Abstract
Panfacial injury refers to fractures present in the cranio-orbital (upper third), orbitozygomaticomaxillary (middle third), as well as the mandibular (lower third) portions of the craniofacial skeleton. These injuries present challenges in surgical management to avoid long-term sequelae of inadequate correction, including increased facial width, enophthalmos, facial retrusion, and malocclusion. The purpose of this chapter is to provide an algorithm for management of these panfacial injuries in order to optimize outcomes.
Keywords
panfacial fracture, facial trauma, facial fracture, pediatric facial trauma, craniofacial surgery
Background
A panfacial craniofacial injury refers to fractures present simultaneously in the cranio-orbital (upper third), orbitozygomaticomaxillary (middle third), as well as the mandibular (lower third) portions of the craniofacial skeleton ( Fig. 1.19.1 ). This requirement of panfacial injuries to have fractures present in all three levels of the face is not consistently used among trauma studies, with some authors including patients with severe injury in only two levels. The incidence of panfacial injury ranges from 0.8% to 3% in large craniofacial fracture series, and can occur from a number of mechanisms, including blunt, penetrating, and avulsive mechanisms in all age groups. These injuries present challenges in surgical management to avoid long-term sequelae of inadequate correction, including increased facial width, enophthalmos, facial retrusion, and malocclusion ( Figs. 1.19.2 and 1.19.3 ). The purpose of this chapter is to provide an algorithm for management of these panfacial injuries in order to optimize outcomes.
Surgical Anatomy
Due to the multiple components and steps in acute surgical correction of panfacial fractures, it is imperative always to remember the overall goals of increasing facial projection, decreasing facial width, restoring functional and symmetric globe position, and restoring optimal occlusion. These goals can be lost during the focus on individual fractures during a prolonged surgery, after which each individual fracture may appear well reduced, but the overall esthetic result is suboptimal. Understanding, identifying, and restoring reliable transverse and vertical facial buttresses rather than reducing single fracture lines is paramount to achieving a favorable three-dimensional outcome ( Fig. 1.19.4 ).
Clinical Presentation
Patients with panfacial injuries have sustained a degree of trauma that results in multiple potential associated injuries. All patients must undergo full multidisciplinary ACLS staged assessment to rule out other associated life-threatening conditions before focusing on the specific facial injuries. Intracranial, cervical spine, thoracic, abdominal, and severe extremity injuries must be ruled out or treated before the patient will be stable enough for craniofacial reconstruction. Although many facial injuries can be surgically treated acutely at the time of presentation before swelling occurs, panfacial injuries typically require days, and in rare cases weeks, before stabilization allows clearance for the craniofacial team to treat the facial injuries. Life-threatening acute facial bleeding will require a staged escalating algorithm for treatment in these patients along a spectrum from compressing and packing to interventional radiology embolization.
Radiological Evaluation
Due to the high incidence of internal carotid injuries in high sub-cranial fractures, it is our protocol to perform CT angiography on all panfacial injuries. High-definition, thin-slice CT scans with three dimensional reconstructions are invaluable in evaluation, surgical planning, and subsequent long-term management of panfacial fractures. Additionally, intraoperative CT scanning, when available, can be useful for assuring accurate placement of orbital implants at the time of surgery ( Fig. 1.19.5 ). Although stereotactic navigation and computer generated models are useful in secondary corrections of complex cases, they are not usually readily available for acute treatment.
Presurgical Preparation
Prior to commencing surgical treatment of a panfacial injury, preoperative considerations include perioperative airway management, cervical spine precautions, anesthetic/transfusion plans, surgical team composition, as well as preparation for anticipated adjunctive techniques, such as pericranial flaps, bone graft donor sites, and need for free-tissue reconstruction. A number of options for airway management are available and should be considered, including oral, nasal, submental, and tracheal airways. The entire team should identify the key milestones of treatment at the beginning of surgery, as well as a plan to cycle team members to prevent fatigue and optimize efficiency.
Surgical Techniques
When considering the sequence for fracture reduction and fixation, it is important follow a vertical and horizontal system of reconstruction as guided by the vertical and horizontal facial buttresses. A number of systems (top-down vs. bottom-up; outside to inside vs. inside to outside, etc.) have been proposed. Each approach has merits, and most experienced trauma teams will be comfortable with more than one sequence of treatment which they will interchange depending on the specific pattern and differential degrees of injury in the regions of the face. For this chapter, we will describe the 11 steps of a top-down, outside-to-inside approach that is the most commonly used at our institutions ( Table 1.19.1 ). It is important to emphasize that most panfacial injuries will require autologous bone grafts and/or vascularized pericranial flaps at some step of the surgery, therefore care must be taken to ensure that these resources are available during prepping and draping of the patient and during the initial dissection.
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Step 1: Expose All Treatable Fractures
The cranium, nasofrontal, zygomatic arch, lateral orbital rims, and medial orbital wall regions can be best exposed with a coronal incision. Lower eyelid incisions facilitate orbital floor exposure as well as visualization of the upper transverse and vertical facial buttresses. Upper and lower gingivobuccal sulcus incisions will allow access to the transverse buttresses of the maxilla and anterior mandible. Posterior mandible skin incisions such as the Risdon approach or retromandibular approach may be required for complex angle or condylar fractures in order to achieve reliable reconstruction of the posterior vertical buttress of the mandible ramus ( Fig. 1.19.6 ). Parasagittal palate incisions may be required to reestablish the posterior maxillary width if a reliable mandible arch is not available as a reference. Incisions should be tailored to individual patient patterns of hair loss and preexisting lacerations, which can provide excellent access and should always be considered in surgical planning.
Step 2: Establish Skullbase and Fronto-Orbital Bandeau References
The anterior skullbase and fronto-orbital region serves as a reliable reference in all but the most severe panfacial fractures. Fractures in this region should be plated and the supraorbital bar reduced and fixated to serve as the foundation for reconstruction of subcranial skeleton. If this reconstruction is done inaccurately, it will create a domino effect of a series of malreduced subcranial fractures. The goals of skullbase and frontal treatment include sealing the sinuses from the cranium, prevention of pulsatile enophthalmos by rigid correction of the superior orbit, and preservation/correction of orbital volume. It is paramount to ensure that bone grafts to the superior orbit are not positioned too low, and are rigidly fixated ( Fig. 1.19.7 ). Sphenoid fractures are an indication of high velocity injury, and require reduction to decompress the orbital apex as well as create a reliable reference for reduction of the zygomas. Rigid fixation of anterior cranial base or orbital roof grafts is required to prevent inferior migration from pulsation of the brain postoperation, as well as to allow salvage of the grafts in case of intracranial infection and the need for a surgical washout. Cranial bone segments should maximize bone-to-bone contact at as much of the perimeter of the fracture segments as possible. This may necessitate leaving bony gaps at other portions of the fracture in order to optimize contact elsewhere. This is preferable to positioning calvarial bone at the center of the skull defect with equal circumferential spacing, which is essentially creating a sequestra and will lead to nonunion, resorption, and/or infection. A small intentional bony gap is left, however, between the superior orbital rim and the frontal craniotomy bone in the cases where a pericranial flap is placed through the gap to provide soft tissue seal of the anterior cranial fossa.