Diagenetic and structural aspects of tight gas sandstones must be addressed concurrently in order to fully understand low-permeability sandstones and to better predict their reservoir quality attributes that arise from a combination of pore-scale and fracture distribution characteristics. This dissertation focuses on aspects of rock evolution that are germane to concurrent structural and diagenetic evolution, such as loading and thermal history, rock mechanical property evolution, and fracture timing. I tested the hypothesis that the cement precipitation step, governed by thermal exposure and grain surface attributes, governs how sandstone attributes evolve using observations from the Late Cretaceous Williams Fork sandstones from the Piceance Basin, Colorado. My research shows that essential information for predicting and understanding fracture patterns in sandstone can be obtained by unraveling cement precipitation (diagenetic) history. Fractures depend on the mechanical properties existing during fracture growth. I show that key rock mechanical properties (subcritical crack index, Young's modulus and Poisson's ratio), petrophysical behavior, and reservoir quality depend in a systematic way on time-temperature history and the intrinsic grain surface attributes of these sandstones. I classified the Williams Fork lithofacies petrographically and correlated those with log responses to create a model that can be used to predict reservoir quality and diagenesis directly from well logs. I determined rock mechanical characteristics by measuring the subcritical crack index (SCI), a mechanical property that influences fracture distribution characteristics, and by examining log-derived bulk mechanical properties. To quantify the influence of quartz cementation on the SCI and to determine the range of SCI values for sandstone of given framework composition at different diagenetic stages, I measured SCI on Williams Fork core samples and their outcrop equivalents. Diagenetic modeling is applied to determine the sandstone characteristics during fracturing. / text

<p>Impact craters are formed when a large meteorite or comethits the Earth. At the impact a shock wave is released causingabundant fracturing in the surrounding bedrock. This type offracturing is intense and occurs throughout a very large volume(>100 km³) of the bedrock. Fractures of this type have beenobserved in deep drilling, to 5 km depth, in thePuchezh-Katunki Impact Crater. At theses depths the ambienttemperature is high. Thus impact structures are candidates forpotential heat-exchange sources for extraction of geothermalenergy.</p><p>There is a relation between fracture intensity and electricresistivity in bedrock predominated by impact-generatedfractures. In crystalline bedrock changes in electricresistivity is mainly due to fracturing which is the mainsource of porosity in these rocks. Electric resistivity methodsare highly sensitivity to porosity. Furthermore highfracture-intensities have generally been associated with lowelectric resistivity. Electro-magnetic methods like Very LowFrequency Resistivity (VLF-R) and Magnetotellurics (MT) canindirectly measure electric resistivity to relatively largedepths in the bedrock.</p><p>This study will quantify the relationship between fractureintensity and electric resistivity which can be used as aprospecting tool for geothermal energy resources at largedepth.</p><p>To meet that end, a method for fracture mapping on outcropsin Swedish terrain and a method to calculate thethree-dimensional fracture frequency from two-dimensionalfracture data has been developed. The fracture traces measuredin two dimensions on outcrops are assumed to represent avertical surface and must be converted to a three-dimensionalmeasure of the fracture frequency per unit volume. Spacing, dipand trace length of fractures have been accounted for. Thebiases associated with the mapping method have also beenaccounted for (II).</p><p>The correlation between impact-induced fracturing andelectric resistivity in crystalline rocks in the Lockne Areashows that the extent of impact fracturing in crystalline rockscan be measured with electro-magnetic or electric techniques.In addition the electric resistivity of crystalline basementand impact generated Tandsby Breccia from the Lockne Craterwere determined (I).</p><p>The relation between fracture frequency and electricresistivity in fresh water conditions using the VLF-R method isestablished from data collected from both two drill holes andfrom numerous outcrops in the Björkö region. Apreliminary quantification of the fracture frequency has beenmade. The MT resistivity models, related to the two drillholes, show that porosity and mineral-conductivity variationsof the bedrock affect this relation more than the salinityvariations in the bore-hole fluid. Further research is neededto establish a firm relation between fracture frequency,salinity of rock fluid, conductivity and porosity in order tovalidate the MT resistivity models (III).</p><p><b>Keywords:</b>Electric resistivity, Fracture frequency,Impact generated fractures, Electro-magnetic techniques, VLF-Rmethod, MT method, Window-mapping technique, Three-dimensionalfracture calculations, heat-exchange structure, geothermalenergy.</p>

Dans la région de Dimbokro-Bongouanou (Centre Est de la Côte d'Ivoire), l'alimentation en eau des populations se fait essentiellement au moyen de puits et forages. Ceux-ci ont été implantés dans les aquifères du socle au cours des différentes campagnes d'hydraulique villageoise mises en place dans ce secteur. L'analyse du taux de réussite et de la productivité de ces forages montre que leur implantation n'a pas toujours été optimale. Afin d'optimiser l'implantation de nouveaux forages, il semble donc nécessaire et primordial de caractériser l'hydrodynamique du socle fracturé. A cette fin, la présente étude procède d'abord à une caractérisation géologique puis hydrogéologique de la région de Dimbokro-Bongouanou. Ensuite, sont élaborés des modèles conceptuels géologiques et hydrogéologiques, qui décrivent la structure de l'aquifère et précisent les propriétés hydrodynamiques de ses différentes couches composites. Ces modèles géologiques et hydrogéologiques permettent de simuler numériquement l'écoulement régional. La caractérisation géologique de la région de Dimbokro-Bongouanou est basée sur une description des différentes formations géologiques de la région ; des hypothèses sur leur mise en place et les cycles d'érosion et d'altération qu'elles ont subis ; et une cartographie des discontinuités régionales par photo-interprétation d'image Radar rehaussée par la technique de filtrages adaptatifs. Les discontinuités identifiées sur l'image rehaussée sont validées à partir d'informations géologiques (données de fracturation mesurées à l'affleurement et données de fracturation relevées sur carte géologique).La caractérisation hydrogéologique de la région de Dimbokro-Bongouanou est basée sur la description des aquifères de la région et l'identification du rôle des discontinuités régionales dans les écoulements souterrains. La technique proposée à cet effet consiste à analyser les corrélations entre le débit des forages et leur distance au linéament le plus proche.Il est ainsi constaté que le débit des forages est inversement proportionnel à la distance à la discontinuité la plus proche. En d'autres termes, plus le forage est proche d'une discontinuité régionale, plus son débit est important. L'interprétation des lithologs, des données géologiques à l'affleurement et des données de résistivités électriques permet de proposer un modèle conceptuel géologique représentatif du profil d'altération type pour chaque domaine géologique de la région. En particulier, le modèle proposé décrit la structuration verticale du profil d'altération pour les trois principales formations géologiques de la région: les granites, les métasédiments et les métavolcanites. La caractérisation de la structure de l'aquifère permet ensuite de proposer un modèle conceptuel hydrogéologique pour chacun des profils d'altération basé sur l'analyse statistique des arrivées d'eau et de l'interprétation des données d'essais par pompage de différents forages. Cela permet d'identifier pour chaque formation les profondeurs de fréquence, de densité et de débit des arrivées d'eau ainsi que les couches du profil associées aux zones de conductivité et de productivité (débit spécifique) élevées.L'ensemble de ces informations géologiques et hydrogéologiques permet de proposer une modélisation conceptuelle de l'hydrosystème étudié (une partie du Bassin du NZI,environ 6300km2) ainsi qu'une modélisation numériques de l'écoulement, celle-ci servant de base à une réflexion sur la pertinence de l'information disponible et d'une modélisation discrète dans ce type d'environnement au vu des objectifs affichés (modèle de gestion et d'aide à la décision pour l'implantation de nouveaux forages). / The hydraulic characterization of fractured basement in Dimbokro-Bongouanou region, Côte d'Ivoire, is an essential step to achieve an optimization of new well locations, in terms of success rates and productivity.To this end, this study first proposes conceptual models of weathering profile for the three main geological formations of the region: granites, metasediments and metavolcanic rocks. Based on in-situ observations, interpretations of lithology and cycles of erosion and alteration, the typical weathering profiles are proposed for each type geological. These are formed from top to bottom of layers alloterite, isalterite, fissured and fractured fresh basement. The fissured layer shows the maximum density of fractures in the metavolcanic rocks and métasédiments, while the fractured fresh basement concentrates the highest density of fractures in granites. Moreover, interpretation of data from pumping tests conducted in various hydraulic programs indicate that the productivity of wells is not proportional to the depth due to variation, at region scale of the thickness of the fissured layer and fractured fresh basement which totalize the maximum of water arrivals. The spatial variation of hydraulic conductivity and productivity (specific rate) is influenced by the thickness of the fissured layer, alloterite layer of the weathering profile and topography. The regional fractures of the fractured fresh basement are also areas of high productivity, as evidenced by the negative correlation between rate of productive wells and distance to these fractures. A methodology of regional fractures mapping from the use of a Radar image and hydrogeological data is suggested.All of these geological and hydrogeological informations are finally integrated into a flow model and the simulated groundwater levels are compared with measured piezometric. It thus appears that the values of hydraulic conductivities deduced from pumping tests are 103 times lower than those that reproduce the regional flow. In addition, a dual approach (equivalent continuum for alterite layer and fissured layer vs. discrete fracture of the base) confirms the role of accidents in the regional flows.

Locality Mokrsko-west is located inside the Josef mining gallery and belongs to the ore district Psí Hory Mountains, known for its high content of micro-granular gold (~ 100 g/t). It is situated within the apophysis of Sázava tonalite, which is a part of Central Bohemian Plutonic Complex, located southerly from Prague. Besides other structural elements, the whole locality contains the network of sheeted quartz veinlets, which is the aim of this thesis. Data from vectorization and image analysis of the photographic documentation from the gallery and electron microscope has been used. The statistical approach has been used to quantify proportions of mineral phases within the quartz veinlets, their cumulative spacing and fractal distribution. Image analysis confirmed the presence of K-feldspathic metasomatism which affects the plagioclase grains. It forms rims on the edges of the quartz veinlets. The proportional relationship of K-feldspar and quartz within the veinlets wasn't confirmed. It's therefore possible that they were two separate processes of the uncertain time relation. Transfer from the lognormal distribution in histograms of vein spacing in drill-cores to the more normal distribution of the veinlets in the gallery walls was observed. Results from the cumulative spacing analysis confirmed...

Dans le cadre des opérations de perçage, les billettes en acier subissent un réchauffage de la température ambiante à une température d’environ 1250°C. Au cours de ce réchauffage, le gradient de température dans les billettes entraîne la détérioration de la santé axiale de celles-ci et est à l’origine de l’apparition de défauts sur le tube formé. Une méthodologie d’analyse des mécanismes à l’origine de ces défauts a été mise en place. Elle se base sur la caractérisation de la santé axiale par essais rhéologiques permettant d’établir des indicateurs de ductilité et par des examens métallurgiques identifiant les défauts internes.L'étude de la sollicitation thermomécanique induite par le réchauffage du produit est analysée à l’aide de simulations numériques par éléments finis et les zones de sollicitations critiques associées au procédé sont identifiées. La caractérisation des anomalies observées sur les billettes est ensuite faite à partir d’essais de fissuration et de simulations numériques X-FeM. L’implémentation d’un critère de rupture en contrainte dans la simulation du cycle de chauffe a permis de définir les valeurs de gradient thermique limite et les courbes de chauffe optimales. Les analyses montrent que les conditions de chauffe en début de cycle thermique ont une forte influence sur la santé axiale des billettes. Les résultats de ces travaux conduisent à des solutions concrètes pour l’amélioration de la productivité. / As part of the piercing operations, billets undergo a reheating process from room temperature to a temperature of about 1250°C. During this heating, the thermal gradient in the billet leads to a deterioration of the axial health and is responsible of the initiation ofdefects on the formed tube.A methodology for the analysis of the mechanisms at the origin of these defects has been established. It is based on first, the characterization of the axial health with hot rheological tests to establish some indicators of ductility and second, on metallurgical analyses to identify the internal defects.Then finite element simulations have been performed to study the thermo-mechanical loadings induced by heating. Critical solicitation zones of the product during the processes have been identified.Finally a characterization of the observed defects into the billets has been led coupling cracks growth tests and X-FeM numerical simulations. The implementation of the experimental stress failure criterion, in the simulation of the heating cycle allows to obtain good values of thermal gradient boundary curves and leads to optimal heating curves.The analysis shows that the conditions at the beginning of the reheating process have a strong influence on the axial health of the billets. The results of these studies lead to friendly industrial solutions for improving productivity.

Foi realizado estudo prospectivo com o objetivo de se determinar a ocorrência de traumatismo raquidiano (TR) em 355 doentes em coma decorrente de traumatismo cranioencefálico (TCE) resultante de acidente de tráfego atendidos no Pronto Socorro de Neurocirurgia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (PSNCHCFMUSP) de 1° de setembro de 2003 a 31 de dezembro de 2009. Todos os doentes foram submetidos ao exame físico e neurológico e à tomografia computadorizada (TC) do corpo inteiro para diagnosticar-se e avaliar-se a gravidade das lesões traumáticas encefálicas, vertebrais ou de outras regiões no momento da admissão ao PSNCHCFMUSP. Em 69 (19,4%) doentes, foi(ram) diagnosticada(s) lesão(ões) na coluna vertebral com o exame de TC da coluna vertebral. As idades dos doentes variaram de 12 a 55 anos (média de 29,0 anos). Eram do sexo masculino 57 (82,6%) doentes. As causas do(s) traumatismo(s) foi(ram) acidente(s) envolvendo motocicleta em 28 (40,6%) casos, atropelamento em 21 (30,5%), colisão de automóvel, caminhão ou caminhonete, em 18 (26,1%) ou acidente com bicicleta em dois (2,9%). Hemorragia subaracnóidea traumática foi a anormalidade intracraniana traumática mais evidenciada no exame de TC do crânio; ocorreu em 57 (82,6%). O(s) processo(s) transverso(s) foi(ram) o(s) segmento(s) vertebral(is) mais acometido(s) pela(s) fratura(s). A sétima vértebra cervical foi a mais lesada; nela identificaram-se fraturas em 24 (34,8%) doentes. Evidenciou-se que a distribuição das fraturas foi similar ao longo das demais vértebras da coluna cervical, quatro primeiras vértebras torácicas e vértebras lombares. Em oito (11,6%) doentes a(s) lesão(ões) neurológica(s) foi(ram) classificada(s) como Frankel A, e nos demais 61(88,4%), como Frankel não-A. Houve necessidade de cirurgia espinal em 24 (34,8%) doentes e de neurocirurgia craniana em 18 (26,0%) doentes. A Escala de Recuperação de Glasgow foi aplicada para avaliar-se as condições neurológicas do doente no momento da alta hospitalar e revelou ocorrência de óbito em dois (2,9%) doentes. Concluiuse que é recomendada a avaliação clínica e também com métodos de imagem da coluna vertebral nos doentes em coma decorrente de TCE / The author presents a prospective study aiming the evaluation of coexistence of spinal injury (SI) in 355 patients presenting coma due to craniocerebral trauma assisted at the Emergency Room of the Hospital das Clínicas of the University of São Paulo Medical School, from September, 1st, 2003 to december, 31th,2009. All patients underwent physical and neurological examination and had computed tomography (CT) scanning of the entire body to diagnose and evaluate the severity of brain and spinal injury at the time of admission. Traumatic lesions of the spine were diagnosed in 69 (19.4%) patients. The ages of patients ranged from 12 to 55 years (mean = 29,0 years).The SI predominated in males, corresponding to 57 (82.6%) patients. The causes of the trauma were motorcycle accident in 28 (40.6%) cases, running over in 21(30.5%), car collision 18 (26.1%) cases and bicycle accident in two (2.9%). Traumatic subarachnoid hemorrhage was the most common traumatic intracranial abnormality in the CT images; it was identified in 57 (82.6%) patients. The transverse process was the most common vertebral part presenting fracture(s). The 7th cervical vertebra was individually the most commonly affected; traumatic lesion of this vertebra presented in 24 (34.8%) patients. The diagnosis of fracture(s) was similar in the other cervical vertebrae and occurred also in the first four thoracic and in the lumbar vertebrae. Severe neurological deficit secondary to spine fracture was diagnosed in eight (11.6%) patients, classified as Frankel A. The others 61(88.4%) patients did not present complete spinal cord or spinal roots neurological deficits were classified as Frankel non A. The Recovery Scale of Glasgow was used to evaluate the neurological status at discharge from hospital. Two (2.9%) patients died. Spinal surgery was necessary in 24 (34.8%) patients and cranial surgery in 18 (26.0%). It was concluded that in addition to clinical evaluation, the CT imaging of the spine is recommended in patients in coma due to mechanical traumatic head injury

INTRODUÇÃO: As infecções osteoarticulares permanecem como um grande desafio para os profissionais de saúde envolvidos no seu manejo, a despeito do sucesso obtido com a introdução dos antimicrobianos para o tratamento das doenças infectocontagiosas no final da década de 1930. O Staphylococcus aureus (S. aureus) é o agente mais frequentemente encontrado nestas infecções e também é o agente mais estudado, porém possuímos poucas informações disponíveis na literatura médica a respeito das osteomielites por bacilos Gram-negativos (BGN). OBJETIVOS: A caracterização clínica e microbiológica dos episódios de osteomielite causadas por bacilos Gram-negativos. A determinação das diferenças evolutivas e dos fatores de risco para a ocorrência de osteomielite por bacilos Gram-negativos, quando comparadas à osteomielite causada por S. aureus. MÉTODOS: Análise retrospectiva dos casos de osteomielite causadas por bacilos Gram-negativos atendidos no Instituto de Ortopedia e Traumatologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo no período de janeiro de 2007 a janeiro de 2009. Apenas amostras de osso ou aspirado de canal medular foram consideradas válidas. RESULTADOS: Foram incluídos 89 pacientes no grupo S. aureus e 101 pacientes no grupo BGN. Os pacientes do grupo BGN eram predominantemente do sexo masculino (63%), com mediana de 42 anos de idade. Apresentaram-se com osteomielite crônica (43%) e osteomielite aguda associada à fratura exposta (32%), nos membros inferiores (71%), cuja principal sintomatologia inicial foi a fistulização (69%). Quando comparado ao grupo S. aureus, o grupo BGN estava estatisticamente associado com o antecedente de fratura exposta (35% vs. 18%; p=0,0064), apresentando ainda um maior tempo de internação hospitalar (mediana 41 vs. 24 dias; p=0,0114), maior tempo para a obtenção da primeira cultura positiva (mediana 10 vs. 6,5 dias; p=0,0042), antibioticoterapia mais prolongada (mediana 40 vs. 24 dias; p=0,0329), maior número de procedimentos cirúrgicos (média 3,41 vs. 2,47; p=0,0173) e maior uso de reparo do revestimento cutâneo (31% vs. 9%; p=0,0005). O grupo S. aureus estava estatisticamente associado com as osteomielites da coluna vertebral (23,6% vs. 6,9%; p=0,0008). Foram isolados 121 agentes Gram-negativos de 101 amostras clínicas e os agentes mais frequentes foram Enterobacter spp. (24,7%), Acinetobacter baumannii (21,4%), Pseudomonas aeruginosa (19,8%) e Klebsiella pneumoniae (8,2%). CONCLUSÕES: Os 101 pacientes portadores de osteomielite por BGN eram na sua maioria jovens, do sexo masculino, vítimas de traumas nos membros inferiores e que desenvolveram osteomielite aguda e crônica associadas a fraturas expostas. Os pacientes do grupo BGN necessitaram de um número maior de procedimentos cirúrgicos, maior uso de reparo do revestimento cutâneo, permaneceram internados por mais tempo, necessitaram de um número de dias maior para o isolamento do agente infeccioso e utilizaram antibioticoterapia mais prolongada, quando comparados aos pacientes do grupo S. aureus. O antecedente de fratura exposta foi o principal fator de risco para o desenvolvimento de osteomielite por um BGN, quando comparado ao grupo S. aureus / INTRODUCTION: Bone and joint infection remains a serious therapeutic challenge, despite the high success rate observed with antibiotic therapy in most bacterial disease since the end of 1930 decade. Staphylococcus aureus (S. aureus) is the most studied and the most frequently isolated pathogen, but there is insufficient information in medical literature regarding Gram- negative bacilli (GNB) osteomyelitis. OBJECTIVES: Describe clinical and microbiological characteristics of Gram-negative bacilli osteomyelitis. Establish evolving differences and risk factors for the occurrence of GNB osteomyelitis, compared to S. aureus osteomyelitis. METHODS: Retrospective analysis of all patients with GNB osteomyelitis treated at Institute of Orthopedics and Traumatology, Hospital das Clínicas - School of Medicine, Universidade de São Paulo from january 2007 to january 2009. Only bone or bone marrow aspirate samples were included. RESULTS: 89 patients were included in S. aureus group and 101 patients were included in GNB group. Patients in GNB group were mostly male (63%), with median age of 42 years. At presentation, they had chronic osteomyelitis (43%) and acute open-fracture associated osteomyelitis (32%), in the lower limbs (71%), with a discharging sinus as the main clinical sign (69%). When compared to S. aureus group, GNB group was statistically associated with a previous history of open-fracture (35% vs. 18%; p=0.0064), showed a longer length of hospital stay (median 41 vs. 24 days; p=0.0114), a higher number of days to isolate the infective bacteria (median 10 vs. 6,5 days; p=0.0042), a longer use of antibiotics (median 40 vs. 24 days; p=0.0329), a higher number of surgical procedures (mean 3,41 vs. 2,47; p=0.0173) and a higher rate of soft- tissue reconstruction (31% vs. 9%; p=0.0005). S. aureus group was statistically associated with spine osteomyelitis (23,6% vs. 6.9%; p=0.0008). 121 Gram-negative pathogens were isolated from 101 clinical samples and the most frequent agents were Enterobacter spp. (24.7%), Acinetobacter baumannii (21.4%), Pseudomonas aeruginosa (19.8%) and Klebsiella pneumoniae (8.2%). CONCLUSIONS: Patients with GNB osteomyelitis were mainly young, male, with lower limb trauma and developed chronic and open- fracture associated osteomyelitis. Patients in GNB group had a higher number of surgical procedures, a higher rate of soft-tissue reconstruction, a longer length of hospitalization, a longer time to isolate the infective bacteria and a prolonged use of antibiotics, when compared to patients in S. aureus group. A previous history of open-fracture was the main risk factor to development of GNB osteomyelitis, compared to S. aureus group

O presente estudo analisou os efeitos da fratura de côndilo unilateral, no período de crescimento. Para tanto, foram utilizados 50 ratos jovens, linhagem Wistar, com peso até 100g. Sob anestesia geral foi realizada no grupo experimental fratura do processo condilar no lado direito com desvio e no grupo controle-operado, foi feito apenas acesso cirúrgico ao côndilo. O sacrifício dos animais foi feito aos três meses de idade. A mandíbula foi desarticulada sendo obtidas as incidências radiográficas axial do crânio seco e lateral das hemi-mandíbulas. Foram feitas mensurações cefalométricas por meio de um sistema de computador. Foram aplicados os testes estatísticos “t" de Student entre os grupos e teste “t" de Student para dados pareados entre os lados, dentro de cada grupo.Houve diferença significante entre os grupos para o lado direito no comprimento das porções anterior (p=0,001) e posterior (0,017) da maxila e altura do ramo mandibular (p=0,001). Houve diferença significante entre os lados para o comprimento da mandíbula (p<0,001) e altura do ramo mandibular (p<0,001), nos grupos experimental e controle-operado. Houve diferença significante para a altura do corpo mandibular (p=0.001) e para o comprimento das porções anterior (p=0,002) e posterior (p=0,001) da maxila apenas no grupo experimental. Os resultados obtidos permitiram concluir que uma fratura de côndilo mandibular experimental durante o período de crescimento em ratos levou a uma assimetria da mandíbula na altura do corpo mandibular, com conseqüências também para a maxila. / The present study analyzed the effects of the condyle fracture were analyzed in the growing period in this study. Fifty young Wistar rats weighting 100g were used. Under general anestesia fracture of the condilar process on the right side with deviation was performed in the experimental group, while only the made surgical access was performed in the sham-operated group. The animals were sacrifized with three months of age. The mandible was disarticulated, and radiographic projections axial of dried skull and lateral of the hemimandible were obtained. Cephalometric mensurations through a computer system were made. Statistical tests "t" of Student between the groups and paired test "t" of Student among the sides, inside of each group were applied. There was a significant different among the groups to the right side in the length of the anterior portion (p=0,001) and posterior (0,017) of the maxilla and height of the mandibular ramus (p=0,001). There was significant difference among the sides for the length of the mandible (p <0,001) and height of the mandibular ramus (p<0,001), in the height of the body mandibular (p=0.001) and for the length of the anterior portions (p=0,002) and posterior (p=0,001) of the maxilla just in the experimental group. The obtained results allowed to conclude that a experimental fracture of mandibular condyle during the growing period in rats induced an asymmetry of the mandible in the height of the mandibular body, with also consequences to the maxilla.

Foi analisada a parte trabecular do colo do fêmur de 13 pacientes do sexo feminino, com idade acima dos 60 anos, com o método da histomorfometria óssea. Sete destas pacientes tiveram fratura do colo do fêmur. Todas foram submetidas a artroplastia do quadril. O exame de densitometria óssea não mostrou diferença significativa. Na espessura média das trabéculas não houve diferença significativa, porém o número de trabéculas foi menor e a separação entre elas foi maior no grupo com fraturas. / A histomorphometry evaluation of the trabecular part of the femoral neck was performed in 13 women over 60 years old submitted to hip arthroplasty. Seven of these patients had a femoral neck fracture. The bone mineral density showed no difference between both groups. The average thickness did not have significant between both groups, but the trabecular separation was higher and the number of trabecular bone was lower in the fracture group.

Introdução: O papel protetor da obesidade sobre a saúde óssea tem sido questionado, uma vez que a gordura visceral apresenta um efeito deletério sobre o osso. No entanto, até o momento, não existem estudos que avaliaram a associação entre a gordura visceral medida por absorciometria por dupla energia de raios X (DXA) com o risco de fraturas. Objetivo: Investigar a associação entre gordura visceral medida por DXA e incidência de fraturas não vertebrais em mulheres idosas da comunidade. Métodos: Este estudo de coorte longitudinal prospectivo de base populacional avaliou 433 mulheres com 65 anos ou mais. Um questionário clínico, incluindo história pessoal de fratura não vertebral por fragilidade foi realizado na avaliação inicial e após um tempo médio de seguimento de 4,3 anos. Todas as fraturas incidentes durante este período foram confirmadas por radiografia da região afetada. O tecido adiposo visceral (VAT) foi medido na região androide por DXA de corpo total através de um software específico. Modelos de regressão logística foram utilizados para avaliar a associação entre gordura visceral e fraturas não vertebrais. Resultados: A média de idade era de 72,8 ± 4,7 anos e 28 fraturas não vertebrais osteoporóticas foram identificadas após um período médio de seguimento de 4,3 ± 0,8 anos. De acordo com a classificação de Lipschitz para o estado nutricional de idosos, 38,6% das mulheres eram não obesas (IMC <= 27 kg/m²) e 61,4% foram consideradas como sobrepeso/obesas (IMC > 27 kg/m²). Após o ajuste para idade, raça, fratura prévia e densidade mineral óssea (DMO), o VAT (massa, área e volume) teve uma associação significativa com a incidência de fraturas não vertebrais apenas em mulheres idosas não obesas (VAT massa: OR 1,42, IC 95% 1,09-1,85, p = 0,010; VAT área: OR 1,19, IC 95% 1,05-1,36, p = 0,008; VAT volume: OR 1,40, IC 95% 1,09-1,80, p = 0,009). Conclusão: Este estudo sugere um efeito negativo da adiposidade visceral sobre a saúde óssea em mulheres não obesas. / Introduction: The protective effect of obesity on bone health has been questioned because visceral fat has been demonstrated to have a deleterious effect on bone. However, to date, there have been no studies evaluating the association between visceral fat measured by dual-energy Xray absorptiometry (DXA) with fracture risk. Objective: The aim of this study was to investigate the association of visceral fat measured by DXA with the incidence of non-spine fractures in community-dwelling elderly women. Methods: This longitudinal prospective population-based cohort study evaluated 433 community-dwelling women aged 65 years or older. A clinical questionnaire, including personal history of a fragility fracture in non-spine osteoporotic sites, was administered at baseline and after an average of 4.3 years. All incidences of fragility fractures during the study period were confirmed by affected-site radiography. Visceral adipose tissue (VAT) was measured in the android region of a whole-body DXA scan through a specific software. Logistic regression models were used to estimate the relationship between visceral fat and non-spine fractures. Results: The mean age was 72.8 ± 4.7 years, and 28 incident non-spine osteoporotic fractures were identified after a mean follow-up time of 4.3 ± 0.8 years. According to the Lipschitz classification for nutritional status in the elderly, 38.6% of women were nonobese (BMI <= 27 kg/m²) and 61.4 % were obese/overweight (BMI > 27 kg/m²). After adjusting for age, race, previous fractures, and bone mineral density (BMD), VAT (mass, area, volume) had a significant association with the incidence of non-spine fractures only in nonobese elderly women (VAT mass: OR 1.42, 95 % CI 1.09-1.85, p = 0.010; VAT area: OR 1.19, 95 % CI 1.05-1.36, p = 0.008; VAT volume: OR 1.40, 95 % CI 1.09-1.80, p = 0.009). Conclusion: This study suggests a potential negative effect of visceral adiposity on bone health in nonobese women