Upper jaw damage in peacetime and in extreme conditions: damage anatomy, classification, clinic course, medical help for wounded on the medical evacuation. Hand treatment of the surgeon when upper jaw damaged, principles of plastic surgery.
The results of epidemiologic surveys on maxillary fractures differ with the politics and population density of the geographic region studied, the era in which the surveys were performed, the socioeconomic status of the population, and the institution whose experience was reviewed.1–5 It is difficult to make generalized statements about the findings of these studies, but trends do exist, and these trends make it clear that maxillary fractures are more frequently associated with motor vehicle accidents and motorcycle accidents than with any other cause. Maxillary fractures most often occur in conjunction with other facial fractures and are most often associated with injuries such as lacerations, other facial fractures, orthopedic injury, and neurologic injury.1,2,5,6 Most maxillary fractures occur in young men aged 16 to 40 years; they are most common among patients between 21 and 25 years of age, and the risk of sustaining facial bone fractures increases as the age of the patient increases.6 History Although maxillary fractures are commonly classified according to the Le Fort system, these fractures were described and treated thousands of years before Rene Le Fort was born. The first clinical examination of a maxillary fracture was recorded in 2500 BC in the Smith Papyrus.7 Many other early records describe treatments for maxillary fractures or the iatrogenic fracture of the maxilla for therapeutic purposes. In 1822 Charles Fredrick William Reiche provided the first detailed treatise of maxillary fractures, entitled De Maxillae Superiors Fractura.7 In 1823 Carl Ferdinand van Graefe described the use of a head frame for treating a maxillary fracture.7 His device was as technically complex as those currently in use. In 1859 Bernhard R. K. Von Langenbeck described a technique for the osteoplastic resection of the maxilla.8 In 1867 David Cheever discussed complete mobilization of the maxilla with the use of chisels for the removal of a nasopharyngeal tumor.9 In 1893 Otto Lanz also described the creation of an iatrogenic maxillary fracture for access to a tumor. It was not until 1901 that Rene Le Fort published his landmark works, a three-part experiment using 32 cadavers that were either intact or decapitated.10–12 The heads of the cadavers were subjected to various types of trauma; the soft tissue was then removed and the bones were examined. Le Fort noted that, generally, if the face was fractured, the skull was not. He then stated that fractures occurred through three weak lines in the facial bony structure: those that protect the cranial cavity, those that circumscribe the midface, and those that cut across the face. From these three lines the Le Fort classification system was developed (Figure 23.1-1). Le Fort Classification System In his description of maxillary fractures Le Fort considered several factors: the vector
of force overcoming the inertia of the face; the thickness of the bone and buttresses counteracting the mass, velocity, and point of application; and the maxilla, which he noticed was unaffected by muscle pull, unlike the long bones. These considerations resulted in a classification of three levels of fracture.
Le Fort I Level
Maxillary fractures at the Le Fort I level traverse the lateral antral wall, the lateral nasal wall, and the lower third of the septum, and they separate at the pterygoid plates. Thus, the entire mobilized segment consists of the maxillary alveolar bone, the palatine bone, the lower third of the nasal septum, and the lower third of the pterygoid plates. The superior two-thirds of these bones remain associated with the face.
Le Fort II Level
Maxillary fractures at the Le Fort II level involve most of the nasal bones, the maxillary bones, the palatine bones, the lower two-thirds of the nasal septum, the dentoalveolus, and the pterygoid plates. Unlike the horizontal separation noted in the Le Fort I fracture, the Le Fort II fracture is pyramidal in shape. The fracture extends from below the nasofrontal suture through the nasal bones along the maxilla to the zygomaticomaxillary suture and includes the medial inferior third of the orbit. The fracture then continues along the zygomaticomaxillary suture to and through the pterygoid plates. The septum is also separated superiorly. The segments may be intact below this line of fracture, but they are most often comminuted.
Le Fort III Level
Fractures at the Le Fort III level involve the nasal bones, the zygomas, the maxillae, the palatine bones, and the pterygoid plates. These fractures essentially separate the face along the base of the skull. The fracture line extends from the nasofrontal suture along the medial wall of the orbit through the superior orbital fissure. It then extends along the inferior orbital fissure and the lateral orbital wall to the zygomaticofrontal suture. The zygomaticotemporal suture is also separated. The fracture then extends along the sphenoid bone, separating the pterygoid plates. The septum becomes separated at the cribriform plate of the ethmoid. Le Fort III fractures are most often comminuted. With highly comminuted fractures, patients may sustain fractures at more than one level. Virtually all combinations of Le Fort I, II, and III fractures are possible on either side of the face. In Garretson’s 1898 treatise the primary method of treating fractures of the maxillae was to construct a bandage or dressing that elevated the mandible into occlusion and secure it there.13 A number of materials were used to add stability to these bandages, including plaster of Paris, wood, gutta-percha, and vulcanized rubber. In addition to splinting the jaws Garretson advocated the use of interdental splints, stating “As a means of dressing in any complicated jaw fracture, the interdental splint is as invaluable and reliable as it is simple of construction and easy of application.”13 Blair gave a very good description of the anatomy of maxillary fractures and of the examination for diagnosing such fractures. 14 He noted that mandibular bandages were insufficient to stabilize maxillary fractures and advocated a maxillary splint, quoting an authority of the day, Dr. John L.Marshall: Impressions of the upper and lower teeth were taken with the modeling compound by first molding it upon the upper teeth and while it was yet soft forcing the lower jaw upward until a correct occlusion of the teeth was obtained. This impression was trimmed to the desired shape; a one-eighth-inch steel wire was imbedded in the sides on a line with the ends of the teeth, then bent backward upon itself opposite the cuspid teeth. . . .
From this was constructed a hard-rubber splint, with the wires attached. . . . The splint is held in position by means of double elastic straps attached to the wire on each side and buckled to a close-fitting leather or net cap, which is reinforced with leather and laced firmly on the head. . . . The object of [the splint] was to furnish a sure guide to the normal position of the superior maxillae. Without this the correctness of the adjustment of the bones could not have been verified. Its importance therefore cannot be overestimated.14 Similar treatment modalities were presented by Brophy in 1918; he presented illustrations of the splints as well as preoperative and postoperative images of a patient.15 Anatomy
The two maxillae are paired structures connected by a midline suture; the bones together compose a five-sided pyramid. The anterior surface slopes downward from its superior contact with the frontal and nasal bones at an angle of approximately 15°. The most prominent point at the anterior surface is the anterior nasal spine. A number of protuberances exist on the maxilla, formed by the alveolar base and origins of the small facial muscles. The lateral surface of the maxillae forms the infratemporal fossae and buccal vestibule and attaches to the zygoma.Most of the superior surface forms the majority of the orbital floor. The medial surface of each maxilla forms the midline suture and lateral nasal walls. This includes the nasal concha and sinus ostia. The ostium of the nasolacrimal duct is beneath the inferior concha. The ostia of the maxillary sinus and middle ethmoids, as well as the opening of the nasofrontal duct, lie beneath the middle concha.
The inferior border composes the palatal vault and alveolus, which contain the teeth. The posterior border abuts the sphenoid bone and the pterygomaxillary suture.16 Within the maxilla is the maxillary sinus. This 34 . 33 . 25 mm air cavity is responsible for the weakness of the maxilla. The sinus is present at birth but does not pneumatize to its mature extent until the patient reaches 14 to 15 years of age. Minor changes in the sinus continue throughout life.17 The strong buttresses of the maxilla are the lateral piriform buttress, the zygomatic buttress, the greater palatine buttress, and the floor of the nose. The palatine bone is L shaped and abuts the posterior maxilla as a paired structure. These bones assist the maxilla in forming the posterior sinus, the posterior lateral nasal wall, and the pterygomaxillary suture.When joined to the maxilla the four bones represent one unit (Figure 23.1-2).16 The nasal bones are paired structures that abut the frontal bone superiorly, the maxilla laterally, the septum posteriorly and medially, and each other anteriorly and medially. The bones are thicker superiorly; therefore, fractures at the Le Fort II level may occur inferior to the nasofrontal suture. The nasal septum is a thin trapezoidal bone lying perpendicular to and joining the maxillae and palatine bones.
The superior border is thick and articulates with the ethmoid bone.16 The ethmoid bone is cuboidal and extremely pneumatized; thus, it can be easily fractured and comminuted. The cribriform plate of the ethmoid composes the roof of the nasal cavity and communicates with the anterior cranial fossae through multiple foramina for the olfactory nerves. Lateral to the crista galli is a slit through which dura mater is exposed. Posterior and superior movements of the midface can easily comminute this bone, thus disrupting the dura mater and resulting in a cerebrospinal fluid leak.16 The zygoma abuts the frontal bone at the frontozygomatic suture and the temporal bone at the zygomaticotemporal suture. The maxilla and zygoma form twothirds of the orbital rim and, along with the palatine bone, one-third of the walls and floor of the orbit. The infraorbital nerve traverses the orbital floor and exits through the infraorbital foramen. The maxillary bone, along with the zygoma, forms the inferior orbital fissure. Through this fissure run the maxillary nerve, the infraorbital vessels, and the ascending branches of the pterygopalatine ganglion. The frontal process of the maxilla contains the lacrimal apparatus, which is housed between the medial canthal ligaments. The blood supply to the maxillae and palatine bones is through the periosteum, the incisive artery, and the greater and lesser palatine arteries. The internal maxillary artery, a source of potentially devastating hemorrhage, lies posterior to the maxillae and palatine bones and anterior to the pterygoid plates of the sphenoid.18 The blood supply to the nasal septum and the lateral nasal walls is provided by the anterior and posterior ethmoidal arteries, the sphenopalatine artery, and the greater palatine and superior labial arteries.16
Diagnosis Clinical Examination
Advanced trauma life-support protocols should be followed for all patients who have suffered trauma. Detailed examination of maxillofacial fractures is completed in the secondary survey, after the primary survey and successful resuscitation have been completed. As has been done historically the clinical examination should begin with the initial observation of the patient, followed by palpation of the fractures.14,19 As was written by Blair in 1914, “…In all cases of injury of the face the dental arches and the palate should be inspected, and the facial bones outlined digitally.”14 Lacerations, abrasions, and ecchymotic areas should be recorded. Periorbital ecchymosis and facial edema should be noted and are very typical of these fractures. Epistaxis with any evidence of cerebrospinal fluid leakage (clear fluid mixed with blood, “tram lines”) should be identified. Asymmetry of the nose, traumatic telecanthus, a flat nasal bridge, and a dish-shaped face should all be noted. Intraorally the examiner may see fractured teeth, vestibular ecchymosis and edema, palatal ecchymosis, mucosal
lacerations and bleeding, steps or diastema in the maxillary teeth, and malocclusion. The skeletal framework of the face should be carefully palpated.With respect to the maxilla, the alveolus should be palpated and any fractures or mobility noted. The examiner should also observe the maxilla for movement as a unit, while palpating the forehead, the nasal bridge, and the zygomaticofrontal sutures. The nose should be examined grossly for contour irregularity (Figure 23.1-3). A nasal speculum should be used to identify compound fractures of the septum or septal hematoma. Both hands should be used to palpate the orbital rims and in particular the zygomaticomaxillary suture. The intraoral examination should be complete, and the examiner should note accumulation of blood, debris, or avulsed teeth that could compromise the airway, as well as the presence of laceration, abrasion, or ecchymosis. Abnormal occlusion with an anterior open bite and posterior prematurities should be noted and correlated with pretraumatic occlusion if possible (family members, photographs, dental records).
Imaging
Fractures are identified clinically and confirmed radiographically. In the past the Waters’ view and lateral facial radiographs were used in identifying maxillary fractures and may still be used today in remote areas without access to a computed tomography (CT) scanner (Figure 23.1-4). Fine details of the fracture sites are difficult to visualize. Axial and coronal CT scans of the midface should be obtained if a scanner is available (Figure 23.1-5). If clinical evidence strongly indicates maxillary fracture (midface mobility and malocclusion with intact mandible), then CT imaging is a confirmatory test for maxillary fractures. Important indications for CT scanning are suspected orbital floor fractures (best diagnosed in the coronal view) and surgical planning. CT scans can also demonstrate the soft tissue differences of hematoma or edema of the subcutaneous tissue, muscle, and fat. For severe midface trauma or maxillary displacement, the three-dimensional CT scan is a valuable tool (Figure 23.1-6).
Treatment
Patients do not die of maxillary fractures, but they may die of concomitant injury or failure to manage the sequelae of maxillary fractures. As is true for all injuries initial attention should be directed at establishing an airway and controlling hemorrhage. The most frequent cause of hemorrhage in Le Fort level fractures is a fractured septum. This bleeding may be addressed by placing nasal packs of one of a number of materials, including gauze packing, Merocel packing (Medtronic Xomed), Rhinorocket (Shippert Medical Technologies Corp.), and Epistat (Medtronic Xomed). Bleeding from sites of laceration or abrasion may be controlled by tamponade. Exsanguinating hemorrhage is rarely encountered with facial fractures; however, its occasional occurrence has long been noted: “Hemorrhage, which is not readily amenable to successful treatment, as in the case of rupture of the internal maxillary artery or its terminal branches, may be followed by fatal results.”15 Should uncontrollable bleeding be encountered, the patient should undergo angiographic evaluation with embolization of the injured artery if indicated.20–24 At least one group has suggested caution in the use of embolization because of the possible crossover of the embolic material between the external and internal carotid circulation.25 Maxillary fractures isolated to the dentoalveolar process and involving bone should be manually reduced and rigidly fixated with arch bars and ligature wires. If the segment is too large to be stabilized with arch bars alone, acrylic can be added to the facial surface of the arch bar, or an occlusal splint can be constructed and secured in place. Complications include bone resorption, ankylosis of teeth, external root resorption, and tooth loss.26,27 In more extensive injuries the sequence of treatment of maxillary fractures depends largely on the associated injuries. Nasotracheal intubation is preferred when it is not contraindicated by the need for complicated repair of nasal and nasoethmoidal injuries. In such cases a submental intubation technique can be used28–32; tracheotomy is a final option (Figure 23.1-7).
After the airway has been secured and general anesthesia has been administered, arch bars should be placed, along with any required splints or stents. If teeth are deemed unsalvageable they should be removed at this time. The sequence of treatment depends on the surgeon’s philosophy and the presence of other facial fractures.Whether the surgeon prefers to work from the “bottom up” or from the “outside in,” anterior projection of the maxilla is most easily obtained when the mandible is intact. For this reason strong consideration should be given to the repair of any mandible fracture before the maxilla is stabilized. Intermaxillary fixation (to an intact mandible) is the most reliable technique for establishing anterior projection of the maxilla (Figure 23.1-8). Although many wiring techniques have been described in the past, rigid internal fixation is the standard of care.19,33–36 The maxilla should be stabilized to the next highest stable facial structure, which varies with Le Fort fracture level. At the Le Fort I level, fixation is placed along the vertical buttresses of the maxilla at the piriform and zygomatic buttresses. At higher Le Fort levels it may be necessary to use fixation to the nasal bones, the orbital rims, or the zygomaticofrontal sutures. Although Le Fort levels are frequently referred to in discussions of patient treatment, high-quality CT scans and widespread use of rigid fixation have led to the treatment of multiple facial fractures as separate units. For example, a Le Fort I/II fracture would be treated as a Le Fort I fracture, a left orbital fracture, or a left zygomaticomaxillary complex fracture. In these cases it is advisable to restore midface projection with the repair of orbital or zygomatic fractures before fixation of the maxilla. Contemporary bone plates and screws are made of titanium. For maxillary reconstruction these plates must be of sufficient rigidity to overcome the effects of gravity; the forces of mastication are resisted by bone contact. For this purpose screws with an outer diameter of 1.5 mm are adequate. In areas such as the orbital rim or nasal bone, 1.3 mm or 1.0 mm systems may be used. In cases in which bone contact is decreased because of comminution, 1.7 mm or 2.0 mm systems may be used. If resistance is encountered during mobilization of the maxilla,
Rowe disimpaction forceps may be used to help reduce the fracture (Figure 23.1-9). The paired forceps are placed with the fat end in the nose and the bowed end on the palate. The surgeon stands over the patient’s head and in an inferior-anterior movement disimpacts the maxilla. Further assistance may be provided with Hayton– Williams forceps used in conjunction with the Rowe disimpaction forceps. If the maxillary fracture is incomplete (eg, greenstick fracture), the surgeon may have difficulty in mobilizing the maxilla. The fractured hemimaxilla may be impacted or telescoped, causing severe malocclusion with minimal mobility. In a case such as this, severe difficulty with disimpaction of Le Fort level fractures can be easily overcome by completing the fracture with an osteotomy. This concept is not as novel as it might sound; in 1914, Blair wrote, “…if the impaction cannot be broken up . . . resort may be had to a small, sharp chisel.”14 After down-fracture the maxilla can easily be moved into appropriate occlusion and stabilized without further difficulty (Figure 23.1-10). Immediate bone grafting has been advocated for the severely comminuted maxillary antrum.37 This treatment prevents prolapse of the facial soft tissue into the maxillary sinus and the facial deformation that results. Titanium mesh works well for this procedure; it is malleable, can be quickly fixated, resists pressure of the soft tissues of the face, becomes osseointegrated, and allows regrowth of the native tissue (ie, ciliated respiratory epithelium, goblet cells, squamous epithelium) (Figure 23.1-11).38
Soft Tissue Injuries
In the
Principles of Management
The initial examination involves evaluating and stabilizing the trauma patient. Any life-threatening conditions should be identified and managed immediately. The conditions of the airway, breathing, and circulation are examined, followed by a general neurologic assessment with particular attention to cervical spine and cranial injuries. It is important to achieve hemostasis when stabilizing and evaluating the patient who has sustained trauma. Most bleeding will respond to application of a pressure dressing. Occasionally surgical exploration and packing of the wound under general anesthesia may be indicated. In rare instances vessels in the neck may need to be ligated. Indiscriminate clamping inside the wound should be avoided because damage to important structures such as the facial nerve or parotid duct may result. It is unusual for bleeding from soft tissue injuries to the face to result in a shock state. Lacerations involving the scalp can occasionally be difficult to control with pressure and may require clamping, ligation, or electrocautery. In soft tissue injuries not involving the face the length of time from initial injury to treatment is important. Secondary risk of infection increases with the lapse of time.3 Because of the rich vascularity of the face there is no “golden period” for suture repair of facial wounds. In fact healing of facial wounds is unaffected by the interval between injury and repair.4 Patients who are immunized and have received a booster injection within the last 10 years do not require tetanus prophylaxis if the wound is not tetanus prone. Tetanus-prone wounds are those with heavy contamination from soil or manure, devitalized tissue, or deep puncture wounds. If the wound is tetanus prone and the patient has not received a booster injection within 5 years prior to the injury, a 0.5 mL tetanus toxoid boost injection should be given. If the patient has not received a booster within 10 years prior, they should receive a booster injection for any wound. Patients who are not immunized should receive both a booster injection and 250 units of tetanus immunoglobulin, followed by a full course of immunization.5 Treatment of soft tissue injuries involves early reconstructive procedures addressing both the soft tissue and the underlying bony injury in a minimum number of stages.6,7 Occasionally it is better to delay soft tissue repair until the facial fractures have been addressed. In patients with large avulsion of tissue, definitive early reconstruction of the tissue loss with regional or microvascular flaps may be required.
Anatomic Evaluation
Following the initial evaluation and resuscitation, injuries to the soft tissues should be evaluated during the secondary survey. Patients sustaining trauma often have associated soft tissue injuries. Facial injuries can be superficial but may extend to involve adjacent structures including bones, nerves, ducts, muscles, vessels, glands, and/or dentoalveolar structures. Associated injuries, including vascular injury, may develop acutely or days after the injury.10,11 A thorough head and neck examination determines the extent of associated facial wounds. Peripheral cranial nerves are commonly involved with lacerations that involve the face. The facial nerve divides the parotid gland into deep and superficial portions (Figure 19-1). Any injury to the gland should raise suspicion for associated facial nerve injury.12 The facial nerve exits the stylomastoid foramen and divides intofive branches within the parotid gland (Figure 19-2). Proximal facial nerve injuries posterior to a vertical line drawn from the lateral canthus should be repaired using microsurgical techniques. Because of the significant peripheral anastomoses, repair of facial nerve injuries involving distal branches anterior to the canthal plane is unnecessary (Figure 19-3). Injury to the parotid gland can lead to leakage of saliva into the soft tissue. The parotid duct is approximately 5 cm in length and 5 mm in diameter. It exits the gland and runs along the superficial surface of the masseter muscle and then penetrates the buccinator muscle to enter the oral cavity opposite the upper second molar. Treatment of parotid duct injuries depends on the location of the injury. These injures should be repaired in the operating room with the aid of magnification. If the injury involves the proximal duct while it is still in the gland, the parotid capsule should be closed and a pressure dressing placed. If the injury is located in the midregion of the duct, the duct should be repaired. Injuries involving the terminal portion of the duct should be drained directly into the mouth. Lacrimal probes are useful in cannulating the duct and identifying injuries
.
A polymeric silicone (Silastic) catheter is placed to bridge the defect.The severed ends are then sutured over the catheter, which is left in place for 10 to 14 days (Figure 19-4). The parotid capsule should be closed to prevent formation of a parotid duct fistula or sialocele. Lacerations are closed primarily and a pressure dressing is placed to prevent fluid accumulation. There are several protocols for evaluation and treatment of penetrating injuries to the neck, face, and temporal bone. If there is suspicion that deep critical structures have been injured, the appropriate protocol should be followed.
Sequence of Repair and Basic Technique
A decision is made to repair the wound in the emergency department or to perform the repair in the operating room under a general anesthetic. Large complicated lacerations demand ideal lighting and patient cooperation. In injuries where there is a concern that deep structures have been damaged, a general anesthetic affords the best opportunity for exploration and repair. The patient may require repair of other traumatic injuries in the operating room, and on many occasions, definitive repair of associated facial soft tissue injuries can be performed at the same time. Lidocaine is a popular local anesthetic and ranges in strength from 0.5 to 2%. It is usually administered with epinephrine 1:100,000. Lidocaine has a rapid onset of action, a wide margin of safety, and a low incidence of allergic sensitivity. A thorough evaluation of the seventh cranial nerve should be undertaken prior to injection of anesthetic or administration of a general anesthetic. Injecting local anesthetic prior to cleaning the wound will allow more effective preparation. Local anesthetics containing epinephrine have been used successfully in all areas of the face but may not be optimal in areas where tissue monitoring is critical or where extensive undermining of the soft tissue is necessary.13 One should avoid injecting directly into the wound when important landmarks could be distorted. Regional nerve blocks are beneficial in minimizing the amount of local anesthesia required and also prevent distortion of the tissues.14 After adequate anesthesia has been obtained, the wound is thoroughly debrided. Nonvital tissue is conservatively excised in an attempt to salvage most of the tissue. Devitalized tissue potentiates infection, which inhibits phagocytosis. Persistent infection at a wound site leads to the release of inflammatory cytokines from monocytes and macrophages, which delays wound healing. An anaerobic environment results and limits leukocyte function.15 Soft tissue wounds are often contaminated with bacteria and foreign material. Treatment of these injuries involves copious irrigation and is aimed at minimizing the bacterial wound flora and removing any foreign bodies. With respect to infection rates, studies have showo statistical difference in wounds irrigated with normal saline when compared to other solutions. Pulsatile-type irrigation devices may be helpful to remove debris, necrotic tissue, and loose material. Hydrogen peroxide impedes wound healing and has poor bactericidal activity. A good rule is to avoid irrigating the wound with any solution that would not be suitable for irrigating the eye. Careful and meticulous cleaning of the wounds primarily will avoid unfavorable results such as “tattooing,” infection, hypertrophic scarring, and granulomas. A scrub brush and detergent soap may be necessary to remove deeply imbedded foreign material. However, soaps may cause cellular damage and necrosis. A surgical blade may be helpful to scrape foreign material that is deeply embedded. Polymyxin B sulfate can be used to remove residual grease or tar in wounds. Proper cleaning and good surgical technique are imperative in minimizing infection. Infections are rare when the wound is closed so that no dead space, devitalized tissue, or foreign bodies remain beneath the sutured skin. Hydrogen peroxide is minimally bactericidal and toxic to fibroblasts even when diluted to 1:100.16 Diluted hydrogen peroxide is useful in the postoperative period in cleaning crusts away from incision lines in order to minimize scarring. Common methods for closing wounds include suturing, applying adhesives, and stapling. It is preferable to suture complex facial lacerations secondary to esthetic considerations. A layered closure is almost always necessary and eliminates dead space beneath the wound. If the dead space is not obliterated, accumulation of inflammatory exudates may occur. This leads to infection, which in turn may cause tension across the epidermis. Tension can cause necrosis of the skin edges due to impairment of the vascular supply and may cause an increase in scarring.17 Injuries involving anatomic borders such as the vermilion of the lip must be reapproximated precisely. Examples of these landmarks include eyebrows, lip margins, and eyelids. Lacerations should be closed by placing a suture in the center of the laceration to avoid creating excessive tissue on the end of the laceration (dog-ear). Deep layers should be reapproximated with 3-0 or 4-0 buried resorbable sutures. The superficial skin is closed with 5-0 or 6-0 suture. It is important to avoid causing puncture marks when grasping the wound edges. Margins should be undermined to allow slight eversion of the wound margin. Skin sutures should be removed 4 to 6 days after placement. By this time the wound has regained only 3 to 7% of its tensile strength and adhesive strips help support the wound margins.18 At 7 to 10 days following suture removal the collagen has begun to crosslink. The wound is now able to tolerate early controlled motion with little risk of disruption (Figure 19-5).19 As the wound heals it will contract along its length and width and become inverted due to collagen and fibroblast maturation. Initial management is aimed at producing a slightly everted wound edge. The wound continues to remodel up to a year following injury but never regains greater than 80% of the strength of intact skin. Tissue adhesives are gaining in popularity. Some studies have suggested similar cosmetic outcomes in wounds treated with octylcyanoacrylate when compared to standard wound closure techniques for non–crush-induced lacerations treated less than 6 hours after injury.20–22 Closure of lacerations with octylcyanoacrylate is faster than standard wound closure methods. However, its use should be avoided in complex lacerations involving the face, where there are esthetic concerns. Suture materials and different surgical techniques do not show substantial differences in relation to outcome. General characteristics of the patient (ie, sex and age) and of the wound (ie, length and site) seem to be important predictors of adverse tissue reaction.23,24 Suboptimal appearance is associated with wounds that are infected, wide, incompletely approximated, or have sustained a crush injury. The total number of bacteria is more important that the species of bacteria contaminating a wound. Greater than 105 aerobic organisms per gram of tissue are needed for contamination, and crush-type wounds are 100 times more susceptible to infection.25 Delayed primary closure may be necessary in some instances. Patients who may benefit from a delayed procedure include those with extensive facial edema, a subcutaneous hematoma, or those with wounds that are severely contused and contain devitalized tissue. Secondary revision procedures are usually undertaken months later to allow for scar maturation. Clinical examination and radiographs are used to diagnose fractures of the face. Facial fractures are ideally treated prior to soft tissue repair. If repair of the facial bones is delayed, it is optimal to close the lacerations initially. The wounds can be reentered and revised if needed to access the fracture site.
Types of Injuries
Abrasions
Shear forces that remove a superficial layer of skin cause abrasions. The wound should be gently cleansed with a mild soap solution and irrigated with normal saline. These superficial injuries usually heal with local wound care. It is important to determine whether foreign bodies have been embedded in the wound. Failure to remove all foreign material can lead to permanent “tattooing” of the soft tissue. After the wound is cleansed the abrasion is covered with a thin layer of topical antibiotic ointment to minimize desiccation and secondary crusting of the wound. Reepithelialization without significant scarring is complete in 7 to 10 days if the epidermal pegs have not been completely removed. If the laceration significantly extends into the reticular dermal layer, significant scarring is likely.
Contusions
Contusions are caused by blunt trauma that causes edema and hematoma formation in the subcutaneous tissues. The associated soft tissue swelling and ecchymosis can be extensive. Small hematomas usually resolve without treatment; hypopigmentation or hyperpigmentation of the involved tissue can occur, but is rarely permanent. Large hematomas should be drained to prevent permanent pigmentary changes and secondary subcutaneous atrophy.
Lacerations
Lacerations are caused by sharp injuries to the soft tissue (Figure 19-6). Lacerations can have sharp, contused, ragged, or stellate margins. The depth of penetration should be carefully explored in the acute setting. Closure is performed using a layered technique. If the margins are beveled or ragged they should be conservatively excised to provide perpendicular skin edges to prevent excessive scar formation. Rarely is there an indication for changing the direction of the wound margins by Zplasty at the time of primary wound repair. Flap-like lacerations occur when a component of the soft tissue has been elevated secondary to trauma. Eliminating dead space by layered closure and pressure dressings is especially important in these “trapdoor” injuries.
Avulsive Injures
Avulsive injures are characterized by the loss of segments of soft tissue. Undermining the adjacent tissue, followed by primary closure, can close small areas.When primary closure is not possible, other options are considered. These include local flaps or allowing the wound to heal by secondary intention followed by delayed soft tissue techniques. If a significant amount of soft tissue is missing, then a skin graft, local flaps, or free-tissue transfer may be necessary (Figure 19-7).
Animal and Human Bites Dog bites are most common in children and the midface is frequently involved.26,27 Canines can generate 200 to 450 psi when biting, and examination for fractures should be performed.28 Management of bite injuries involves liberal amounts of irrigation and meticulous primary closure.29 Wound irrigation and debridement are important in reducing infection. Animal and human bites are most often polymicrobial, containing aerobic and anaerobic organisms. Dog bites are often open and lend themselves to vigorous irrigation and debridement. Cats have a large quantity of bacteria in their mouth, with the most frequent and important pathogen being Pasteurella multocida.30 Cat bites are associated with a twofold higher risk of infection than the more common dog bite wounds. Because their bites usually cause puncture wounds, they are difficult to clean. Having the patient follow up 24 to 48 hours after the initiation of therapy allows the surgeon to monitor the wound for any signs of infection. Antibiotic prophylaxis for animal bites continues to be debated with few good prospective studies available.26,31 Amoxicillinclavulanate is the current drug of choice for bite wounds. Antibiotic prophylaxis should be directed at Pasteurella multocida for infections presenting within 24 hours of injury. For wounds that present after 24 hours of injury, Streptococcus and Staphylococcus species are more common, and antibiotic prophylaxis with a penicillinase-resistant antibiotic should be chosen.32 Immediate closure of bite injuries is safe, even with old injuries.33 There is approximately a 6% rate of infection when bite wounds are sutured primarily in lacerations where there are cosmetic concerns.34 Extensive animal bite wounds involving the face should be treated according to the criteria of esthetic reconstructive surgery. Rabies prophylaxis should be given for bite wounds that occurred from an unprovoked domestic dog or cat that exhibits bizarre behavior or from an attack by a wild animal such as a raccoon, skunk, bat, fox, or coyote.
Scalp and Forehead
Scalp wounds can occasionally cause a large amount of blood loss due to the rich vascular supply in this region and the inelasticity of the scalp preventing contraction and closure of the vessels. The layers of the scalp (SCALP) include the skin, subcutaneous tissue, aponeurosis layer, loose subepicranial space, and pericranial layer. In patients sustaining scalp injuries it is important to evaluate for associated intracranial injuries. Careful inspection should be performed to look for evidence of skull fractures. Because the scalp has an excellent blood supply in the subcutaneous tissues as well as the pericranial layers, avulsed tissue, skin grafts, and various flaps have a high rate of survival. Hollander and colleagues found no significant difference in rate of infection in scalp lacerations that were irrigated compared to those that were not.37 In avulsive defects in which the pericranium is intact and primary closure is not possible, a split-thickness skin graft can be used. A secondary reconstructive procedure involving various rotational and advancement flaps or tissue expansion can be undertaken after healing of the defect.38 If the cranial bone is exposed with large avulsive defects, then various flap procedures are indicated primarily. Reconstruction of the eyebrow is difficult secondarily, and efforts to repair lacerations primarily without distortion are important. Eyebrows should never be shaved, as regrowth of the hair is unpredictable. Closure of lacerations should attempt to salvage as much tissue as possible. Care should be taken to avoid damage to the remaining hair follicles. Scars can be removed 6 to 12 months later with incisions made parallel to the hair follicles to avoid injury.
Eyelid and Nasolacrimal Apparatus
A thorough ophthalmologic examination is important to assess for injuries to the globe and to evaluate and document visual acuity. Closure of lacerations involving the eyelids is done in a layered fashion (Figure 19-9). Care should be taken to precisely reapproximate the eyelid margins and the tarsus (Figure 19-10). The conjunctiva and tarsus are closed with resorbable sutures with the knot buried to avoid irritating the cornea. The orbicular muscle is then closed followed by closure of the skin. Injuries involving the upper eyelid may include detachment of the levator aponeurosis and Muller’s muscle from the tarsal plate. The muscles should be identified and reattached to the tarsal plate in order to prevent ptosis and restore levator function. The lacrimal gland produces tears, which flow across the cornea and drain into canaliculi via the puncta of the upper and lower eyelid margins (Figure 19-11). From the canaliculi the tears enter the nasolacrimal duct and drain into the inferior meatus of the nose. Any lacerations that involve the medial third of the eyelid should be carefully inspected for damage to the canaliculus.39 Repair is accomplished by introducing a lacrimal duct probe into the puncta and into the wound (Figure 19-12). The ends of the lacerated duct are identified and approximated over a polymeric silicone tube (Crawford tube). The tube is left in place for 8 to 12 weeks. If only one canaliculus is intact and functioning, the patient most likely will have adequate drainage.40 If the patient exhibits chronic epiphora postoperatively, then a dacryocystorhinostomy is indicated. Avulsive injuries to the eyelids are treated with skin grafts and/or local flaps. Defects of up to 25% of the eyelid length can be closed primarily. Skin grafts harvested from the opposite eyelid provide excellent texture and color match.
Nose
The nose occupies a prominent position on the face and is often injured. Injuries of the internal nose should be evaluated using a nasal speculum. The septum should be evaluated for the presence of a hematoma, which appears as a bluish elevation of the mucosa. Hematomas involving the nasal septum should be evacuated with a small incision or needle aspiration. Nasal packing or polymeric silicone nasal splints can be placed to prevent recurrence of the hematomas and are removed in 7 to 10 days. A running 4-0 chromic gut mattress suture placed in and through the septum can prevent recurrence. Untreated hematomas can lead to infection and necrosis of the cartilage, which may cause collapse of the septum and a resultant “saddle nose.” There is an excellent blood supply to the nose. Lacerations of the external nose should be closed with 6-0 nonabsorbable sutures. Key sutures should be placed to reapproximate anatomic landmarks to ensure proper orientation, especially around the nasal rim. Bone, cartilage, and/or skin grafts may be required to reconstruct avulsive defects of the nose. Skin grafts harvested from the periauricular regions provide excellent color and texture match.41 Local flaps may be required to restore missing tissue (Figure 19-13).
Ear
Injuries involving the external ear should alert one to the possibility of other injuries. An otoscopic examination of the external auditory canal and tympanic membrane combined with a hearing assessment should be performed prior to treatment. Injuries to the auricle include ecchymosis, abrasion, laceration, hematoma, and partial or total avulsion. Hematomas involving the ear usually occur when the ear sustains a glancing blow. These should be drained with a needle or incision. An incision is often preferable to simple aspiration because there is less of a chance of reaccumulation of the hematoma.42 Evacuation of the hematoma prevents fibrosis and development of a “cauliflower ear” deformity. A bolster dressing should be placed to prevent recurrence of the hematoma. A stent can also be fabricated from polysiloxane impression material and kept in place for 7 days.43 The ear has a very good vascular supply and can maintain tissue on a small pedicle. Injuries involving the cartilage often do not require sutures. If sutures are required a minimal amount are used to avoid devitalizing the region of cartilage (Figure 19-14). Avulsive injuries of the ear can involve a portion of the ear or the entire ear (Figure 19-15). If the avulsed segment is 1 cm or less, it can be reattached and allowed to revascularize.
Lip
The lip anatomy involves a transition of mucosal tissue to skin. Scars that affect the orbicularis oris may result in functional difficulties. Nerve blocks are helpful in wounds involving the lip to prevent distortion caused from injecting directly into the wound. A single suture should be placed initially to reapproximate the vermilion border exactly. Deep tissues are closed in layers, followed by closure of the mucosa with 4-0 chromic and skin closure with 6-0 nylon suture. Avulsive defects of the lips require special attention. Up to one-fourth of the lip can be closed primarily with acceptable functional and esthetic results. Injuries that involve a greater amount of tissue loss can be reconstructed with a variety of flaps such as Abbe-Estlander or Karapandzic (Figure 19-18).
Postoperative Wound Care
Careful postoperative care and follow-up are important to optimize results. Wounds should be monitored closely to determine whether early intervention is indicated to minimize scar contracture or hypertrophic scarring. Local flaps and grafts may be indicated secondarily. Local injection of steroids provides an adjunct in the management of specific types of injuries. Facial scars continue to mature over a period of 12 to 18 months. A recent study found no difference in outcome of surgical scars treated with pulsed carbon dioxide laser when compared with dermabrasion.51 Keeping a wound clean and scab free allows for more rapid reepithelialization.52 Epithelial cells survive and migrate better in a moist environment. Antibiotic ointment can enhance this migration. It is not epithelialization that provides strength to the wound but rather the collagen fibers supporting the surface. Rebuilding of fibers takes time, and suturing a wound splints the skin together until new connective tissue is built. Cleaning daily with dilute hydrogen peroxide and dressing with antibiotic ointment is standard. Patients should avoid sun exposure for the first 6 months after the injury to prevent hyperpigmentation of the areas.
Summary
Soft tissue injuries involving the face can be devastating to the patient. Primary repair of these wounds is almost always advantageous over delayed secondary procedures. The primary goals of treatment are to restore patients to their preoperative state of function and to achieve an esthetic result.
Bilozetskyi Ivan
