Nasoethmoidal and Le Fort Iii Facial Fractures
Robert M. Kellman
The fractures discussed in this section are typically described as high-energy or high-velocity or high-impact injuries to the facial skeleton. The nasoethmoid complex (NEC) fracture is also known as the naso-orbital ethmoid (NOE) fracture, both names being attempts to describe the clinical and anatomic components of the bone injuries involved. These types of fractures occur when a force is directed primarily to the area of the root of the nose. The solid nasal root may or may not fracture, but frequently, the thin medial orbital wall bones behind the nasal root will be compromised (Stranc described this fracture as an “ethmoid crush”), allowing the nasal root to “telescope” inward into the area of the ethmoid sinuses. The loss of support of the lacrimal bones often results in disarticulation of the medial canthal ligaments (with or without bony attachments), thereby often resulting in lateral displacement of the medial canthal ligaments or “telecanthus.” The injury creates the appearance of hypertelorism, often called “pseudohypertelorism,” since the orbits themselves are not actually displaced laterally as the term hypertelorism implies. The term NEC fracture or NOE fracture refers to the fractures of the bones involved (Fig. 52.1).
The Le Fort III fracture refers to the most serious level of the Le Fort fracture series, otherwise known as the “craniofacial separation.” The Le Fort I, II, and III fractures were described by Rene Le Fort in 1901. They refer to primarily horizontal fractures that traverse the facial skeleton between the maxillary dentition and the upper face or cranium. The Le Fort III fracture breaks through the lateral and medial orbital walls, crosses the nasal root and nasal septum, and is completed by extending across the posterior floor of the orbits and the zygomatic arches, as well as the pterygoid plates posteriorly. This results in a complete separation of the midfacial bones from the cranial portion of the skeleton (Fig. 52.2).
The NEC fractures may occur together with or independently from the Le Fort III fractures.
In civilian life, most NEC and Le Fort III fractures are the result of high-velocity injuries as might typically be seen in motor vehicle accidents (particularly when seat belts are not worn and/or air bags are not deployed), industrial accidents, and direct assaults to the central face using heavy instruments, such as a pipe or baseball bat. Intracranial injuries may be associated, and a complete history, including loss of consciousness, should be elicited. Symptoms and/or signs of neurologic injury are common, and changes in vision may be present as well. Though difficult to determine when the nose is filled with blood, the possibility of anosmia should be considered.
Of course, other comorbidities should be considered as well. It is important to determine if drugs and/or alcohol played a role in the patient’s condition, as it may impact medical management and the timing of surgery. These issues may also affect the patient’s ability to cooperate with postoperative care.
The ABCs of trauma must first be addressed. It is of course important to assure that the patient is neurologically stable and that there is no impending loss of vision due to increasing intraocular pressure or other cause of pressure on the optic nerve(s).
The tell tale findings of an NEC (NOE) fracture include telecanthus (widening of the intercanthal distance) and depression of the nasal root, which may or may not be associated with the appearance of nasal shortening (Figs. 52.3 and 52.4). Telecanthus may not be obvious initially due to edema as well as the possibility of slow lateralization of the medial canthal ligament. Typically, it is stated that the distance between the medial canthi should be about half the interpupillary distance or equal to the horizontal palpebral fissure length (Fig. 52.5). Also, the midline between the brows should be marked, and the distance to each medial canthus should be equal. Note that the midline of the nose is often difficult to use due to trauma-associated alterations. An epicanthal fold may sometimes develop as well. Lateral distraction of the medial canthus may be attempted to assess for detachment. Additionally, some surgeons advocate performing bimanual palpation of the bone underlying the medial canthal attachment using an instrument placed inside the nasal cavity and a finger outside. Note that the detached tendon tends to drift laterally, inferiorly, and anteriorly over time, creating a most unsightly deformity.
In a complete (bilateral) Le Fort III fracture, the midface may be freely mobile relative to the frontal skull. If possible, the anterior maxillary alveolus is grasped firmly in one hand, while the other hand is placed on the frontal bone and an attempt is made to gently rock the maxillary alveolus. If motion is detected relative to the frontal bone, a Le Fort fracture is present. Depending upon the level at which the movement takes place, it is often possible to clinically assess the level of a Le Fort fracture. In a Le Fort III fracture, the movement includes the entire midface relative to the frontal skull.
It is important to evaluate visual acuity and motion of the globe. A complete retinal examination should be completed by an Ophthalmologist. A retinal tear or globe rupture may require delaying the repair of the periorbital bones, and of course, a significant rupture of the globe may require enucleation. The presence of a hyphema may preclude proper visualization of the retina and should be documented if present. The position of the globe should also be evaluated, looking for both the anterior-posterior position (enophthalmos, exophthalmos) and vertical position (hypophthalmos, hyperophthalmos).
If there is any nasal discharge, the possibility of cerebrospinal fluid (CSF) leak should be considered, and appropriate steps are taken to assess and manage this. A complete examination of the cranial nerves is essential and should be performed in all trauma patients.
Appropriate consultations should be obtained. Since these fractures involve the bones of the orbit, there is significant potential for ocular and periocular injury, so evaluation by an Ophthalmologist is important. Similarly, if there is concern for intracranial injury, a Neurosurgeon should be consulted. It is important to note that concussion tends to be underdiagnosed in facial trauma, so this possibility should be entertained.
Fractures involving the NEC (NOE fractures) as a rule require surgical repair. When the medial canthal ligament is either detached or if the bone to which it is attached is fractured and freed from the surrounding bone, the natural tendency is for the medial canthus to lateralize. It also tends to move anteriorly and inferiorly over time. This creates an unsightly appearance, and the earlier that it is repaired, the better the outcome is likely to be. Therefore, so long as there are no contraindications, surgical repair is indicated.
Le Fort III fractures generally create instability of the midfacial complex. Left unrepaired, these typically lead to malocclusion and midface malposition (typically either lengthening or foreshortening). Posterior displacement often results in lateral protrusion of the convexity of the zygomatic arch with associated midface widening. Therefore, proper repair is generally indicated, including stabilization of the occlusion and fixation of the bones. Similarly, globe malposition and/or orbital dystopia are indications for repair.
Contraindications may be related to the injury, or they may be due to other patient problems. First the patient has to be medically/hemodynamically stable for surgery. Repair of these fractures typically involves a coronal flap and a sublabial exposure and may also require orbital exploration, so hemodynamic stability is important for surgery of such magnitude. Coagulation issues may also pose a problem as well.
FIGURE 52.4 Photo of a patient with a unilateral injury that has been allowed to heal without surgery. Note the obvious lateral and inferior displacement, with less apparent inferior displacement of the medial canthus.
Ocular injury may be a contraindication to surgical manipulation of the orbital bones, particularly if there is a repaired globe rupture or a retinal injury. A hyphema may preclude evaluation of the retina and may mandate delay of surgical repair.
Brain injury may also be a contraindication, particularly if there is significant edema.
In general, Ophthalmology and Neurosurgical clearances are a good way to assure that the patient is ready for surgery. Injury to the cervical spine must be thoroughly evaluated and requires precautions at the time of surgery.