HPI
A 48-year-old male presents to the emergency department with nonresolving left facial pain after an assault 2 weeks earlier. The patient reports he was repeatedly punched in the left face during an altercation. The mechanism of injury is an important consideration because the direction and magnitude of force help to direct the clinical examination. The patient denies loss of consciousness or amnesia. He has not experienced dizziness, headaches, nausea, or vomiting since the altercation. He reports initial swelling and bruising of the left cheek that has resolved. Since the assault, he has had difficulty opening his mouth and has had throbbing left facial pain on function, both while eating and speaking. The patient denies visual acuity changes; has no alteration in hearing; and has had no discharge from the ears, eyes, or nose.
PMHX/PDHX/medications/allergies/SH/FH
The patient has a past medical history significant for hypertension controlled with ramipril. He denies additional medications, has no known drug allergies, and has no past surgical history. He is a general laborer, reports 30 units of alcohol weekly and a 20 pack-year history of smoking, and denies the use of recreational drugs.
Examination
Although the patient has an old injury, the appropriate Advanced Trauma Life Support protocol has been completed with no significant findings other than the maxillofacial injuries you have been consulted to manage. Cervical spine and intracranial extension of the injury have been ruled out by the trauma team. The patient is hemodynamically stable, resting comfortably on examination, and is awake, alert, and oriented with a Glasgow Coma Scale score of 15.
Maxillofacial . There are no findings suggestive of basal skull fracture (rhinorrhea, otorrhea, Battle’s sign, raccoon eyes) and no visible lacerations, abrasions, or contusions. Cranial nerves II to XII are intact bilaterally (left maxillary nerve hypoesthesia would indicate potential orbital floor or zygomaticomaxillary complex [ZMC] fractures). There is facial asymmetry with a visible and palpable depression of the left zygomatic arch that that is tender when examined. A palpable bony step defect can be appreciated. There are no hearing deficits. On otoscopic examination, the tympanic membrane is intact, and the external auditory canal is clear with no hemotympanum. All visual fields are intact with symmetric and normal extraocular movement and no diplopia or changes in visual acuity. The pupils are equal, round, and reactive to light. There is no hyphema, chemosis, or subconjunctival hemorrhage. The supraorbital and infraorbital rims are intact with no palpable step deformities. The patient denies retrobulbar pain. There is no orbital dystopia. Nasal airflow is subjectively unchanged bilaterally. There is no crepitus, mobility, or steps of the bony and cartilaginous nasal structures. The nasal septum is deviated right on anterior rhinoscopy. There is no septal hematoma or perforation. There is no tenderness to palpation overlying the cervical vertebrae; there is no palpable adenopathy; and head flexion, extension, and rotation are grossly normal. Maximum interincisal opening is 15 mm (arch impingement on the temporalis muscle and coronoid process). The maxilla, mandible, and dentoalveolar segments are stable with no signs of trauma. The occlusion is stable bilaterally. There are no mucosal defects intraorally, and there is no visible ecchymosis of the maxillary vestibule or palate. The oropharynx is patent and symmetrical. The floor of the mouth is soft and not elevated.
Imaging
The emergency department team obtained a computed tomography (CT) scan of the facial bones with 1-mm slices ( Figs. 52.1 and 52.2 ) demonstrating a displaced left zygomatic arch fracture. There was no evidence of a ZMC fracture, orbital fracture, or concomitant mandibular fracture. A variety of imaging modalities are available to evaluate zygomatic arch fractures. CT remains the gold standard to comprehensively evaluate the maxillofacial skeleton in the setting of facial trauma. Coronal, sagittal, and axial views allow the examiner to determine the fracture planes, degree of displacement, and amount of comminution. Before the advent of CT imaging, plain film radiography was used routinely to assess zygomatic arch fractures. The Waters view provides imaging of the midface, including the orbital rims, body of the zygoma, and zygomatic arch, and the submentovertex (jug-handle) images the submandibular region to vertex of skull, allowing visualization and identification of zygomatic arch fractures.
Assessment
A 48-year-old male with an isolated displaced left zygomatic arch fracture after repeated strikes to the left face during an altercation approximately 2 weeks ago.
Discussion
The zygoma is a quadrangular-shaped bone that articulates with the maxillary, frontal, sphenoid, and temporal bones. The zygomaticotemporal (ZT) suture is formed by the articulation of the temporal process of the zygomatic bone and the zygomatic process of the temporal bone. The zygomatic arch contributes to facial width and serves as an attachment for the masseter muscle. The point in the arch that is least resistant to fractures is located roughly 1.5 cm posterior to the ZT suture. Zygomatic arch fractures commonly occur in combination with fractures of the ZMC. Isolated zygomatic arch fractures are reported to occur in 5% to 14% of all zygomatic fractures. Displaced zygomatic arch fractures may impinge the coronoid process, resulting in trismus and associated functional limitations. Long-term functional consequences of poorly managed arch fractures include persistent impaired mouth opening, ankylosis of the coronoid process and fractured segments, and facial nerve palsy. Aesthetic concerns resulting from displaced zygomatic arch fractures include lateral midface depression ( Fig. 52.3 ) and facial asymmetry. Depending on the patient’s compliance and comorbidities as well as concomitant injuries, those with zygomatic arch fractures can be treated under local anaesthetic, intravenous sedation, or general anesthesia.
