Associated Injuries

Whether the injured patient presents with an isolated maxillofacial injury or with multisystem involvement, the principles of treatment are the same. Establishment of a patent airway should be the most immediate concern. Control of hemorrhage from open wounds or bleeding orifices by pressure dressing or packing should be accomplished next. If shock is present, treatment should include rapid infusion of intravenous lactated Ringer’s solution followed by blood administration as soon as possible. Investigation for possible cranial, thoracic, or intraabdominal injuries should be completed before identifying the maxillofacial abnormalities.

Airway obstruction with subsequent hypoxemia can easily develop in the patient with a maxillofacial fracture. Blood clots, broken teeth or dentures, and foreign bodies, such as dirt or glass, can physically obstruct the airway. The posterior displacement of the tongue secondary to the patient’s position or to a mandibular fracture may occlude the airway. Other potential causes include glossopharyngeal edema and expanding hematoma. In all situations, a patent airway must take immediate priority. Sweeping debris from the oropharynx and mouth by using one’s finger may be a lifesaving technique. Suction, if available, is helpful. Simple traction on a posteriorly displaced tongue by suture or towel clip may alleviate obstruction. If these methods fail, oral intubation must be instituted. If facial edema, facial fractures, or cervical spine fractures prevent oral or nasal intubation, a cricothyroidotomy can be performed through the membrane between the thyroid and cricoid cartilages (Fig. 17-1). This site is a bloodless field, and the procedure can easily be done in the emergency department with only a scalpel. Later, an elective lower tracheotomy can be performed under controlled circumstances in the operating room. A low tracheotomy performed in the emergency department may be very hazardous and should be avoided.

Fig. 17-1 The site for cricothyroidotomy is located between the thyroid and cricoid cartilages.

Hemorrhage from open wounds can be controlled most easily by pressure dressings consisting of layers of gauze (Kerlix) and elastic bandages. Occasionally, an active bleeder in a facial wound may need to be clamped and ligated. However, blind clamping of possible bleeding sites is condemned because of the high incidence of iatrogenic complications, such as facial nerve damage. Nasal hemorrhage may require packing. Shock occurs very seldomly from an isolated maxillofacial injury and most commonly results from a thoracic or abdominal injury.

All patients should be considered candidates for cervical spine fractures, which occur in 4% to 7% of maxillofacial injuries. The initial examination should include palpation of the neck for tenderness over the cervical spine and evaluation of grip strength and motion in all extremities. Before other roentgenograms are taken, a cross-table lateral view of the cervical spine with all seven vertebrae visible should be examined for fracture or dislocation.

The evaluation and treatment of any associated life-threatening injuries that occur in the multiinjured patient must receive first priority. Subdural, epidural, or intracerebral hematoma may be present in a comatose or semilucid patient, indicating the need for skull roentgenograms and computerized axial tomographic scan. Possible chest injuries include rib fractures, pneumothorax or hemothorax, flail chest, aortic rupture, and pulmonary or cardiac contusion. Chest films and arterial gas studies may be indicated. Intraabdominal injuries, of course, would include a ruptured spleen, transected liver, major vessel injuries, and/or perforated intestine. A pregnant woman may suffer an abortion as a result of such an injury. Single or multiple extremity fractures may also be present. After repair and/or stabilization of the associated injuries has been accomplished, reduction of the maxillofacial fractures may be performed.

Examination and Diagnosis

An accurate history should be obtained whenever possible from the patient and/or witnesses at the scene of the accident. The type of accident, the patient’s position in the car, the use of safety belts, the mode of impact, and the patient’s condition at the time of injury are all important considerations in the initial assessment. Because alcohol is involved in 50% of automobile accidents, a blood alcohol sample should be drawn. Ingestion of other drugs should be considered by an appropriate drug screen analysis. A review of the patient’s past history should include other illnesses, previous surgery, allergies, and all current medications.

A diagnosis of facial bone injury can be established by three methods: observation, palpation, and radiologic evaluation. Moderate to severe facial edema may mask bony irregularities and asymmetries (Fig. 17-2). After resolution of the edema, facial asymmetry is suggestive of an underlying fracture. Light manual palpation is important in making the initial diagnosis.

Fig. 17-2 This 32-year-old man suffered a Le Fort III maxillary fracture, nasal fracturesa displaced mandibular fracture, and an undisplaced fracture of the seventh cervical vertebra. The nasal deformity is easily recognized, but the remaining deformities are masked by facial edema.

A systematic approach should be used routinely in examining all potential facial fracture patients. The boundaries of the orbit, the projection of the malar eminences and zygomatic arches, the maxillary and mandibular arches, and the nasal bones should be palpated. During examination, any depressions or step deformities should be noted, as well as any tenderness in areas of potential fracture.

Evaluation of the function of the extraocular muscles may demonstrate superior gaze impairment with subsequent diplopia. Orbital ridge or floor fractures commonly result in infraorbital nerve numbness of the cheek and the maxillary gingiva on the side of the fracture. Crepitus to light touch suggests fracture extension through the nasal airways or paranasal sinuses. Rhinorrhea confirms the involvement of the fracture through the cribriform plate. The presence of trismus may indicate a hematoma or contusion in the muscles of mastication or could suggest either zygomatic arch or mandibular fractures. A complete examination for possible facial injuries includes a thorough evaluation of dental occlusion for any abnormality. The oral cavity should be assessed, and any fractured or missing teeth should be located, if possible, and removed to avoid aspiration.

Radiographic assessment is extremely important in the evaluation of facial fractures. The studies available in most emergency departments should be considered a preliminary evaluation, which will be supplemented by more sophisticated techniques at a later date. Before any radiographs of the facial bones are undertaken, an evaluation of the cervical spine should be completed. Initially, a cross-table portable view of the cervical spine should be obtained to rule out the possibility of neck fracture. If this film is negative, a complete cervical spine series should be done. When this study shows no abnormality, then specific views of the facial bones can be done.

The Waters’ view is the single most informative roentgenogram in evaluation of the maxillofacial patient in the emergency department (Fig. 17-3). This study visualizes the floor and rims of the orbits, the walls of the sinuses, the zygomatic bones, the zygomatic arches, and the nasal septum with minimal interference of other bony structures. Opacity of a maxillary sinus suggests hemorrhage as a result of an orbital ridge and/or floor fracture. The Waters’ view requires the cooperation of the patient and a normal cervical spine, however, because the patient must be in the prone position during the examination. If the patient is comatose, uncooperative, or suspected of having a cervical fracture, a reverse Waters’ view with the patient in the supine position is a satisfactory substitute, because it gives almost the same level of detailed information. Other films worth consideration in the emergency department are the submental vertex view of the zygomatic arches and a mandible series. More sophisticated and detailed studies can be obtained later during the hospitalization or on an outpatient basis for isolated facial fractures.

Fig. 17-3 The Waters’ view is the best single roentgenographic study of the facial bones. It most clearly visualizes the rims of the orbits, the zygomatic bones and arches, and the maxilla. Note the clarity of the maxillary sinuses.

Since the development of computed tomography (CT) scanning, it has become essential for the diagnosis of facial trauma. The CT scan is a more accurate diagnostic study and allows an evaluation of complicated facial fractures before the resolution of edema. Additionally, injuries to the soft tissue structures in the area of trauma can be better evaluated— for example, the optic nerve or orbital herniation of the orbit (Fig. 17-4).

Fig. 17-4 Axial CT of the orbits clearly demonstrates the optic nerve and the medial and lateral rectus extraocular muscles.

The only disadvantage to the use of the CT scan is seen when artifacts caused by either dental fillings or metal appliances occur. Radiation is not considered a disadvantage; CT exposes the patient to a radiation dosage equal to the amount from linear tomography. Studies suggest that the amount of radiation from either study is less than the amount needed to cause cataracts.

The role of magnetic resonance imaging (MRI) in the craniofacial injury patient is primarily confined to evaluation of soft tissue trauma. When injuries to the ocular structures are noted and disturbances of vision are present, MRI may help localize the site of the injury (Fig. 17-5).

Fig. 17-5 MRI of the orbits shows a large hematoma along the roof of the left side, which displaces the globe inferiorly. The eye was blind on initial examination.

Fractures of the Mandible

Although it is the thickest and heaviest of the facial bones, the mandible is the second-most commonly fractured (after nasal bones). Mandibular fractures may occur as isolated injuries or as components of complex maxillary and mandibular fractures. The most common causes of mandibular fractures are acts of violence that may range from simple falls to motor vehicle accidents. Occasionally, systemic diseases such as hyperparathyroidism and osteomalacia may predis pose to mandibular fractures. Infrequently, benign or malignant tumors, cysts, or osteomyelitis may precipitate such fractures.

Factors influencing the severity of the displacement of the fracture segments are multiple and interrelated. The direction and intensity of the force of injury cause different fractures. High-velocity injuries cause a fracture at the site of impact, whereas a slow, less violent force not only causes a fracture at the impact site but also may fracture the opposite condylar neck. A blow to the area of the symphysis may cause fractures of both condylar necks. Second, the site of the fracture may influence the amount of displacement of the segments, depending on the direction of the fracture line and the direction of the different muscle movements in the area. A fracture line that runs downward and forward from the molar area has less displacement than does a line that runs downward and backward. The muscle groups that operate the mandible include the anterior (depressor-retractor) group and the posterior (elevator) group. The anterior muscle group displaces fragments in a downward, posterior, and medial direction, whereas the posterior group displaces fragments in an upward, forward, and medial direction. Consequently, a fracture through the angle of the mandible in a downward and backward direction has a far greater displacement because of the distracting forces of the posterior muscle group. However, if the fracture line is in the downward and forward direction, the muscle pull of the posterior group tends to keep the fracture segments in an anatomic position. Third, the presence or absence of teeth influences displacement of the fractures. Teeth on the proximal segment may decrease the displacement of the fractures by meeting the corresponding teeth of the maxilla. Finally, the presence and extent of soft tissue wounds result in a larger displacement with larger defects.

Clinically, the principal physical abnormality will be varying degrees of malocclusion. The patient may simply state, “My teeth don’t feel right,” or physical examination may demonstrate gross malocclusion. Anesthesia of the lower lip is common in fractures of the body of the mandible. Edema and ecchymosis may mask mandibular asymmetry. On examination, tenderness to palpation over the fracture site and pain with movement are observed. Crepitation may be noted with motion. Oral excursion is decreased. However, the principal physical abnormality is malocclusion.

Although the clinical examination most frequently establishes the diagnosis of mandibular fractures, roentgenographic studies more clearly define the direction of the fracture line, the relationship of the teeth to the fracture, and the degree of displacement. Posteroanterior and oblique lateral views of the mandible demonstrate fractures of the body and the angle without difficulty. If available, a Panorex view of the mandible is an excellent and necessary study that shows fractures at any site. Fractures of the temporomandibular joint and condylar area are sometimes difficult to demonstrate on routine mandibular roentgenograms, however, and may require tomograms for the final diagnosis (Fig. 17-6).

Fig. 17-6 Tomograms of the condylar process are sometimes required to establish a fracture of the condylar neck (arrow).

The most common fracture of the mandible (36%) is in the neck of the condyle. The incidence of fractures in this site is closely followed by that of fractures in the angle of the mandible (20%), the body (21%), and the area of the symphysis (14%). Other sites are much less commonly involved.

The principles of treatment for mandibular fracture include early anatomic reduction of the fracture, immobilization, and control of infection. An isolated mandibular fracture should be reduced at the time of injury. However, if other life-threatening injuries are present, treatment of the mandibular injury may be postponed for 7 to 10 days. All mandibular fractures are considered compound if the slightest displacement is present, and consequently, preoperative and postoperative antibiotics are recommended. Immobilization requires at least the application of arch bars and intermaxillary fixation (IMF) with rubber bands or wires for a minimum of 5 weeks. Rigid fixation with plates or screws is an option. Because IMF is not usually required after rigid stabilization, patients are able to begin a soft diet almost immediately after open reduction. Consequently, the weight loss and compromised oral hygiene present in patients with IMF are markedly reduced. The use of compression plates has also made the treatment of edentulous patients with mandible fractures much simpler.

Early complications of mandibular fracture may include infection, avascular necrosis, osteitis, and osteomyelitis. Predisposing factors to infection are poor oral hygiene, multiple caries, or a compound fracture. Diabetic patients are more susceptible to infections. Acute infection manifests as an abscess and is reflected by pain, swelling, and erythema in the area of the abscess. Incision, drainage, and systemic antibiotics constitute the treatment of choice. Chronic infections such as osteitis and osteomyelitis usually occur when a comminuted fracture with an avascular bone segment has occurred. Pain and roentgenographic changes suggestive of osteomyelitis are usually evident. Late complications may also include malocclusion or nonunion, and these require further corrective surgery.

Fractures of the Maxilla

Fractures of the maxilla, or midface, most commonly are caused by a high-velocity–type injury. Their incidence in recent years has decreased, primarily because of lower highway speed limits and increased use of seat belts. However, such injuries may occur in collisions at speeds as low as 30 miles per hour. The force necessary to cause fractures of the maxilla also increases the likelihood of severe injuries to other organ systems. Associated injuries of various degrees of severity more frequently involve the head but also occur in the chest and abdomen. Skeletal injuries may be present in approximately one third of the patients, whereas blindness is observed in one tenth. Additionally, the frequency of cervical spine injury is much higher with this injury than with other types of facial fractures.

Maxillary fractures can be divided into two groups: vertical and horizontal. Vertical fractures split the palate on either side of the septum. However, the three classic fractures of the maxilla are those horizontal defects described by Le Fort (Fig. 17-7). The Le Fort I (transverse) fracture is a horizontal fracture immediately above the level of the teeth. The Le Fort II fracture has the configuration of a pyramid, with the apex being across the nasal bridge. It extends through the nasal bones, the frontal processes of the maxilla, the lacrimal bones, the inferior rim and floor of both orbits, and the maxillozygomatic suture line. From this last point, the fracture continues posteriorly through the lateral wall of the maxilla and the pterygoid plates into the pterygoid maxillary fossa. The Le Fort III fracture separates the craniofacial complex and extends through the zygomaticofrontal, maxillofrontal, and nasofrontal suture lines, the floors of the orbit, and the ethmoid and sphenoid bones (Fig. 17-8).

Fig. 17-7 Le Fort fracture lines.

Fig. 17-8 A Le Fort III craniofacial separation (arrows) is evident in a Waters’ view of an 8-year-old patient. The opacity of the left maxillary sinus is more severe than the right.

Clinically, the patient may be comatose and may require immediate neurosurgical consultation. If conscious, there may be complaints of the inability to “match” the teeth properly. Infraorbital nerve numbness may be present. In Le Fort II or III fractures, nasal hemorrhage is usually evident. On physical examination, facial deformities may be masked by edema and ecchymosis. Bimanual palpation along the orbital ridges may detect steplike deformities or separations and tenderness. Forward movement of the maxilla is elicited with all three types of Le Fort fractures; in the Le Fort III fracture, the entire midthird of the face may move. However, occasionally these fractures may be impacted, and no movement will be evident. Malocclusion can be an initial sign and should suggest a maxillary fracture if the mandible is intact. Extraocular muscle dysfunction may be manifested by diplopia with superior gaze. Blindness is uncommon but may occur.

With extension of the maxillary fractures into the cribriform plate, rhinorrhea mixed with blood is detected as a result of the dural defect. The patient may note a salty taste in the back of the mouth. Any clear fluid from the nose should be tested for glucose. Glucose levels greater than 30 mg/100 mL confirm the presence of cerebrospinal fluid (CSF) and a tear in the dura. In this case, the patient’s nose should not be packed, despite the possible presence of depressed nasal fractures, and the patient should be instructed not to blow his or her nose. Prophylactic antibiotics that cross the blood–brain barrier should be instituted to decrease the possibility of the development of a retrograde infection. When meningitis has occurred in this type of injury, the most common organism isolated has been Pneumococcus, sensitive to penicillin.

Roentgenographically, the Waters’ view is the most reliable in demonstrating maxillary fractures in the emergency department. For vertical or alveolar fractures, occlusal views are more suitable. CT scans of the facial bones more accurately detail the full extent of the fractures. The study is usually done in the coronal view and shows the amount of the comminution, the degree of rotation, and the extent of displacement of the fracture segments (Figs. 17-9 and 17-10). Additionally, injury to the optic nerve or fat herniation may be visible.

Fig. 17-9 Coronal CT scan of multiple facial fractures shows obvious injuries to the nasoethmoid complex, horizontal maxilla (Le Fort I) and orbital rims.

Fig. 17-10

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