In planning reconstructive surgery for complex trauma to the craniomaxillofacial region, it is advisable to distinguish three topographic areas:
- the midface
- the mandible
- parts of the neurocranium and skull base
The anatomic region between the maxillary teeth and the infraorbital margin is referred to as the midface.
Midface fractures typically affect certain areas.
Le Fort was the first to classify the characteristics of these fractures.
Le Fort's fracture classification is based on experimental examinations of dried skull bones and comprises three levels of fracture along commonly occurring lines.
Transverse fractures of the maxilla (outside the line of teeth) with typical lines of fracture: #pic#
Le Fort I
Disarticulation of tooth-bearing part of the maxilla at the level of the floor of nose and maxillary sinuses (low level fracture of the maxilla).
The fracture line passes above the teeth roots, traversing the piriform aperture through the maxillary sinus and the pterygoid process.
Fracture line: Piriform aperture, lateral antral wall, pterygoid process of the sphenoid bone
Le Fort II
Disarticulation of the maxilla and the nasal skeleton (pyramidal fracture of the maxilla)
The fracture line passes bilaterally from and through the nasal root caudal to the fronto-nasal suture via the lacrimal bone and the orbital plate of the ethmoidal bone to the anterior and middle parts of the orbital floor, the middle part of the infraorbital margin, from there proceeding to the posterior antral wall via the lateral antral wall in an arch around the zygomatico-alveolar crest, thus completely separating the pterygoid processes in the middle third, with additional fractures of the bony part of the nasal septum, the vomer and perpendicular plates of the ethmoidal bone.
Fracture line: Above or inside the nasal bones, medial orbital wall, inferior orbital fissure, infraorbital foramen, supero- lateral antral wall, pterygoid process.
Le Fort III
Disarticulation of the maxilla, the zygomatic bone and the nasal skeleton (high level fracture of the midface)
The fracture line passes medially-caudally to the fronto-nasal and fronto-maxillary suture via the lacrimal bone, the medial orbital wall, the orbital floor up to the inferior orbital fissure. From there, it extends caudally through the pterygopalatine fossa to the base of the pterygoid processes as well as from the anterior end of the inferior orbital fissure along the lateral orbital wall to the frontozygomatic fissure. The fracture of the midface is completed by the fracture of the zygomatic arch and the cranial bony part of the nasal septum.
Le Fort III complex fractures of maxilla, zygomatic bone and nasal skeleton are relatively rare.
Possible combined fractures of the midface are:
- Le Fort II fracture with fracture of the zygomatic bone
- Le Fort I fracture with additional sagittal fracture
- Unilateral or bilateral Le Fort II fractures combined with a unilateral fracture of the zygomatic bone
In modern clinical practice, easily classifiable fractures of maxilla and mandible along anatomically weak points (Le Fort) rarely occur.
Most injuries are complex fractures, often associated with comminuted fractures and major defects/bone loss. Therefore, the necessity of a more treatment-related classification has been recognised.
Midface fractures are therefore classified according to their general position.
Lateral fractures (e.g. fractures of the zygomatic bone), centro-lateral fractures (e.g. Le Fort III), and central midface fractures (e.g. Le Fort I and II, nasal bone and sagittal maxillary fractures) are differentiated.
additional classification system according to the affected region of the midface is also used:
- zygomatico-orbital complex (zygomatic bone, orbital floor),
- nasomaxillary complex (region around the piriform aperture),
- naso(orbito)-ethmoidal complex (ethmoid bone region),
- dento-alveolar complex.
Le Fort's classification, however, is still useful as a general and additional description of midface fractures as well as in orthognathic surgery.
The mandible is often subject to damage from trauma in the area of the viscerocranium. Approx. 70 % of all viscerocranial fractures are mandibular fractures. Multiple fractures are common in the mandible.
- Fractures of the mandibular body
- Median fractures
- Paramedian fractures
- Mandibular angle fractures
- Fractures of the ramus
- Condylar neck fractures
- Intra-capsular fractures
- Fractures of the neurocranium
- Fronto-basal fractures
- Fractures of the anterior wall of the frontal sinus
- Fractures of the posterior wall of the frontal sinus
- Fractures of the orbital roof
- Fractures of the base of the skull
A particular challenge for treatment are panfacial fractures in which, by definition, the entire skull is involved and reference points to the base of the skull are lost, as well as combined trauma of the neurocranium and viscerocranium referred to as craniofacial trauma (Dempf and Hausamen 2000).