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Évaluation de la définition des fractures isolées de la hanche comme critère d'exclusion dans l'évaluation de performance des centres de traumatologieTiao, Judith 20 April 2018 (has links)
Les patients avec fracture isolée de la hanche (FIH) sont communément exclus des évaluations de la performance des centres de traumatologie. Cependant, il n’existe pas de définition standardisée des FIH pour les exclure. Nous avons conduit une revue systématique de la littérature afin d’évaluer s’il y avait consensus sur la définition d’une FIH. Le consensus était atteint si plus de 50 % des études utilisaient la même définition. Nous avons ensuite conduit une étude de cohorte rétrospective multicentrique pour évaluer l’influence de l’hétérogénéité dans la définition d’une FIH sur les évaluations de performance en traumatologie Le niveau d’accord entre le risque de mortalité ajusté de chaque centre selon les différentes définitions a été évalué avec le coefficient de corrélation de Pearson. Un coefficient ≥0,95 reflétait un accord acceptable1. Seulement 18 % des études de la revue ont utilisé la même définition. Les coefficients de corrélation entre définitions étaient tous supérieurs à 0,95. Il n’y a pas de consensus sur la définition d’une FIH utilisée comme critère d’exclusion dans les évaluations de performance des centres de traumatologie. Cependant, cette hétérogénéité n’a pas d’influence sur les résultats des évaluations de performance. / Patients with isolated hip fractures (IHF) are commonly excluded from trauma center performance evaluations. However, there is no standardized definition of IHF available. We performed a systematic literature review to evaluate whether there was consensus on the definition of IHF. Consensus was considered to be reached if over 50% of studies used the same definition. We then conducted a retrospective, multicentre cohort study to evaluate the influence of heterogeneity in IHF definitions on trauma center performance evaluations. Agreement between estimates of risk-adjusted mortality for each trauma center across definitions was evaluated with Pearson’s correlation coefficients. A coefficient above 0.95 was considered to represent acceptable agreement. Only 18% of studies in the review used the same definition of IHF. Correlation coefficients across definitions were all above 0.95. Results suggest that there is a lack of consensus on the most appropriate definition of IHF used as an exclusion criterion in trauma center performance evaluations. However, heterogeneity in definitions has little influence on the results of performance evaluations.
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Sex-Based Differences in Calcaneal Injury Tolerances Under High-Rate LoadingCeritano, Davide Walter 24 June 2020 (has links)
In this experiment, average calcaneal fracture force is measured across male and female groups. The purpose of this experiment is an analysis of alternatives exploring the importance of sex-based criteria in models representing injuries typical in underbody blast environments. Seventeen (17) right legs were harvested at the knee from cadavers representing three anthropometries: 50th percentile male (6), 75th percentile female (6), and 5th percentile female (5). Care was taken to preserve anatomically correct geometry as the legs were cut to equal lengths, the tibia and fibula were potted in Dyna-Cast®, flesh and ligaments were excised from the inferior surface of the calcaneus, and a small Dyna-Cast® pad was poured and sanded flat – interfacing with the exposed calcaneal surface. Each test specimen was mounted in a custom fixture and exposed once to high-rate axial loading characterized by a constant acceleration and 25.4mm intrusion, achieving an average speed of 4.7m/s (σ = 0.3m/s) in 10ms. Input acceleration was measured by an Endevco 7264c accelerometer and a Denton 2513 six-axis load cell measured reaction force proximal to the specimen. A VR Phantom v9.1 camera recorded x-ray imagery at 2k frames per second. Data were collected by a TDAS Pro data acquisition system at 20k samples per second and filtered in accordance with SAE J211. Time of fracture, established through x-ray imagery, was used to determined fracture force from the electronically synchronized load-cell data. 100% injury was recorded.
Average calcaneus fracture forces were reported as follows: 5406N (σ = 780N) for 50th percentile males, 4130N (σ = 1061N) for 75th percentile females, and 2873N (σ = 1293N) for 5th percentile females. Statistical significance was established between the reported averages according to three ANOVA tests: One-way (p = 0.0054), Brown-Forsythe (p = 0.0091), and Welch's (p = 0.0156). Unpaired Student's t-test confirmed significant differences between 50th percentile male vs 75th percentile female (p = 0.0469) and 50th percentile male vs 5th percentile female (p = 0.0030); the t-test did not show significance between the two female groups (p = 0.1315). Average impulse-to-fracture was calculated for each group and found to be not statistically significant. / Master of Science / A marked shift can be found in combat wound epidemiology towards a predominance of extremity injuries sustained from explosives. The Warrior Injury Assessment Mannequin (WIAMan) Project sought to develop a baseline dataset of post-mortem human surrogate responses to realistic explosive loading and correlate it to a highly instrumented mannequin for the further development of combat vehicles and personal protective gear. The following experiment exists within the WIAMan paradigm as an analysis of alternatives exploring the adequacy of the above mentioned baseline dataset in directly representing both male and female injuries. More specifically, this experiment interrogates the differences in average fracture forces between male and female calcanei across three anthropometries: 50th percentile male, 75th percentile female, and 5th percentile female.
Testing was carried out on 17 right cadaver legs cut to equal lengths, potted proximally in Dyna-Cast®, with the inferior surface of their calcanei exposed; a small Dyna-Cast® pad was poured for each calcaneus and sanded flat. Each test specimen was fixed to a Denton 2513 six-axis load cell proximally and exposed to a high-rate, constant acceleration, 25.4mm displacement aligned with the calcaneus along the long axis of the leg bones. Fracture time, established through x-ray images recorded at 2k frames per second with a VR Phantom V9.1 camera, was used to determine load cell force measurement at fracture.
Average calcaneus fracture forces were reported as follows: 5406N (σ = 780N) for 50th percentile males, 4130N (σ = 1061N) for 75th percentile females, and 2873N (σ = 1293N) for 5th percentile females. Statistical significance was established between the reported averages according to three ANOVA tests: One-way (p = 0.0054), Brown-Forsythe (p = 0.0091), and Welch's (p = 0.0156). Unpaired Student's t-test confirmed significant differences between 50th percentile male vs 75th percentile female (p = 0.0469) and 50th percentile male vs 5th percentile female (p = 0.0030); the t-test did not show significance between the two female groups (p = 0.1315). Average impulse-to-fracture was calculated for each group and found to be not statistically significant.
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The dark satanic mills: Evaluating patterns of health in England during the Industrial RevolutionBuckberry, Jo, Crane-Kramer, G. 12 October 2022 (has links)
Yes / Objective: this research seeks to investigate the impact the Industrial Revolution had on the population of England.
Materials: Pre-existing skeletal data from 1154 pre-Industrial (1066–1700AD) and 4157 industrial (1700–1905) skeletons from 21 cemeteries (N = 5411).
Methods: Context number, sex, age-at-death, stature and presence/absence of selected pathological conditions were collated. The data were compared using chi square, Kolmogorov-Smirnov, t-tests and logistic regression (α = 0.01).
Results: There was a statistically significant increase in cribra orbitalia, periosteal reactions, rib lesions, fractures, rickets, osteoporosis, osteoarthritis, enamel hypoplasia, dental caries and periapical lesions in the industrial period. Osteomyelitis decreased from the pre-industrial to industrial period.
Conclusion: Our results confirm the Industrial Revolution had a significant negative impact on human health, however the prevalence of TB, treponemal disease, maxillary sinusitis, osteomalacia, scurvy, gout and DISH did not change, suggesting these diseases were not impacted by the change in environmental conditions.
Significance: This is the largest study of health in the Industrial Revolution that includes non-adults and adults and considers age-at-death alongside disease status to date. This data supports the hypothesis that the Rise of Industry was associated with a significant decline in general health, but not an increase in all pathologies.
Limitations: This meta-analysis relies upon previously gathered data and diagnosis from a large number of researchers. Incomplete skeletons were often excluded from analyses. Few rural cemeteries were available for inclusion.
Suggestions for further research: Data from unpublished and ongoing excavations should be investigated. Comparison with historical data is encouraged. / Funded by the Royal Society (IES\R1\180138)
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Discrimination and Enhancement of Fracture Signals on Surface Seismic DataBansal, Reeshidev 13 June 2003 (has links)
Fracture patterns control flow and transport properties in a tight gas reservoir and therefore play a great role in siting the production wells. Hence, it is very important that the exact location and orientation of fractures or fracture swarms is known. Numerical models show that the fractures may be manifested on seismograms as discrete events.A number of data processing workflows were designed and examined to enhance these fracture signals and to suppress the reflections in seismic data. The workflows were first tested on a 2D synthetic data set, and then applied to 3D field data from the San Juan Basin in New Mexico.
All these workflows combine conventional processing tools which makes them easily applicable. Use of conventional P-wave data may also make this approach to locate fractures more economical than other currently available technology which often requires S-wave survey or computationally intensive inversion of data.
Diode filtering and dip-filtering in the common-offset domain yield good results and work very well in the presence of flat reflectors. NMO-Dip filter depends on the NMO velocity of the subsurface, but removes both flat and slightly dipping reflectors without affecting the fracture signals. Prior application of dip-moveout correction (DMO) did not make any difference on reflections, but included some incoherent noise to the data. The Eigenvector filter performed very well on flat or near-flat reflectors and left the fracture signals almost intact, but introduced some incoherent noise in the presence of steeply dipping reflectors. Harlan's scheme and Radon filtering are very sensitive with regard to parameters selection, but perform exceptionally well on flat or near-flat reflectors.
Dip-filter, Eigenvector filter, and Radon filter were also tested on 3D land data. Dip-filter and Eigenvector filter suppressed strong reflections with slight perturbations to the fracture signals. Radon filter did not produce satisfactory result due to small residual moveout difference between reflectors and fracture signals. / Master of Science
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Changement dans le risque fracturaire et le profil de fracture suivant la chirurgie bariatrique : étude de cohorte rétrospective utilisant les bases de données administratives de la RAMQRousseau, Catherine 03 May 2018 (has links)
La chirurgie bariatrique a des impacts positifs démontrés sur la santé cardiométabolique, sur la qualité de vie et sur la diminution de la mortalité, mais elle semble également affecter négativement l’intégrité osseuse. Bien que les études aient démontré un remodelage osseux augmenté, une perte de densité minérale osseuse et des altérations histomorphométriques suggestives d’ostéomalacie après la chirurgie bariatrique, peu d’études ont évalué son impact sur le risque fracturaire. Nos objectifs sont donc d’évaluer le risque fracturaire de patients ayant subi une chirurgie bariatrique comparativement aux contrôles obèses n’ayant pas subi de chirurgie et aux contrôles non-obèses, d’évaluer les sites fracturaires prédominants dans l’obésité et après la chirurgie bariatrique et de déterminer si le type de chirurgie bariatrique influence le risque fracturaire. Cette étude, réalisée grâce aux bases de données administratives de la Régie de l’assurance maladie du Québec (RAMQ), démontre que le risque fracturaire augmente avec le niveau d’obésité, que le profil de fracture se modifie après la chirurgie, passant d’un profil de fractures relié à l’obésité avant la chirurgie à un profil de type ostéoporotique en post-opératoire, et que la dérivation biliopancréatique est la seule chirurgie étant associée significativement à une augmentation du risque de fracture dans notre étude. / Bariatric surgery has proven beneficial effects on cardiometabolic health, on quality of life and on mortality, but it also seems to negatively influence bone health. Although studies have shown an increase in bone remodeling, a decrease in bone mineral density and histomorphometric alterations suggesting osteomalacia after surgery, few studies have evaluated its impact on fracture risk. Our objectives are to evaluate fracture risk in obese individuals who submitted to bariatric surgery compared with obese and non-obese controls, to evaluate fracture sites in obesity and after bariatric surgery, and to evaluate if the type of surgery influences fracture risk. This study, using healthcare administrative databases, showed that fracture risk increases with the level of obesity, that pattern of fracture changes after surgery, from a pattern associated with obesity before surgery to a pattern typical of osteoporosis post-operatively, and that biliopancreatic diversion is the only type of surgery that was associated with a significant increase in fracture risk in our study.
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L'axolotl : un modèle pour la régénération osseusePilote, Mireille January 2004 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
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Relations entre motif de fracturation et géodynamique dans les roches carbonatées : Importance du faciès de dépôt, de la diagénèse et des propriétés mécaniques de la roche / Relationships between fracture pattern and geodynamics in carbonates : Role of depositional facies, diagenesis and rock mechanical propertiesLavenu, Arthur 19 December 2013 (has links)
Caractériser les réseaux de fractures dans les réservoirs de subsurface est un challenge majeur. En effet, les fractures contrôlant en grande partie la perméabilité dans les réservoirs, il est nécessaire aujourd’hui d’en prédire l’organisation. Or, la prédiction des fractures en subsurface est difficilement contraignable du fait (1) de données limitées en termes de résolution (sismique), ou de continuité spatiale (imagerie de puits, carottes), et (2) d’un manque de compréhension des facteurs contrôlant la fracturation. Les analogues de terrain sont une bonne alternative aux données de subsurface, permettant d’accéder à la complexité du réseau de fractures, et aux hétérogénéités des carbonates en 3D. Pour chaque affleurement sélectionné, une étude pluridisciplinaire est réalisée, combinant géologie structurale, sédimentologie, diagenèse et pétrophysique. Ainsi, les conditions, le « timing » et les facteurs contrôlant la fracturation peuvent être précisés à travers l’histoire de l’encaissant carbonaté. La fracturation diffuse dans les carbonates est régie par (1) le faciès de dépôt qui contrôle les hétérogénéités mécaniques et la susceptibilité de la roche à la diagenèse, (2) la diagenèse que contrôle l’acquisition précoce du caractère cassant et l’inhibition de la fracturation tardive, et (3) l’enfouissement, responsable des variations de contraintes verticales et de l’apparition des fractures et stylolites. / Characterizing fracture networks in Naturally Fractured Reservoirs (NFR) is a major challenge for hydrocarbon exploration and production. Because fractures control most of the permeability through the reservoir, there is a necessity to predict their organization. However, at present-day, fracture prediction in the subsurface is poorly constrained because: (1) of limited data from seismic, well imaging and cores, and (2) of lack of understanding of controls on fracture occurrence. Outcrop analogues are good alternative to subsurface data for a full 3D fracture characterization. It enables to access the spatial complexity of fracture patterns, and to the 3D heterogeneities of carbonates. In each selected outcrop, a multidisciplinary approach has been undertaken, There, the conditions, timing and controlling factors on fracturing can be precised through the geodynamic history of the host carbonate. Diffuse fracturing in carbonates is governed by (1) the depositional facies which controls mechanical heterogeneities and rock diagenetic susceptibility, (2) the diagenesis which controls the early rock embrittlement and the late fracture inhibition, and (3) the burial, responsible for vertical stress variation and fracture–stylolite occurrence.
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Improving osteoporotic fracture prediction and identification of high risk individualsYang, Jingyan January 2019 (has links)
As the population ages, osteoporosis-related fractures represent a major and costly public health concern that is associated with increased morbidity and mortality in the United States, particularly in postmenopausal women [1]. A Surgeon General’s Reported has pointed out the importance of early diagnosis and appropriate treatment of bone diseases [2]. Treatment is typically indicated based on a bone mineral density (BMD) value of osteoporosis or a prior fragility fracture. Of note, many fragility fractures occur in postmenopausal women with non-osteoporotic BMD values. More significantly, a prior fragility fracture, particularly a prevalent vertebral fracture (VF), is a strong predictor for the elevated risk of subsequent fractures [3-7]. Hence, early identification of VFs is of great importance for initiating pharmacological therapy in women who may not otherwise be treated in order to prevent future fractures.
VFs are often subclinical which require additional efforts to identify these fractures [8]. Lateral dual-energy X-ray absorptiometry (DXA) scanning of the entire spine for vertebral fracture assessment (VFA) has been proposed by the International Society for Clinical Densitometry (ISCD) as an alternative of x-ray for the diagnosis of VFs [9]. Also, the National Osteoporosis Foundation (NOF) has provided guidelines when VFA should be performed [10]. However, the effectiveness of VFA as a screening tool for the identification of prevalent VFs is unclear and the cost-effectiveness of VFA is unknown, both limiting the implementation of VFA into routine care. Therefore, I conducted a systematic review and meta-analysis, the results of which have shown that the weighted pooled prevalence of VFA-detected VFs in asymptomatic women was 28%. Given that VFA is effective, I further evaluated the cost-effectiveness of VFA as a screening tool to reduce future osteoporotic fracture risk in U.S. postmenopausal women. The reference-case analysis has shown that VFA has the greatest cost-saving when the screening is initiated at age 65 years and with follow-up screening every 5 years. These findings support the NOF guidelines for the diagnostic use of VFA.
There are some women with increased risk for secondary osteoporosis who may not be eligible for BMD or VFA screening due to their younger age, for example, women with human immunodeficiency virus (HIV) infection. Therefore, an accurate fracture risk assessment tool is an important component in the management of bone health in HIV-infected women. The interests of validating the predictive accuracy of FRAX® (a widely accepted fracture risk prediction tool in general population [11]) arose from the reported poor performance of FRAX in older HIV-infected men [12]. I validated FRAX performance in HIV-infected women using the Women’s Interagency HIV study (WIHS), suggesting that FRAX also underestimated fracture risk in HIV-infected women, but improved with the addition of DXA parameters.
The results of the above studies demonstrate the potential role of VFA in reducing future fracture risk in women with prevalent VFs and the cost-effectiveness of incorporating VFA into routine screening for osteoporosis in postmenopausal women. Data were also provided for improving the fracture prediction in people with secondary osteoporosis using HIV infection as a model. These data may inform clinicians, policy makers and insurers on the benefit of including disease specific risk factors for fracture prediction and VF identification tools in the fight to prevent osteoporosis related fractures.
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L’actualité des traités chirurgicaux dans la Collection Hippocratique / The actuality of surgery essays in the Hippocratic CorpusDamas, Anny-France 18 June 2012 (has links)
Cette étude se doit d’analyser ce que les textes de la Collection hippocratique, ainsi que l’apport des commentateurs d’Hippocrate, tels Celse, Galien, et jusqu’aux chirurgiens actuels permettent de connaître de l’art chirurgical des Vème et IVème siècles avant J.-C., en Grèce. Les textes dits « chirurgicaux » sont ceux qui mentionnent un acte technique sur le corps humain, le plus souvent à l’aide d’un instrument « chirurgical ». Ils nous donnent des indications sur les pathologies traitées. Quelques documents iconographiques et quelques rares vestiges sont un apport intéressant. En confrontant les textes hippocratiques et la technique chirurgicale actuelle, nous verrons dans quelle mesure il est possible de reconstituer les conditions de réalisation de l’acte chirurgical par les praticiens hippocratiques. / The present study focuses on surgery procedures in fifth and fourth century B.-C. Greece. The analysis of these procedures is based on information stemming from the text constituting the Hippocratic Corpus as well as from Hippocrates’ commentators such as Celsus and Galen- and modern surgeons. The texts analyzed particularly those named “surgical “are those describing a manual intervention on the human body, most frequently supported by an instrument considered as “surgical.” They offer indications on the pathologies treated. Certain iconographic documents are of particular interest. The confrontation between Hippocratic texts and modern surgical techniques will enable to estimate the possibility of restitution of the surgical procedures’ conditions by the Hippocratic surgeons
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Craniofacial fracture patterns : a thesis submitted for the degree of Doctor of Medicine / Rodney D. CooterCooter, Rodney D. January 1990 (has links)
Typescript (Photocopy) / Bibliography: leaves 243-284 / 284 leaves : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (M.D.)--Dept. of Surgery, University of Adelaide, Dept. of Surgery, 1992
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