1 Principles top
Considerations related to dental occlusion render nasotracheal intubation necessary. If that is not feasible, primary submental/submandibular intubation should be considered. Depending on the patient’s general condition, a tracheostomy might also be considered.
The aim of successful reconstruction of midface fractures is reestablishing the midfacial buttresses. These pillars can serve an even more important role in patients who lack dentition (partial or completely edentulous patients).
A principle in all Le Fort fractures is to reestablish the premorbid dental occlusion. Portions of the pterygoid plates and associated musculature are still attached to the posterior portion of the maxilla, so passive mobilization of the fracture can be difficult. Without passive mobilization, Class III tendency occurs often in the postoperative period. The reason for this is that when patients are placed into MMF during the surgery, the soft-tissue tension from the attached musculature distalizes the mandibular condyles in the glenoid fossae. When the MMF is removed, the condyles re-seat themselves into their normal position, bringing the mandibular dentition forward, creating a Class III malocclusion. In order to properly achieve a passive position of the maxilla, the maxilla requires strong mobilization forces using various instrumentation: Rowe’s disimpaction forceps, “Stromeyer” hook, Tessier retromaxillary mobilizers, etc.
The goal is to achieve an anatomical correct repositioning by means of 3-D reconstruction. If available, dental cast, stereolithographic models, and/or premorbid photographs may be useful guides for treatment.
As a general principle, all fractures should be exposed and reduced before plating.
Choice of implant
It is difficult to give absolute guidelines as to the strength of the plates to be used at the three key points of fixation for a Le Fort III fracture. There is considerable variability as to how unstable or comminuted the fractures may be. Furthermore, the majority of Le Fort III fractures are also associated with a plethora of other midface fractures. This has further impact on deciding the size and strength of the plate to be used. Finally, in many cases of Le Fort III fractures with other panfacial trauma, many surgeons may choose to leave the patient in MMF for a period of time postoperatively. This has a further impact in deciding whether a larger or smaller plate is adequate.
Older texts often recommended using a larger compression plate at the zygomaticofrontal suture. The soft-tissue coverage over this area is very thin, and patients are likely to complain if the plate is palpable. Furthermore, compression plating at this location is not necessary.
Generally, a smaller straight plate is adequate at the zygomaticofrontal area. A variety of different plates may be used at the nasofrontal area. Options include one or two straight plates, or various configurations of Y- or X-plates.
Click here for a description of implant options.
Choice of approach
The number of approaches depends on the amount of dislocation, comminution, and the degree of stability following reduction.
A Le Fort II fracture includes a fracture of the nasofrontal junction. In a pure Le Fort II fracture, the fracture extends through the infraorbital rim. It also includes fractures through the zygomaticomaxillary buttress.
Some Le Fort II fractures can be treated exclusively through a maxillary vestibular approach. Plate fixation at the zygomaticomaxillary buttresses may be sufficient to adequately stabilize a mobilized and repositioned Le Fort II fracture.
If plating of the inferior orbital rims is deemed necessary, it can be achieved through a lower eyelid incision, or in some cases through a maxillary vestibular approach.
The surgeon has to decide whether a plate needs to be placed at the nasofrontal junction. In many cases, closed reduction of the fracture at the nasofrontal junction may be considered.
If it is necessary to gain exposure in the area of the nasofrontal junction, the surgeon must decide whether to perform a coronal incision or a local one such as the glabellar incision. A glabellar incision may be particular desirable in an elderly patient who commonly has frown lines in the area of the glabella, or in a patient who wears eyeglasses, where the frame may help to cover the glabellar incision.
Although a coronal incision offers excellent exposure, there can be significant disadvantages with this incision.
A Le Fort III fracture involves fractures of the internal orbit. If significant, these orbital fractures may be treated in the same way as other orbital fractures in this location. Click here for further details on the reconstruction of combined medial wall and orbital floor fractures.
2 Reduction topenlarge
Arch bars and mobilization
First, arch bars are secured to the dentition. Click here for a detailed description of mandibulomaxillary fixation.
After exposure of the fracture segments by adequate approaches, the fractures have to be mobilized to enable reduction and fixation.
Reduction instruments - Use of Rowe disimpaction forceps
The Rowe disimpaction forces are side specific. They allow precise 3-D movement of fracture fragments of the centrally impacted midface or maxilla.
Note: Special attention has to be given to the patient’s individual fracture pattern so that the use of these instruments does not result in significant shearing at the skull base or orbit. Otherwise, severe complications such as blindness can occur.
Special attention has to be paid regarding the correct placement of the Rowe
disimpaction forceps so that the upper anterior dentition is not harmed.
The maxillary fracture is completely mobilized and an attempt should be made to make the fragment as passive as possible. This may require an up-down and side-to-side movement of the forceps.
Reduction instruments - Use of bone hooks
According to regional preferences and various schools of teaching, different bone hooks are used for fracture reduction in the lateral midfacial area.
Reduction hook (Stromeyer hook)
The Stromeyer hook (Georg Friederich Louis Stromeyer, Hannover, Germany, 1804-1876) is very versatile for transoral and transcutaneous reduction of lateral midfacial fractures. Its main indication is to reduce zygoma or zygomatic arch fractures.
In selected cases the Stromeyer hook can also be used for manipulating the Le Fort complex by hooking the tip of the instrument inside the piriform aperture and pulling downwards and anteriorly. This technique is called downfracture procedure in Le Fort osteotomies.
For zygoma reduction the tip of the Stromeyer hook is inserted transcutaneously. The curvature of the Stromeyer is held between the index finger and the thumb. The tip of the hook is then inserted about 4 cm below the lateral canthus either directly through the skin or following a limited stab incision.
After controlled positioning of the instrument, the hook is placed below the fracture segment and reduction can be obtained by pulling in the necessary vector. Care has to be taken so that the direction of pull on the hook is not changed, causing dislocation of the hook which could result in injury to the orbit or soft tissues.
Reduction instruments - Use of threaded reduction tool
The threaded reduction tool (Carroll-Girard technique) might be helpful to
3-D position the midface.
The tip of the tool is self-drilling which generally requires no predrilling, but support of the mobile fragment is required to withstand the force resulting from the insertion of the instrument.
The T-handle allows excellent manipulation of a solid bony structure like the zygoma, in a Le Fort III fracture. Insertion of the threaded reduction tool is usually done after limited stab incision.
3 Fixation topenlarge
According to the quality and stability of the reduction, the final decision is made regarding the number of plates and screws, and the design of the plates.
Generally, for Le Fort III fractures, plate fixation is applied to the fractures at the zygomatic arch, the frontozygomatic area, and the nasofrontal junction.
Fixation usually starts at the most reliably reduced buttress, always considering any fracture line in all three dimensions. If reduction is satisfactory, the first plate can be fixed by filling an adequate number of screws into the plate holes. Due to the specific patient injury patterns, provisional fixation with a limited number of screws may be indicated (in special cases, even temporary wire fixation might be considered). Final fixation must include two screws per fracture side.
The remaining buttresses are similarly addressed.
Complete reduction and fixation of the Le Fort fractures should take place before addressing the internal orbital wall fractures.
If there are any significant orbital fractures that require fixation or plating, these are performed after complete reduction and stabilization of the Le Fort III fracture.
In the case shown, the first plate is applied to the right lateral orbital buttress. According to the fracture morphology, a plate of appropriate profile, shape, and length is selected and contoured using bending pliers.
The plate is positioned with appropriate instruments (eg, forceps, plate holders, gauze packer). The first hole is drilled (a drill bit with a stop may be used) next to the fracture line in the frontal process of the zygoma and a screw is inserted.
Second screw in first plate
After drilling, the second screw is inserted next to the fracture line on the opposite side of the fracture.
Insertion of remaining screws
If reduction is satisfactory at the other fracture lines, the remaining screws are inserted (at least two screws per fracture fragment).
Alternatively, these two screws can be inserted after all other plates have been applied.
Contralateral frontozygomatic buttress
In the illustrated case the contralateral frontozygomatic buttress is fixed in the same manner.
Additional plates (if required)
For isolated Le Fort III fractures, bilateral frontozygomatic fixation may be sufficient; more commonly, additional points of fixation are needed.
Depending on the fracture pattern, one or two appropriate plates are applied. In this illustrated case, an inverted Y-plate is used for further reduction and stability at the nasofrontal fracture.
Zygomatic arch plate
If stability of the specific patient’s fracture morphology requires additional fixation, plates can be applied to the zygomatic arches in order to reestablish these sagittal buttresses.
Plate fixation normally uses straight plates. As with other fractures, at least two screws should be placed on each side of the fracture line, when possible. The number, length, and size of screws vary according to patient anatomy.
In case of a fracture of the zygomatic arch near the temporal bone, screw fixation (position screw or lag screw) may be considered. Care has to be taken to choose the correct implant dimension and length so that the neighboring structures are not harmed. The use of drill bits with a drill stop should be considered in this area.
Click here for further details – see “Options to consider for arch reconstruction”.
After internal fixation has been completed, MMF is released and the occlusion checked.
If an open bite and/or Class III tendency occurs when checking the occlusion, one or both mandibular condyles were malposed in posterior and/or inferior direction. In such cases, it is necessary to remove the bone plates, reapply MMF, and passively reposition the maxillomandibular complex again, assuring the condyles are properly seated. Bone plates are again applied and the occlusion verified.
The reason for a malocclusion may be the fact that the condylar heads were not positioned correctly in their respective glenoid fossae when securing MMF (as illustrated).
Illustration showing the subsequent malocclusion.