Nasal Bone Fractures: Analysis of 1193 Cases with an Emphasis on Coincident Adjacent Fractures.

The nasal bone is one of the most commonly fractured bones of the midface. However, the frequency of coincident fractures of adjacent bones such as the frontal process of the maxillary bone, nasal septum, and medial or inferior orbital walls has not been fully evaluated. The purpose of this study was to investigate the incidence of fractures of adjacent structures in the setting of a nasal bone fracture. Second, we propose a new classification system of nasal bone fractures with involvement of adjacent bony structures. One thousand, one hundred ninety-three patients with midfacial fractures were retrospectively reviewed. The characteristics of fractures of the nasal bone and the incidence of coincident fractures of the frontal process of maxilla, bony nasal septum, medial, or inferior orbital walls were analyzed. All patients included in the study presented with nasal trauma. The coincident fractures of adjacent midfacial structures were assessed, and a new classification of midfacial fractures based on computed tomography (CT) scan images was proposed. Among the 1193 cases, bilateral fractures of the nasal bone were most common (69.24%), and coexistent fracture of the frontal process of the maxilla and bony nasal septum was 66.89% and 42.25%, respectively. Coincident fracture of the orbital walls was observed in 16.51% of cases. The major etiology of fracture for the younger and elderly groups was falls, compared with assault as the most common etiology in the adult group. A classification scheme was generated in which fractures of the nasal bone were divided into five types depending on coexisting fractures of adjacent structures. External force applied to the nasal bone can also lead to coexistent fracture of adjacent bony structures including the frontal process of the maxilla, nasal septum, and orbital walls. The proposed classification of nasal fracture based on CT imaging helps to incorporate coincident disruption of adjacent structures.