the superior portion of the midface, specifically the nasal bones, the frontal bones, portions of the medial, superior and inferior orbital walls, and the ethmoid bones (see Figs. 8–10 ; Figs. 11–13 ). These fracture patterns in children are also typically only seen with high-speed velocity impact, such as in motor vehicle accidents, and tend to comprise less than 1% of pediatric facial fractures. , The NOE region is important as it is the physical junction between the forehead, nose, orbits, and upper midface. Injury to this area and subsequent operative treatment can make subsequent growth difficult to predict. With NOE fractures, the age of the child heavily influences fracture patterns, especially as children younger than 2 years old tend to have more flexible bones, leading to greater potential for greenstick fractures. It is also important to note that while the ethmoid, maxillary, and frontal sinuses are all present at birth, the frontal sinus only starts to develop when children are around 4 to 5 years of age. The lack of a fully developed frontal sinus leads to less potential for shock absorption from blunt force trauma. This can result in force being directed into the supraorbital region and skull base. For this reason, it is of utmost importance to consider intracranial hemorrhage and dural injury with associated CSF leak, especially in children who present with NOE fractures and basilar skull fractures.
