Case 20

Discussion:

Common to all Le Fort fractures is fracture of the pterygoid processes. Le Fort injuries are commonly asymmetric or compound.

Le Fort I fractures, also known as Guerin fractures or ‘floating palate’, usually involve the inferior nasal aperture. The fracture extends from the nasal septum to the lateral pyriform rims, extends horizontally above the teeth apices, crosses below the zygomaticomaxillary junction, and traverses the pterygomaxillary junction to interrupt the pterygoid plates. May occur in isolation or in association with le Fort II and III fracture.

Le Fort II fractures have a pyramidal shape and extend from the nasal bridge at or below the nasofrontal suture through the frontal processes of the maxilla, inferolaterally through the lacrimal bones and inferior orbital floor and rim through or near the inferior orbital foramen, and inferiorly through the anterior wall of the maxillary sinus; it then travels under the zygoma, across the pterygomaxillary fissure, and through the ptergoid plates

Le Fort III fractures follow impact to the nasal bridge or upper maxilla. These fractures start at the nasofrontal and frontomaxillary sutures and extend posteriorly along the medial wall of the orbit through the nasolacrimal groove and ethmoid bones. The fracture continues along the floor of the orbit along the inferior orbital fissure and continues superolaterally through the lateral orbital wall, through the zygomaticofrontal junction and the zygomatic arch. Intranasally, a branch of the fracture extends through the base of the perpendicular plate of the ethmoid, through the vomer, and through the interface of the pterygoid plates to the base of the sphenoid.

References:

• James T. Rhea1,2 and Robert A. Novelline1 How to Simplify the CT Diagnosis of Le Fort Fractures. AJR 2005; 184:1700-1705