![]() ![]() Improved understanding of the response of the intact face to stress is required to develop a better classification system for facial fractures and to improve reconstructive techniques. Moreover, when the response of the complete skull to trauma has been studied, it has been to a bare skull or model, which ignores the contribution of the musculature to force distribution ( 14, 17, 18). These studies also fail to capture the complexity of the facial buttress system. Because of its complexity, several groups have taken a reductionist approach to studying the face and have focused on individual components in isolation ( 14– 16). The craniofacial skeleton distributes forces over a complex series of buttresses, heavily influenced by musculature ( 1). The bones of the face are more complex than those in the axial skeleton. This level of understanding has not, however, been achieved for the face ( 13). This detailed understanding has enabled the development of model systems for the femur that accurately classify these fractures and improve reconstruction techniques ( 11). The study of long bones provides an example for which strength and failure points in response to compressive, torsional, tensile and shear forces have been studied extensively ( 9– 12). ![]() The development of a more sophisticated classification system for facial fractures relies on a better understanding of force distribution in the craniofacial skeleton during trauma. ![]() However, Le Fort’s system for the classification of facial fractures remains ubiquitous. We also know that many facial fractures do not fit Le Fort’s classification ( 1– 8). Through continued surgical experience, our understanding of the horizontal and vertical buttress systems of the face and their importance for successful reconstruction have become more nuanced ( 1– 3). This system was developed through direct observation, and incorporates what Le Fort described as “great lines of weakness” in the craniofacial skeleton. Réné Le Fort’s seminal classification system for midface fractures has been the standard for >100 years. Le test de Wilcoxon a été privilégié pour comparer la hauteur des fractures causées par des traumatismes à haute et à faible vélocité. Aux fins de comparaison, les valeurs étaient exprimées selon le ratio de l’endroit sur le visage par rapport à ces points de repère. La position verticale de chaque fracture était mesurée à son point d’entrée sur la structure latérale et à son point de sortie dans l’orifice piriforme. Les fractures de faible vélocité découlaient d’une agression à l’arme contondante ou au poing fermé ou de chutes à partir de la position debout. Les fractures de haute vélocité étaient causées par des chutes de plus d’un étage ou un accident d’automobile. Ils ont extrait les caractéristiques démographiques des patients, le mode de traumatisme et la vélocité de l’impact, exprimée la vélocité deux catégories : « haute » ou « faible ». De ce nombre, ils ont repéré 39 fractures de Le Fort. Les chercheurs ont effectué une analyse rétrospective des dossiers médicaux d’une cohorte consécutive de traumatisés craniofaciaux opérés par un même chirurgien entre 2007 et 2011 (n=150). A Wilcoxon rank-sum test was used to compare the fracture heights caused by high- and low-velocity trauma. To allow for comparison across individuals, values were expressed as ratios based on their location on the face relative to these landmarks. The vertical position of each fracture was measured at its point of entry on the lateral buttress and its point of exit on the piriform aperture. Velocity of impact was expressed categorically as either ‘high’ or ‘low’: high-velocity fractures were those caused by a fall from >1 story or a motor vehicle collision low-velocity fractures were the result of assaults with a blunt weapon, closed fist or falls from standing height. Patient demographic information, method of trauma and velocity of impact were reviewed for these cases. Of these cases, 39 Le Fort fractures were identified. All rights reserved.A retrospective medical record review was conducted on a consecutive cohort of craniofacial traumas surgically treated by a single surgeon between 20 (n=150). Published by Houghton Mifflin Harcourt Publishing Company. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. The American Heritage® Student Science Dictionary, Second Edition. ![]()
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