■ Part 2. Operative Technique and Exemplary Repair
Permutations of nasal-nasoseptal, nasomaxillary, orbito-ethmoid, and orbitosphenoid injury in the adult are evident clinically and in the laboratory after induced trauma. The structure of the nose and frontal processes of the maxilla, and orbitoethmoid, and orbitosphenoid complexes (with recognized regional differences in bone, cartilage and fascia) warrants that distal injuries will differ from those more proximal.
The nasal-nasoseptal injury may be confined to soft tissue and cartilage, such as the alar cartilages, lateral nasal cartilages, and nasal septum, in great part due to the resilience of cartilage and the interalar (nasal tip) fascial aponeurosis.10 The nasal bones per se avoid injury or may be minimally harmed by low-velocity impact; more often than not, however, fracture of one or both nasal bones extends to involve the anterior edge of the frontal processes of the maxilla,11 where the maxillary bone is thin, tapered, and nearly equally vulnerable to damage. In radiographic reports, involvement of the frontal processes may be minimized.
As velocity of impact increases, more extensive involvement of the frontal processes of the maxilla is witnessed, and the fractures become nasomaxillary in their reach. The nasomaxillary fragments are key to the repair of the medial orbital frame and are best aligned before repair of the inferior orbital rim and zygoma. Failure to first restore the anatomic position of the medial orbital frame inappropriately biases realignment of the inferior orbital frame and zygoma.20 The medial canthal ligament may be displaced or separated from its mooring, particularly with comminution.
As load forces extend beyond the frontal processes of the maxilla, the impact triggers a proverbial “house of cards,” and the fractures become orbitoethmoid and orbitosphenoid in scope. The frontal processes of the maxilla and lacrimal bone unhinge from the frontal boss; the usually tight fit at the nasofrontal suture defaults. The anterior orbitoethmoid buttress (linking the posterior portion of the lacrimal bone, inferior turbinate, and anterior medial maxillary) wall succumbs. The bilge of the orbital floor (see Chapter 8), the roots of the superior and middle turbinates, and the ethmoid labyrinth, all hinged from the parasagittal aspect of the cribriform plate, are sheared from their attachment. The struts (“microbut-tresses”) within and across the walls, roof, and floor of the ethmoid sinus collapse and buckle ( Fig. 7.10 ).
The orbitosphenoid buttress (lesser wing of the phe-noid medial to the outlet of the optic foramen, the orbital process of the palatine bone, and the posterior wall of the maxilla) is but a short distance away.
In its most extreme presentation, the fractures through the sphenoid become basilar to end at one of several foramina in the greater wing of the sphenoid (foramen ovale, foramen lacerum, foramen spinosum, or the carotid canal [see Chapter 6]). Further, injuries this extreme often compromise the optic canal and the content of various foramina at the orbital apex.
Management of Fractures of the Central Upper Face in Days Past
Fractures of the central upper face have not always been managed the way they are today. In Ancient Egypt, for example, nasal fractures were among “those to be treated,” as opposed to “those not.” The nostrils were first cleansed of blood and debris, and the fragments were then to be reduced by digital manipulation. Finally, linen plugs were to be inserted into each nasal vault, and oil-soaked linen wraps were added to provide support.
Instruction regarding central upper craniofacial fractures was explicit. Case XIII of the Smith Papyrus admonishes the practitioner, in the presence of “a compound fracture . . . of the nose, . . . that crepitates under thy fingers . . ., though should say concerning him: One having a smash in the nostril is an ailment not to be treated.”
These Egyptian dictates were followed in kind in Ancient Greece and Ancient Rome, but greater emphasis was placed on the application of oil-soaked linens to stabilize the fragments after manipulation. The dressings by Hippocrates and by Menecrates, respectively, were favorites over the centuries21 ( Fig. 7.11A,B ).
During the European Wars (1852 to 1870) and World War I (1914 to 1918), management of nasal fractures differed little from that offered in ancient times.22 During World War II, the Korean War, and the Vietnam Conflict, manipulation of the fragments with Walsham or Asche forceps was favored, followed by the application of linen dressings or tin nasal splints reinforced with gutta-percha.23
In the presence of comminution and instability, trans-nasal horizontal mattress stainless steel wire was passed beneath the fragments and through the septum, using a curved Hagedorn abdominal cutting needle. The wire was tied over lead plates at each sidewall of the nose. In cases where outward and upward suspension was desired, a plaster of Paris headcap was chosen as an adjunct ( Fig. 7.12 ).
Preoperative Assessment and Indications for Repair
Because the nose projects beyond the plane of the cran-iofacial skeleton, injuries to nasal structures are common. The nasal injury may be confined to soft tissue (such as the dorsal suspensory ligament ) and cartilage (such as the alar cartilages, lateral nasal cartilages, and nasal septum), and the nasal bones may be minimally involved after low-velocity impact, thus nasal-nasoseptal . More often than not, however, when load forces are sufficient, fracture of one or both nasal bones extends to involve the edge of the frontal processes of the maxilla, where the maxillary bone is thin, tapered, and vulnerable.
When load forces reach the thicker portions of the frontal process of the maxilla, the fracture is said to be nasomax-illary, and attachment of the medial canthal tendon is put at risk. If the frontal processes do not withstand the impact, the next compartment (the orbitoethmoid complex) becomes vulnerable to comminution, particularly the orbitoethmoid buttress . Fracture of all three compartments (naso-nasoseptal, nasomaxillary, and orbitoethmoid) is colloquially referred to as a nasoethmoid fracture. When load forces fracture the orbitosphenoid buttress, fractures, as noted previously, may extend to the sphenoid sinus and center of the skull base.
Swelling and ecchymosis are generally proportional to the extent of the injury and may camouflage the more subtle injury, such as avulsion of the dorsal suspensory ligament and lateral nasal cartilage from the under surface of the nasal bone. Avulsion may be apparent only with serial preoperative examination, during surgery (after reduction and realignment of fractured bone), or after months of postoperative healing.
Spraying the mucosa of the nasal vault with vasoconstrict-ing agent and examination with a magnifying otoscope or fiber-optic nasal scope favors the discovery of septal cartilage and ethmoid plate deflection, rents in the nasal mucosa, or nasoseptal hematoma. Blood confined to the plane anterior to the orbital septum (beneath the fascia of the periorbital musculature) presents as a “spectacle hematoma.”
Foreshortened nasal bones are more vulnerable to impact than an upper nasal vault of normal proportion. The nasal bones are foreshortened in the patient with short nasal bone syndrome, and the lateral nasal cartilages are relatively elongated.10
This atypical nasal architecture is vulnerable, and greater offloads are dispersed to and from the lateral nasal cartilages, the proximal septum, the nasofrontal suture, and the frontal process of the maxilla. Rupture of the dorsal suspensory ligament and nasal cartilage avulsion from the undersurface of the nasal bone(s) is more commonly noted, and unilateral nasomaxillary fracture is more frequently present. Involvement of the anterior orbitoethmoid buttress in patients with “short nasal bone syndrome” is probable ( Fig. 7.13 ).
A saddle nose deformity commonly follows comminuted nasal and nasomaxillary fracture. The “saddle” may be more apparent when the anterior orbitoethmoid buttress “gives way,” the ethmoid lateral masses 14 (cross-struts) collapse, and the medial walls of the orbit buckle, creating a flattening of the central upper face. In adolescence and young adulthood, these changes may misleadingly appear to be unilateral in the presence of edema.
Initial inspection focuses on the position (height, projection, and width) of the nasal tripod.20 After nasomaxillary and particularly after orbitoethmoid comminution, the nasal pyramid is observed to be displaced inwardly as the pyramid is engulfed by the central void. The nasal pyramid is displaced as an intact unit in the adult if ossification of the internasal suture has occurred associated with a loss of nasal height, flattening of the nasal dorsum, and loss of distal septal support. Distal nasal bones, as illustrated in Fig. 7.14 , are usually comminuted. The intact proximal nasal bones and medial orbital frame are driven downward and backward, disrupting the orbitoethmoid buttress (created by the orbital plate of the lacrimal, the lacrimal process of the inferior turbinate, and the upper medial wall of the maxillary sinus) and the adjacent medial orbital wall. A frontal blow of sufficient intensity may fracture the orbitosphenoid buttress and the anterior wall of the sphenoid sinus, further deepening signs of central upper facial collapse ( Fig. 7.14 ).
Increased intercanthal distance, or telecanthus, is characteristic and the next focus of examination. Gentle palpation reveals a discontinuity or “step-off” of the medial orbital frame, either below or above the medial can-thal tendon. Firm pressure over the fragmented medial orbital frame may provoke mobility and a palpable “click.” Step-offs may be multiple in the presence of comminution. The integrity of the medial canthal tendon may be confirmed under local anesthesia preoperatively by inserting instruments high in the nasal vault, but the exam is usually deferred so that it may be correctly achieved under general anesthesia and careful use of instrumentation.24
Basic ocular assessment is achieved in five steps, avoiding meaningless generalities such as “examination grossly normal” or “pupils equal, round, reactive to light and accommodation,” as follows:
Distant and near vision, with one eye occluded, is noted; if vision is so challenged that fine print cannot be read, the ability to count fingers should be noted.
The size and shape of the pupils is charted; reaction of the pupils to bright light, particularly the presence or absence of the afferent pupillary defect, is critical; direct pupillary response to alternating light, as it passes briskly between the two eyes, is readily tested.
Clarity of the cornea and anterior chambers is recorded, searching for hemorrhage and asymmetries.
Direct ophthalmoscopic examination, looking for the presence of a red reflex, the macula, the optic nerve head, and the absence of enfolding of the retina.