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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Development of an Evidence-Based Protocol for the Management of Acute Vertebral Fragility Fractures

Carey, Shannon De Ann 01 January 2017 (has links)
Vertebral fragility fractures are common, affecting approximately 50% of all postmenopausal women and 33% of men over the age of 50, and are the most common type of fracture seen in osteoporosis. The management of vertebral fragility fractures in the acute care setting is lacking in standardization, in the use of evidence-based practice, and in addressing the underlying cause of osteoporosis. The purpose of this project was to develop an evidence-based protocol to standardize the care of the vertebral fragility fracture in the acute care setting. This protocol included patient education, fall risk assessment, screening for osteoporosis, and follow up with an osteoporosis clinic for comprehensive management once discharged. This project used the Donabedian model to provide a conceptual framework for evaluating the structure, process, and outcomes related to the practice problem. This quantitative study involved 10 participants that were selected using purposive sampling and used process control charting to show compliance with elements of the guideline, and descriptive data to depict process change. Guideline compliance was measured over an 8-week period and indicated successful implementation of fall risk assessment with a 100% compliance rate and osteoporosis screening with an 80% compliance rate. Compliance with fracture education and securement of follow up were difficult to ascertain in the 8-week period and non-compliance evident. In conclusion, two elements of the guideline showed to be an unstable process and further work is necessary to improve. Positive social change may result from empowering nurses by education and giving them autonomy to use evidence-based practice to decrease the risk for secondary vertebral fragility fractures.
82

Impact de l'obésité sur la santé osseuse et l'incidence de fracture

Turcotte, Anne-Frédérique 09 April 2024 (has links)
Thèse ou mémoire avec insertion d'articles. / La fracture est un problème de santé publique majeur au Québec, au Canada, ainsi qu'à travers le monde. Elle est l'une des causes les plus fréquentes de perte d'autonomie et de morbidité dans la population, et peut entrainer des conséquences significatives sur la qualité de vie et le bien-être. En effet, la fracture peut être la source de douleurs aigues et chroniques, de perte de mobilité, d'incapacité physique voire d'un décès prématuré. De plus, des impacts psychologiques et sociaux peuvent survenir à la suite d'un événement fracturaire : la peur de subir une autre fracture ou de chuter, éprouver de l'anxiété ou de la dépression, vivre de l'isolement et la perception diminuée du rôle dans la société. L'obésité est un facteur de risque de fracture qui est encore peu connu et abordé en clinique, et pour lequel la prévention n'est pas mise de l'avant. En plus d'être associée au développement de nombreuses comorbidités, l'obésité a des effets néfastes sur le métabolisme osseux, affectant la densité et la qualité de l'os, ainsi que le risque de fracture. De plus, le risque de fracture pourrait être différent selon la mesure d'obésité utilisée. Considérant la hausse de la prévalence de l'obésité, il est nécessaire de mieux comprendre son impact sur la santé osseuse et le risque de fracture. Cela permettra d'identifier chez les individus avec obésité lesquels sont les plus à risque de fracture et de mettre en place des programmes ciblés de prévention des fractures. Le premier objectif de cette thèse était d'effectuer une revue systématique et méta-analyse sur les associations entre l'obésité et le risque de fracture, la densité minérale osseuse (DMO) et la qualité osseuse chez une population adulte. Plus spécifiquement, nous avons comparé l'incidence de fracture à tous sites et à des sites osseux spécifiques, la DMO à la hanche totale, au col fémoral, à la colonne lombaire, au radius et au tibia ainsi que certains paramètres de la qualité osseuse, comprenant la microarchitecture osseuse et des marqueurs de remodelage osseux, chez des hommes, des femmes préménopausées et des femmes ménopausées avec et sans obésité. Les principaux résultats de cette méta-analyse montrent que 1) le risque de fracture de la hanche est diminué chez les hommes et les femmes ménopausées ayant une obésité comparativement aux individus sans obésité, 2) le risque de fracture du poignet est diminué alors que celui de la cheville est augmenté chez les femmes ménopausées ayant une obésité, 3) les individus ayant une obésité ont une DMO plus élevée et une microarchitecture osseuse supérieure ou similaire aux individus sans obésité, et 4) les niveaux sanguins des marqueurs de remodelage osseux en obésité sont diminués ou similaires aux individus sans obésité. Cependant, plusieurs limites ont été notées incluant un manque d'études chez une population adulte plus jeune et évaluant certains sites spécifiques de fracture ainsi que l'hétérogénéité des études quant à la définition de l'obésité utilisée. Cette synthèse des connaissances a permis d'identifier les limites de la littérature actuelle et d'élaborer les questions de recherche subséquentes. Ainsi, nous avons ensuite étudié les relations entre l'obésité, définie selon l'indice de masse corporelle ou la circonférence de taille, et l'incidence de fracture à tous sites et à des sites squelettiques spécifiques (fractures ostéoporotiques majeures, membres inférieurs distaux et membres supérieurs distaux), en utilisant les données d'une cohorte prospective québécoise, la cohorte CARTaGENE. Plus précisément, cette étude visait à déterminer la forme des relations entre les deux définitions de l'obésité et le risque de fracture. Selon nos résultats, la relation entre la circonférence de taille et le risque de fracture est linéaire alors que celle entre l'indice de masse corporelle et le risque de fracture suit une fonction moins bien définie, représentée par une fonction spline cubique. De plus, nous avons démontré que le risque de fracture des membres inférieurs distaux augmente de façon linéaire en fonction de l'augmentation de la circonférence de taille, montrant l'importance de ne pas catégoriser les individus selon cette mesure. Afin de permettre une utilisation en clinique de ces résultats, nous avons voulu étudier si la circonférence de taille ajoute de l'information à l'IMC pour identifier les individus avec obésité à risque de fracture. Pour ce faire, nous avons évalué comme troisième objectif de cette thèse les relations entre la circonférence de taille et l'incidence de fracture à l'intérieur des catégories cliniques d'IMC, qui est la définition de l'obésité la plus utilisée en pratique. Nous avons également déterminé si l'IMC exerce un effet modifiant sur les relations entre la circonférence de taille et l'incidence de fracture. Notre étude a montré un risque de fracture des membres inférieurs distaux qui augmente linéairement en fonction de la circonférence de taille et ce, principalement chez les individus ayant un IMC normal ou en surpoids. Enfin, un effet modifiant de l'IMC sur les relations entre la circonférence de taille et le risque de fracture a été observé. En conclusion, les résultats obtenus à travers ces projets de doctorat soulignent la relation complexe entre l'obésité, le risque de fracture et la santé osseuse, qui diffère selon le sexe, le statut ménopausique, le site squelettique de la fracture et la définition d'obésité utilisée. De plus, nos études sont les premières à rapporter une relation linéaire entre la circonférence de taille et le risque de fracture dans une population adulte plus jeune. Elles ont permis d'approfondir les connaissances quant à l'impact de l'obésité sur le risque de fracture et la santé osseuse en 1) démontrant que l'obésité augmente principalement le risque de fracture des membres inférieurs distaux, peu importe la définition de l'obésité utilisée, 2) soulignant la valeur ajoutée de la circonférence de taille pour identifier chez les individus avec un IMC normal ou en surpoids ceux étant les plus à risque de fracture. D'autres recherches devront porter sur les mécanismes expliquant la fragilité osseuse à certains sites squelettiques des patients avec obésité (et principalement l'obésité abdominale) afin de développer des programmes de prévention des fractures adaptés à cette population. / Fractures are a major public health burden in Quebec, Canada, and worldwide. Fractures are a frequent cause of autonomy loss and morbidity in the population and can lead to substantial consequences on the quality of life. Indeed, fractures can cause acute and chronic pain, loss of mobility, physical disabilities, and premature death. Moreover, psychological and social consequences may occur following a fracture event, such as fear of sustaining another fracture or of falling, anxiety, depression, isolation and diminished perception of role in society. Obesity is a risk factor for fracture that is still under-recognized, barely addressed in clinical practice, and for which prevention is not present. In addition to being associated with the development of numerous comorbidities, obesity has detrimental effects on bone metabolism, affecting bone mineral density (BMD) and bone quality, as well as fracture risk. Moreover, fracture risk could differ depending on the definition of obesity used. Considering the increasing prevalence of obesity, it is necessary to better understand its impact on bone health and fracture risk. This will help identify among obese individuals those who are most at risk of fracture and implement targeted fracture prevention programs. The first objective of this thesis was to conduct a systematic review and meta-analysis on the associations between obesity and the risk of fractures, BMD, and bone quality in an adult population. Specifically, we compared the incidence of fractures at all sites and specific skeletal sites, BMD at the total hip, femoral neck, lumbar spine, radius, and tibia, as well as certain parameters of bone quality, including bone microarchitecture and serum markers of bone remodeling, in men, premenopausal women, and postmenopausal women with and without obesity. The main findings of this meta-analysis showed that: 1) the risk of hip fracture is decreased in men and postmenopausal women with obesity compared to individuals without obesity, 2) the risk of wrist fracture is reduced in postmenopausal women with obesity, while the risk of ankle fractures is increased, 3) individuals with obesity have a higher BMD and superior or similar bone microarchitecture compared to individuals without obesity, and 4) levels of serum bone remodeling markers in obesity are decreased or similar to individuals without obesity. However, several limitations were noted, including a lack of studies in a younger adult population and of studies that evaluated specific fracture sites, as well as heterogeneity in obesity definitions between studies. Nevertheless, this systematic review and meta-analysis helped identify the limitations of the current literature and develop subsequent research questions.Thus, we subsequently studied the relationships between obesity, defined by body mass index (BMI) or waist circumference, and the incidence of fractures at all sites and specific skeletal sites (major osteoporotic fractures, distal lower limbs, and distal upper limbs), using data from a prospective cohort from the province of Quebec, the CARTaGENE cohort. Specifically, this study aimed to determine the shape of the relationships between the two definitions of obesity and fracture risk. According to our results, the relationship between waist circumference and fracture risk is linear, while the relationship between BMI and the risk of fracture follows a cubic spline. Furthermore, we demonstrated that the risk of distal lower limb fractures increases linearly with increasing waist circumference, highlighting the importance of not categorizing individuals at risk of fracture based on this factor. To enable the clinical application of these findings, we then investigated whether waist circumference provides additional information to BMI in identifying individuals with obesity at risk of fracture.To achieve this, the third objective of this thesis was to evaluate the relationships between waist circumference and the incidence of fractures within clinical BMI categories, which is the most commonly used definition of obesity in practice. We also determined whether BMI exerts a modifying effect on the relationships between waist circumference and the incidence of fracture. Our study showed an increasing linear risk of distal lower limb fractures with increasing waist circumference, mainly among individuals with a BMI within the normal or overweight categories. Finally, a modifying effect of BMI on the relationships between waist circumference and the risk of fracture was observed. In conclusion, the results of these Ph.D. projects highlight the complex relationship between obesity, fracture risk and bone health, which varies according to sex, menopausal status, skeletal site, and the definition of obesity. Moreover, our studies are the first to report a linear relationship between waist circumference and fracture risk in a younger adult population. They have deepened our understanding of the impact of obesity on fracture risk and bone health by 1) demonstrating that obesity primarily increases the risk of distal lower limb fractures, regardless of the definition of obesity used, and 2) highlighting the added value of waist circumference in identifying individuals with a normal or overweight BMI who are at the highest risk of fracture. Additional research should focus on the mechanisms explaining bone fragility at specific skeletal sites in patients with obesity (and primarily abdominal obesity) to develop fracture prevention programs tailored to this population.
83

Submuscular bridge plating of length-unstable paediatric femoral shaft fractures in children between the ages of 6 and 13

Salkinder, Rael, Du Toit, J., Lamberts, R. P. 12 1900 (has links)
Thesis (MMed (Orth))--Stellenbosch University, 2014. / No abstract available
84

Semi-rigid composite plate fixation of tibial shaft fractures

Sohail, M. T. January 1984 (has links)
No description available.
85

The epidemiology of hip fractures in the elderly

Cooper, Cyrus January 1988 (has links)
No description available.
86

An investigation of lower limb venous function, whole blood coagulation and deep venous thrombosis following proximal femoral fracture

Wilson, Stanley Darrin January 1998 (has links)
No description available.
87

Cost effectiveness of alendronate to reduce hip fractures from osteoporosis in Icelandic postmenopausal women

Hauksson, Gudjon January 2012 (has links)
Thesis (M.S.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / Background: In 2001 an assessment tool for predicting fracture risk in postmenopausal women was developed. An index based on a small number of risk factors that are easily assessed was developed called the Fracture Index. The value of this index ranges from 0-13 with higher number associated with higher five year probability of fracture. The magnitude of the morbidity and mortality associated with osteoporosis makes it valuable for health care professionals to know if a treatment to prevent fractures is cost effective or not. Objective: To investigate at what Fracture Index value it becomes cost effective to treat postmenopausal women with alendronate to prevent hip fractures. The focus is on Icelandic women. Design: A Markov model was developed to model the disease progression for women 65 years of age to 85 years of age which is the average life expectancy for women in Iceland. Cost effectiveness of alendronate vs. no treatment was assessed by transitioning women in the model every six months between different health states. In the base-case five year treatment with alendronate was assumed. Results: At Fracture Index 1-2 the incremental cost effectiveness ratio (ICER) was 27,467,073 ISK (238,844$) which is not considered to be cost effective. At Fracture Index 3-4 the ICER was 4,349,2511SK (37,820$) which has a 59% probability of being cost effective if the per capita GOP (4,800,000 ISK) for Iceland is used as a threshold for cost effectiveness. However cost effectiveness for Fracture Index 3-4 depends largely on the assumptions made in the model, some of which are uncertain such as drug cost, drug efficacy and appropriate discount rate. Treatment with Alendronate is cost effective for Fracture Index 5 and variation in the model's assumptions does not change that result. Conclusions: The results of this study indicate that treating osteoporotic women with alendronate to prevent hip fractures becomes cost effective at Fracture Index 5 with a 1.9% five year probability of hip fracture. / 2031-01-01
88

Uso de DHS - dynamic hip screw - em fraturas instáveis do fêmur proximal : uma abordagem comparativa entre as deformações no fêmur normal e no fêmur com DHS

Ribeiro, Rita Elise Vaghetti January 2017 (has links)
O estudo fez comparações entre a intensidade e a distribuição das deformações a que fica submetido o fêmur proximal intacto e o fêmur proximal fraturado e implantado com o sistema parafuso deslizante Dynamic Hip Screw – DHS, em fraturas transtrocantéricas do tipo 31 - A2 – 2. Para isso, foram produzidas deformações, mediante carregamentos cíclicos, em fadiga. As amostras constituíram-se de ossos de fêmur sintéticos, intactos, e de ossos de fêmur sintéticos onde foram feitos cortes em laboratório produzindo situações de fratura do tipo 31 –A2.2. Nas amostras fraturadas foram colocadas as placas DHS simulando situações reais de osteossíntese. Os conjuntos de ossos mais placas foram então submetidos a ensaios de fadiga. Os resultados demonstraram que as presenças da fratura e do implante DHS alteraram a amplitude das deformações em todas as regiões do fêmur. Houve absorção da carga pelo implante DHS em todas as regiões de medição. Na região do colo femoral, o DHS absorveu 98% da carga, na região lateral 97%, no centro medial transversal 48%, no centro medial longitudinal 92%, no centro medial a 45 graus 94%, no calcar, antes da linha da fratura, 80%, na região do calcar, depois da linha da fratura, 81%, na região do segundo parafuso cortical transversal 81%, na região do segundo parafuso cortical longitudinal 73% e na região do segundo parafuso cortical a 45 graus 92%. A região do centro do pino guia e a região do segundo parafuso cortical foram as regiões de maior instabilidade mecânica. Para as condições de fratura do tipo 31 – A2.2 o implante do tipo DHS não absorve totalmente as deformações geradas, apresentando mobilidade do foco da fratura. Pequenas oscilações entre os ensaios causaram modificações importantes nos resultados, indicando que a relação ponto de medição ou a posição exata do implante podem implicar num desgaste ou afrouxamento prematuro do mesmo devido a uma sobrecarga. / The study compared the intensity and distribution of the deformations to the intact proximal femur and the proximal femur fractured and implanted with the slide screw system, Dynamic Hip Screw – DHS, in transtrochanteric fractures, 31 – A2 – 2 type. In this way, deformations were produced, by means of cyclic loads, in fatigue. The samples consisted of synthetic femoral bones intact and synthetic femoral bones that were cut in the laboratory producing fracture situations of type 31 – A2.2 type. In the fractured samples the DHS plates were placed simulating real osteosynthesis situations. The bone sets and plaques were then subjected to fatigue testing. The results showed that the presence of fracture and DHS implant altered the amplitude of deformations in all regions of the femur. The load was absorbed by the DHS implant in all measurement regions. In the femoral neck region, DHS absorbed 98% of the load, in the lateral region 97%, in the medial center – transverse – 48%, in the medial center – longitudinal – 92%, in the medial center – 45 degrees – 94%, in the calcar region, before the fracture line 80%, in the calcar region, after the fracture line, 81%, in the region of the second cortical screw – transverse – 81%, in the region of the second cortical screw – longitudinal – 73% and in the region of the second cortical screw – 45 degrees – 92% . The region of the center of the guide pin and the region of the second cortical screw were the regions of greater mechanical instability. For fracture conditions of type 31 - A2.2, the DHS type implant does not totally absorb the generated deformations, presenting mobility of the fracture focus. Small oscillations between the tests caused significant changes in the results, indicating that the relationship between the point of measurement and the exact position of the implant may lead to premature wear or loosening of the implant due to an overload.
89

Fracture-related diagenesis : a record of fluid flow through the Thamama Group, UAE

Al Blooshi, Mariam Nasser Abdulla January 2018 (has links)
Most of the hydrocarbon reservoirs in the world are carbonates, and most of these carbonate reservoirs are fractured. Fractures can form due to tectonic activity, mainly associated with fold and faults, and as a result of diagenesis. In many cases, the fractures in carbonates are cemented due to fluid flow, where these fluids precipitate cements. The presence of fractures can enhance reservoir fluid flow if the fractures were open and connected. This thesis focuses on carbonate reservoir fractures, and understanding the evolution of fluids from the cements that have precipitated within them. This thesis relates regional tectonic events to the formation of fractures, and of the environment and temperature of the fluids of precipitation in cement fractures the Early Cretaceous Thamama Group, in the United Arab Emirates (UAE). First, samples were studied from the subsurface in a highly faulted oil Field (A) located in South East Abu Dhabi. Core samples were taken from wells close to major faults in the field in both oil and water legs. Second, fractures in outcrop in Wadi Rahaba, Ras Al Khaima (RAK) in the Northern Emirates were studied where the Upper Thamama Group is exposed. The field study in the outcrop included the fracture orientation and cement types. The fractures in the outcrop were divided into two main generations, F1, (en-echelon) and F2 and they were both fully or partially cemented. The main tectonic events that affected the fracture formation in the Thamama Group are foreland autochthon in the Precambrian to Lower Cretaceous, a frontal triangle zone in Neogene and Dibba zone which consists of Hawasina units (Triassic to Cretaceous), and the Sumeini units (Lower to Middle Cretaceous). F1 is related to the NS orientation fracture system consistent to the Arabian Trend sets caused by Cenozoic compression. F2 is related to the EW orientation fracture system matching Tethyan extensional trend sets. Petrographic analysis of the subsurface thin sections revealed the presence of three main sets of fractures. Fracture Set 1 (cemented), Fracture Set 2 (open) and Fracture Set 3 (cemented, only in Lower Thamama). The fracture cement included equant and blocky calcite as well as saddle dolomite. Cathodoluminescence (CL) analysis assigned the number of cement zones in each cement type in the fractures, and revealed more cement zones in the Lower Thamama reservoirs than the Upper. The most important diagenetic events were cementation and dissolution, which took place towards the end of the paragenetic sequence. The reservoirs contained significant amounts of stylolites, dissolution seams and bitumen, which were associated with most of the dissolution events. mMg/mCa obtained from in situ elemental analysis showed variation through the calcite and dolomite cement zones in the different reservoirs of the Thamama Group. This was inferred to be due to temperature changes. The Upper Thamama Reservoirs (A, B, and C) show lower mMg/mCa (0.072-0.48) than the Lower Thamama reservoirs (F,G) (0,4-1.3), meaning that the Upper Thamama fracture calcite cements were precipitated at higher overall temperatures than the Lower Thamama reservoirs. Mn-Fe analysis allowed an understanding of the redox index through the different cement zones, in both Fracture Set 1 and Fracture Set 3. Analysis of Sr showed the absence of exotic fluids role in the diagenetic system. In-situ (SIMS) δ18OVPDB values were obtained for the calcite cementation history of the two fracture sets in the five reservoirs of the Thamama Group. The δ18OVPDB analysis indicated that Fracture Set 1 has a longer cementation history than Fracture Set 3, and has wider range of temperatures (58-128°C). A comparison of the outcrop analysis results and the subsurface reservoir was established at the end to distinguish the similarities and differences between the subsurface and outcrop in fracture types, fracture cement types and characteristics of the elemental analysis curve behaviours. The fracture cement in both subsurface and outcrop seemed to be precipitated at deep burial environment.
90

Effects of type-I collagen fractional composition and pyridinium crosslink content on cortical bone strength in the human femur

Rice, Michael Blair. January 2001 (has links)
Thesis (M.S.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains viii, 88 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 81-88).

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