Dissertations / Theses: 'Fractures, Open'

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Aird, J. "Human Immunodeficiency Virus and open fractures : is wound or fracture healing affected in surgically stabilised open fractures? : a prospective study." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1343913/.

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Background: 33 million people worldwide are infected with HIV, a complex disease that affects many of the processes involved in wound and fracture healing. There is little evidence available to guide acute management of open fractures in these patients and fears of acute and delayed sepsis often inhibit the use of surgical fixation, which may be the most effective way of achieving union. This study addresses the hypothesis that the presence of either HIV or advanced HIV (CD4 count <=350) leads to an increased risk of complications in patients with open fractures treated with surgical stabilization. South Africa has one of the highest rates of both HIV and high energy trauma in the world, so was deemed an appropriate place for the study of this interaction. Methods: This prospective observational study compared surgical fixation of open fractures in HIV positive and negative patients. 133 patients with 135 open fractures fulfilled the inclusion criteria. 86 fractures were in HIV negative and 33 in HIV positive patients. The remaining 16 patients refused HIV tests. 12 HIV positive patients had advanced disease (CD4 <=350), 14 had early disease (CD4 >350), 7 refused CD4 count testing. This cohort was three times larger (number of HIV positive patients) than any similar previously published study. There was no randomised allocation; the treatment of these patients was based on locally developed protocols and was dependent on; fracture type, location and the grade of wound. Patients were followed up either till union had been achieved or for 6 months in tibia/femur fractures, and 3 months in other fractures. The primary outcome was acute wound infection, secondary outcomes tested were fracture union and pin site sepsis. The analysis of the binary nominal data was done using the Chi squared test. In cases where the expected value was less than 5, then the Fisher’s exact test was used. In the assessment of multiple potential risk factors, binary logistic regression was used. Results: Analysis of background characteristics showed that HIV positive and negative populations were broadly similar with regard to demographics, injury type/location and grade of wound. In the analysis of the primary outcome, the risk of wound infection was marginally higher in patients without HIV (22%) as compared to patients with HIV (15%). This difference was small and did not reach statistical significance (n=135, Risk Ratio 0.7, p value 0.40). However, as hypothesized, the infection risk was higher in patients with advanced HIV (26%), compared to patients with early HIV (5%). The numbers, however, were small and this did not reach statistical significance (n=33, Risk Ratio=4.8, P value= 0.12). Sub group analyses, conceived prior to the study, provided strong evidence that patients with Gustilo Anderson grade 1 injuries had a higher risk of wound infection in patients with advanced HIV than controls (HIV negative and early HIV) (n=46, Risk Ratio=6.3, P value =0.02). Of note, departmental guidelines meant that patients with grade 1 injury were not prioritised for theatre and had, on average, a delay of 3.5 days to surgery. The average delay was similar in both HIV positive and negative groups. Analysis of the secondary outcome, nonunion, provided strong evidence that the risk of nonunion was higher in HIV positive than HIV negative patients (n=115, Risk Ratio=4.1, P value=0.04). Interestingly, the patients with advanced HIV had a slightly lower nonunion risk (13%) than patients with early HIV (20%). However the numbers were small and the difference was not statistically significant (n=33, Risk Ratio=0.8, P value=1). The incidence of nonunion was not correlated with the presence of wound infection. The risk of mild pin site sepsis in fractures treated with external fixation was similar in both HIV positive (60%) and negative (67%) patients (n=31, Risk Ratio=0.9, P value=1). An increased risk of severe pin site sepsis was noted in patients with advanced HIV (50%), compared to controls (25%). Although the difference is large, the numbers are small and the difference was not statistically significant (n=28, Risk Ratio=2, P value= 0.31). It would require 160 patients to prove a difference of this size. Conclusions: Data from this study appears to dispute the conclusion of previous studies that suggest that all patients with HIV are at higher risk of wound infection, and therefore internal fixation should be considered with caution. In this study it was only the patients with advanced HIV that showed a small increase in the risk of wound infection. Based on this study the author suggests that early HIV should not be a contraindication to either internal or external fixation in open fractures, due to concerns of wound infection. However, advanced HIV should continue to be considered a relative contraindication to internal fixation, until further data becomes available. Since this finding applied equally to grade 1 (Gustilo Anderson) injuries, the data suggests that any theatre delays in patients with advanced HIV may be detrimental to outcomes. This is contrary to published data that suggests that grade 1 injuries do not need to be prioritised. The data provides strong evidence that HIV leads to an increased risk of non unions. Interestingly, the risk of non union is less in patients with advanced HIV. This may fit with recently published laboratory studies suggesting that the absence of lymphocytes is beneficial to bone healing. Based on this evidence the author suggests that in patients with HIV treatment strategies should be aimed at achieving union, rather than on potentially unfounded concerns of preventing infection. In patients treated with external fixation, the data provides weak evidence of an increased risk of severe pin site sepsis in advanced HIV. This observation may be due to an increased susceptibility to infection, or to problems with bone healing in these patients. Based on this evidence, and the evidence that patients with HIV may be at increased risk of non union, the author suggests that HIV positive patients being treated with external fixators, should be considered for treatment strategies that will prolong the life of the pin bone interface. These may include additional pins, wires and/or the use of hydroxyapatite coated half pins.

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Nussbaum, Marcy Lauren. "Meta-Analysis of Open vs Closed Surgery of Mandibular Condyle Fractures." VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/1397.

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A review of the literature reveals a difference of opinion regarding whether open or closed reduction of condylar fractures produces the best results. It would be beneficial to critically analyze past studies that have directly compared the two methods in an attempt to answer this question. A Medline search for articles using the key words 'mandibular condyle fractures' and 'mandibular condyle fractures surgery' was performed. The articles chosen for the meta-analysis contained data on at least one of the following: postoperative maximum mouth opening, lateral excursion, protrusion, deviation on opening, asymmetry, and joint pain or muscle pain. Several common statistical methods were used to test for differences between open and closed surgery, including the weighted average method for fixed and random effects as well as the Mantel-Haenszel method for fixed effects. Some of the outcome variables were found to be statistically significant but were interpreted with caution because of the poor quality of the studies assessed. There is a need for more standardized data collection as well as patient randomization to treatment groups.

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Worlock, Peter Harrison. "The prevention of infection in open fractures : an experimental study of the effects of fracture stability and of antibiotic therapy." Thesis, University of Nottingham, 1986. http://eprints.nottingham.ac.uk/13676/.

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An experimental model of a contaminated open fracture has been developed in rabbits, using a reproducible midshaft fracture of the tibia. This model has been used to: 1) Test the hypothesis that stable fixation of an open fracture will reduce its susceptibility to infection. 2) Assess the effect of antibiotics on infection rate, with particular reference to the delay in administering the initial dose. The pattern of fracture healing was initially determined for stable and unstable fixation, without inoculation with bacteria. Fractures fixed with a dynamic compression plate ("stable" group) healed by primary bone union, while fractures stabilised with a loose-fitting intramedullary rod ("unstable" group) healed by external callus formation. Forty- one rabbits were used in the definitive study of the effect of stability. All fractures were inoculated with Staphylococcus aureus in a standard concentration. There were twenty rabbits in the stable group (compression plate) and osteomyelitis developed in seven (35%). Of the twenty- one rabbits in the unstable group (loose- fitting intramedullary rod), fifteen (71%) became infected. This difference in infection rate is statistically significant (p<0.02). The "rod- fixed fracture" model had the highest infection rate and was therefore used to study the effect of antibiotics. Fifty-one rabbits were used; a single intramuscular injection of cephradine was given to each animal at varying times in relation to inoculation with bacteria. Although the maximal reduction in infection rate was observed when the antibiotic was given before inoculation with bacteria, a 40% decrease in the infection rate was still seen when the antibiotic was given after bacterial inoculation. This effect persisted even if the initial dose of antibiotic was delayed four hours after inoculation. These findings support the concept of stabilisation of open fractures in man; and suggest that appropriate systemic antibiotics should be routinely used in the management of open fractures in man, even if the treatment is delayed up to four hours after injury.

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П`ятикоп, Геннадій Іванович, Геннадий Иванович Пятикоп, Hennadii Ivanovych Piatykop, Дмитро Володимирович Шищук, Дмитрий Владимирович Шищук, Dmytro Volodymyrovych Shyshсhuk, and Л. О. Самодахова. "Тактика лікування відкритих переломів кісток." Thesis, Вид-во СумДУ, 2005. http://essuir.sumdu.edu.ua/handle/123456789/7298.

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Boriani, Filippo <1977&gt. "The "Orthoplastic" combined surgical approach to open tibia fractures: a multicentric prospective outcome study." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6754/.

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Introduction: Open fractures of the leg represent a severe trauma. The combined approach, shared between plastic and orthopaedic surgeons, is considered to be important, although this multidisciplinary treatment is not routinely performed. Aim of this study was to verify whether the orthoplastic treatment is of any advantage over the traditional simply orthopedic treatment, through a multicentric inclusion of these unfrequent injuries into a prospective study. Material and methods: The following trauma centres were involved: Rizzoli Orthopaedic Institute/University of Bologna (leading centre) and Maggiore Hospital (Bologna, Italy), Frenchay Hospital (Bristol, United Kingdom), Jinnah Hospital (Lahore, Pakistan). All patients consecutively hospitalized in the mentioned centres between January 2012 and December 2013 due to tibial open fractures were included in the study and prospectively followed up to December 2014. Demographics and other clinical features were recorded, including the type of treatment (orthopaedic or orthoplastic). The considered outcome measures included duration of hospitalization, time for bone union and soft tissue closure, Enneking score at 3, 6 and 12 months, the incidence of osteomyelitis and other complications. Results: A total of 164 patients were included in the study. Out of them 68% were treated with an orthoplastic approach, whereas 32% received a purely orthopedic treatment. All considered outcome measures showed to be improved by the orthoplastic approach, compared to the orthopaedic one: time for soft tissue closure (2 versus 25 weeks), duration of hospital stay (22 versus 55 days), time for bone union (6 versus 8.5 months) , number of additional operations (0.6 versus 1.2) and functional recovery of the limb at 12 months (27 versus 19, Enneking’s score). All results were statistically significant. Conclusion: The combined orthoplastic approach to the treatment of open tibia fractures, in particular for high grade injuries (Gustilo 3B), is proven to improve the outcome of these severe injuries.

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Melin, Hanna. "Controlling parameters for normal and shear behaviour of rock fractures-a study of direct shear test data from SKB." Thesis, KTH, Jord- och bergmekanik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-93976.

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The deep mining and civil engineering industry need to perform rock stability analyses during excavation projects. The stability is mainly controlled by the shear strength of the rock fractures, which are the weakest point of the rock mass. In turn, the shear strength is governed by the mechanical properties of the fractures. It is both time and cost demanding to determine the properties of the rock fractures in laboratory. Also, the interpretation of the results requires a deep understanding of the normal and shear behaviour of rock fractures. This study aims to investigate if it is possible to determine the peak shear strength of rock fractures by merely estimating fracture parameters during field mapping and core logging. SKB supplied test results on drilled bore cores from site investigations in Forsmark and Laxemar for deep nuclear waste deposits. SKB generated data of high quality and in large quantity, which made it very valuable for the purpose of the study. The study begins with a literature review and an interaction matrix, clarifying the relationships between mechanical properties and affecting parameters of rock fractures. The predicted relationships of the parameters are then tested in an analysis based on the compiled data from SKB. The results show that the peak friction angle, the residual friction angle and the dilation angle are possible to approximate for open granite fractures in deep mining projects. Further on, the study proposes that the joint matching coefficient is included in the field mapping and core logging since it has a strong influence on the mechanical behaviour of the fracture, notably the normal and shear stiffness. Finally, the study questions estimations of JRC on small samples.

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Lanka, Gopi Krishna. "Stability of the Mandible–Strut Plate Complex in Isolated Angle Fractures: A Finite Element Study." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535382405124984.

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Barouni, Elyas. "Soft tissue Reconstruction of Gustilo-Anderson Grade IIIB Open Extra-Articular Tibial Fractures at a Tertiary Hospital in Cape Town, South Africa: A Retrospective Case Series." Master's thesis, Faculty of Health Sciences, 2020. http://hdl.handle.net/11427/32588.

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Introduction: Management of Gustilo-Anderson grade 3b tibia fractures are challenging due to the high rate of complications which includes infection, nonunion and possible amputation. Due to limited soft tissue coverage of the tibia antero-medially, open fractures remain a treatment challenge. Despite many advances, the ideal time delay to definitive soft tissue cover remains controversial. Aim: We aimed to investigate the management strategy and the outcome of soft tissue reconstruction of Gustilo-Anderson grade 3b tibia fractures at a tertiary hospital in Cape Town, South Africa. Methods: A retrospective study was conducted on 22 patients who underwent soft tissue reconstruction for grade 3b tibia fractures from January 2014 to July 2017. Patient demographics, comorbidities, injury characteristics and management practices such as time to debridement, relook time, Negative Pressure Wound Therapy (NPWT), soft tissue coverage and complications were recorded. Results: Most patients were males (n=18; 81.8%) with an average age of 39.3 years. Pedestrian vehicle accidents accounted for 45.4%(n=10), motor-vehicle accidents (n=6; 27.3%) and gunshot wounds (n=2; 9.1%). The commonest site of injury was the middle third of the tibia (n=13; 59.1%), distal third (n=7; 31.8%) and proximal third (n=2; 9.1%). Most patients (n=18; 81.8%) were debrided within 24 hours. The mean times for NPWT prior to cover was 12.5 days and for soft tissue cover 13.7 days (range 2-35), respectively. Fasciocutaneous flaps (n=11; 50%) were predominantly used as cover, then pedicled muscle flaps (n=8; 36.4%), free flaps (n=2) and skin graft(n=1). Most patients (n=13; 59.1%) received satisfactory outcomes. Seven (31.8%) required soft tissue revisions. Three patients (13.6%) suffered complications namely, complete flap loss resulting in amputation, partial skin graft loss and soft tissue infection, respectively. Patients who underwent debridement after 24 hours reported the least complications and there appeared to be better outcomes in the relooks beyond 48 hours. Conclusion: Despite achieving outcomes which concur with other published studies, the BOAST 4 guidelines were not fully reflected in our management strategy. We will require larger numbers in future studies to formulate a standardized management protocol going forward.

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Nemanja, Gvozdenović. "Rana prognoza kvaliteta života politraumatizovanih bolesnika sa prelomima dugih kostiju." Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2016. http://www.cris.uns.ac.rs/record.jsf?recordId=99961&source=NDLTD&language=en.

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Pod pojmom politraume se podrazumeva teška istovremena povreda najmanje dve regije tela sa anatomskom težinom povrede AIS koja je jednaka ili veća od tri kao i ukupna izračunata anatomska težina povreda izražena ISS zbirom mora da bude veća od 15. Cilj istraživanja je da se primenom upitnika (SF36, PTSD–testa i Glazgov skale ishoda) proceni kvalitet života između politraumatizovanih pacijenata sa prelomomima dugih kostiju i politraumatizovanih bez preloma duge kosti kao i da se uoče rani pokazatelji loše prognoze kvaliteta života nakon završetka lečenja. Istraživanje je prospektivnog karaktera i obuhvatilo je 202 politraumatizovana pacijenta koji su bili povređeni u periodu 2010-2014 godine i bili lečeni u Urgentnom Centu Kliničkog Centra Vojvodine. Od 202 politraumatizovana pacijenta na kontrolne preglede se odazvalo ukupno 72 pacijenta, 37 sa prelomima dugih kostiju - ispitivana grupa i 35 politraumatizovanih pacijenata bez preloma duge kosti koji su činili kontrolnu gupu. Godinu dana nakon završetka hospitalizacije svaki ispitanik je popunjavao upitnik( SF36, PTSD test i Glazgov skala ishoda ), načinjen je klinički pregled i standardna radiografija predela preloma duge kosti. Rezultati ukazuju da ukupni kvalitet života nakon završetka lečenja se ne razlikuje značajno između ispitivanih grupa, iako politraumatizovani sa prelomima dugih kostiju imaju niži kvalitet života, odnosno značajno lošije fizički funkcionišu i imaju značajno češće psihičke poremećaje (postraumatski stresni poremećaj, depresija) u odnosu na kontrolnu grupu. Tip preloma duge kosti nije uticao na krajnji kvalitet života politraumatizovanih, dok su oni sa dva i više preloma imali značajno lošiji kvalitet života. Na osnovu dobijenih rezultata konstatovali smo da veću šansu za bolji kvalitet života imaju pacijenti mlađi od 44 godine, ukoliko su inicjalno imali vrednost ISS skora manji od 30,5 bodova, vrednosti sistolnog i dijastolnog arterijskog pritiska u referentnim vrednostima, kao i broja eritrocita i trombocita, i ukoliko su primili manje od 4 jedinica transfuzije krvi u prva 24 časa.
The term of polytrauma means, a patient with multiple severe injuries in at least two regions of the body with anatomical severity of trauma AIS equal or greater than three and the total calculated weight anatomical injuries expressed by ISS score must be greater than 15. The aim of our study is early estimate of quality of life in polytrauma patients with multiple fractures of the long bones and polytrauma patients without fractures of long bones as well as to detect early indicators of poor prognosis of quality of life after treatment, using questionnaires (SF 36, PTSD test and Glasgow Outcome Scale). This was prospective study and included 202 polytrauma patients who were injured during the period 2010-2014 and were treated in the Emergency Center of Clinical Center of Vojvodina. From 202 polytrauma patients, on control examinations responded 72 patients, 37 with fractures of long bones - study group and 35 polytrauma patients without fractures of long bones and they were control group. One year after the end of hospitalization each patient filled out a questionnaire (SF36, PTSD test and Glasgow Outcome Scale), made a clinical examination and standard X-rays of long bone fractures. Our results indicate that the overall quality of life after treatment is not significantly different between the groups, although polytraumatized patients with fractures have a lower quality of life and significantly worse physical functioning and have significantly more mental disorders (post-traumatic stress disorder, depression) compared to the control group. Type of long bone fractures did not affect on the final quality of life, while those patients with two or more fractures had a significantly poorer quality of life. Based on these results we concluded that greater chance for a better quality of life have patients younger than 44 years, unless they had initially ISS score less than 30.5 points, systolic and diastolic blood pressure in the reference values as well as the number of red blood cells and platelets, and if they received less than 4 units of blood transfusions in the first 24 hours.

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Carvalho, Vladimir Cordeiro de. "Osteomielite por bacilos Gram-negativos: estudo comparativo das características clínico-microbiológicas e fatores de risco com as infecções por Staphylococcus aureus." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5140/tde-14082013-105434/.

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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

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Bass, Michael Kevin 1975. "Fully-plastic open-bend and back-bend fracture specimens." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/88831.

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Clotet, i. Fons Xavier. "Imbibition in a model open fracture. Capillary rise, kinetic roughening, and intermittent avalanche dynamics." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/284588.

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The dynamics of fractured media flows is relevant in many processes of interest that range from the micrometre to the kilometre lengthscales. Flow in disordered media has been proven to be an interesting system to study fundamental physics problems also. The goal of this Thesis is to study the spatio-temporal dynamics of the oil-air interface between displaced air and invading oil, in imbibition displacements through a model open fracture. The research combines exhaustive experimental work with accurate data analysis based on methods of nonlinear statistical physics. Imbibition is a process of fluid transport in a medium in which an invading fluid that preferentially wets the medium displaces the previously resident, immiscible fluid. According to the driving protocols we define spontaneous imbibition, in which the interface is driven at constant pressure difference between the inlet and the outlet of the medium and the flow rate is free to change in time, and forced-flow imbibition in which a constant flow rate of fluid is imposed at the inlet and the pressure difference may change in time. Our model open fracture consists of a Hele-Shaw (HS) cell, i.e. two parallel plates separated by a narrow gap spacing. Two configurations that mimic an open fracture have been explored: a flat HS cell, with constant aperture, and a HS cell with a dichotomic gap spacing randomly distributed in space (disordered cell). Silicone oils of different viscosities have been used as invading fluid. The advancement of the fluid front is recorded by using either CCD or CMOS cameras. An edge-tracking algorithm is applied to the binarized images to obtain front positions. We first study the evolution in time of the mean position of the interface in spontaneous imbibition experiments (capillary rise) through our two model open fractures. Experiments are performed with and without the presence of an effective gravity, achieved systematically tilting the cell against the advancement of the front or keeping it horizontal. Different pressure differences between the inlet and the outlet are systematically explored as well. We propose a new analytical solution for the spatially-averaged position of the imbibing front, based on a pressure balance equation, that reproduces experimental results at all times. In invasion of the disordered cell, capillary pressure and permeability variations distort imbibition fronts due to medium heterogeneities, while viscous pressure and surface tension tend to restore their flatness. As a result, the oil-air interface develops long-range correlations, with a lateral correlation length that depends on the capillary number Ca, tuned experimentally. Consequently, fronts advancing through the disordered cell are not flat during the whole experiment but get rough as the fluid penetrates the medium from an initially-flat interface to a final, statistically-invariant rough front. The kinetic roughening process, that occurs as a consequence of the competition of forces acting on the interface at different lengthscales, has been characterized in low-viscosity, forced-flow imbibition displacements obtaining a super-rough scaling scenario. The complex spatio-temporal dynamics of the front is studied at the statistically-stationary state of saturated front roughness in forced-flow experiments. We have analysed the spatial and temporal correlations of velocities of the front from the local scale, much smaller than the lateral correlation length and the characteristic length of the disorder, to the system size. Imbibition fronts exhibit burst-like dynamics, advancing by spatially-localized avalanches. These avalanches are power-law distributed in sizes and durations with exponential cutoffs. Power-law exponents are independent of the experimental conditions while the cutoffs diverge as Ca is reduced. We study also the intermittent character of these displacements by analysing different moments of the statistical distributions of velocity increments as a function of the time lag. We show that intermittency is controlled by two parameters only. The ensemble of results presented in this Thesis supports a very general picture of the nonequilibrium dynamics of slowly-driven fronts in open fractures. The lateral propagation of interfacial fluctuations is controlled by local mass conservation, through the lateral correlation length. The advancement of the interface in the direction of propagation is controlled by the characteristic extent of the disorder and by the mean front velocity.
L'objectiu de la tesi és l'estudi de la dinàmica espacio-temporal de la interfície entre aire desplaçat i oli invasor, en desplaçaments d'imbibició a través d'un model de fractura oberta. La recerca presentada combina un extens i exhaustiu treball experimental amb una anàlisi de dades acurada, basada en mètodes utilitzats en física estadística de no-equilibri. El procés d'imbibició, en que el fluid invasor mulla preferentment el medi envaït, és rellevant en diverses situacions d'interès, des de fluxos fisiològics a la irrigació del sòl i l'extracció de petroli. També és un sistema model interessant per a l'estudi de problemes de física fonamental degut a les correlacions de llarg abast que es desenvolupen al front, que indueixen una dinàmica complexa. Primer s'estudia l'avançament de la posició mitjana del front de fluid en condicions d'imbibició espontània (ascens capil•lar). Hem proposat una nova solució analítica que reprodueix els resultats experimentals tant amb presència de gravetat efectiva oposant-se a l'avançament del fluid com sense. En experiments d'imbibició forçada s'ha caracteritzat el procés d'arrugament dinàmic (kineticroughening) del front oli-aire a baixa viscositat. L'escenari d'escalament observat és super-rugós. Finalment s'ha estudiat la dinàmica del sistema en el règim estadísticament estacionari. S'han analitzat les correlacions temporals i espacials de les velocitats des de l'escala local, per sota la mida de les heterogeneïtats del desordre, fins a la mida del sistema. El front mostra una dinàmica a batzegades caracteritzada en termes d'allaus. Les mides i durades d'aquestes allaus estan distribuïdes estadísticament en llei de potències, amb exponents independents de les condicions experimentals, amb un truncament exponencial, que divergeix en reduir el nombre de capil•laritat. La intermitència del senyal s'ha quantificat i se n'ha extret els dos paràmetres que la controlen. El conjunt de resultats presentats en aquesta tesi dóna suport a una descripció molt general de la dinàmica de propagació lenta de fronts d'imbibició fora de l'equilibri en fractura oberta. La conservació local de massa controla la correlació lateral de les fluctuacions de la interfície. La longitud característica de les illes de desordre i la velocitat mitjana del front, per la seva banda, controlen l'avançament del front en la direcció de propagació.

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Clotet-Fons, Xavier. "Imbibition in a model open fracture - Capillary rise, kinetic roughening and intermittent avalanche dynamics." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2014. http://tel.archives-ouvertes.fr/tel-01068638.

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The heterogeneous structure of fractured media can lead to complex spatiotemporal fluid invasion dynamics. It thus brings forward challenging fundamental questions in the context of out-of-equilibrium dynamical systems, but also relevant to many processes of interest. The goal of the Thesis is to study the spatio-temporal dynamics of the oil-air interface between displaced air and invading oil, in imbibition through a model open fracture. The research combines exhaustive experimental work with accurate data analysis based on methods of nonlinear statistical physics. The mean postion of the interface h(t) is studied in capillary rise experiments, giving rise to a new analytical solution for h(t). The fluctuations of the interface in forced-flow experiments are analysed in the context of kinetic roughening, characterizing a super-rough scaling scenario. Finally, the burst-like dynamics is studied by analysing the local and global velocities of the front, which are widely distributed and display complex spatio-temporal correlations. We define local and global avalanches whose sizes and durations are also widely distributed, with cutoffs that diverge with the capillary number. Intermittentcy of the global signal is quantified. The ensemble of results presented in this Thesis supports a very general picture of the nonequilibrium dynamics of slowly-driven fronts in open fractures: the lateral propagation of interfacial fluctuations is controlled by local mass conservation, through the lateral correlation length; and the advancement of the interface in the direction of propagation is controlled by the characteristic extent of the disorder d and by the mean front velocity.

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Raymond, Miriam Shirley. "Practical assessment of fractured rock hydrogeology in the open cut area at Northparkes Mines, NSW." Thesis, University of Canterbury. Geological Science, 2002. http://hdl.handle.net/10092/6426.

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As the open pit mines at Northparkes near the end of their productive life, a better understanding of site hydrogeology is needed in order to set achievable aims for mine rehabilitation. This has been accomplished in this thesis by defining an improved conceptual hydrogeologic model for the open cut area, using an environmental framework to expound the interconnections between water in each component of the physical environment. Groundwater around the open pits is contained within secondary porosity features of trachyandesitic and intrusive lithologies. The water table is approximately 40 m below the land surface, overlain by regolith of variable thickness that has formed from a long history of chemical weathering. The hydrogeology is strongly influenced by the semi-arid environmental conditions, with long recharge and discharge pathways. Forming a conceptual understanding of the system has required rational analysis of sporadic data from short monitoring programs, which are prone to a high degree of error because of the heterogeneous and isotropic nature of the groundwater medium. Low mine inflows and subtle piezometric gradients are evidence for very slow groundwater movement in the area. There is a steep piezometric gradient surrounding each open-pit mine and less than 50 m from each pit perimeter the water table remains at its pre-mining position. The hydrogeologic data is consistent with a model whereby the bulk of groundwater occurs within a layer of oxide rock (saprock), situated beneath the intensely weathered saprolite and above fresh sulphide rock. The saprock represents a layer of enhanced permeability within the profile; it follows the undulating weathering front, and it has variable depth and thickness. In the sulphide rocks, hydraulic conductivity is strongly dependent on the type of fracture infill and the existence of open fracturing. Drilling data indicates that open fracturing declines with depth and is not encountered below a depth of 300 m. Classical pumping test data for the area is limited; estimates of hydraulic conductivity are <0.5 m/day in fractured sulphide rock. The results of slug test testing are consistent with this, indicating that hydraulic conductivity is variable but generally very low. Two new piezometers in the open cut area with short screened sections revealed that hydraulic conductivity in the oxide zone is at least an order of magnitude higher than in the sulphide zone. This research has shown that the position of the water table is controlled by rock fracture characteristics, the thickness of the weathered profile, and proximity to areas of shallow bedrock that receive direct rainfall recharge. Recharge in most areas is hindered by thick swelling clay soils and regolith units. Data from monitoring bores across the Upper Bogan valley showed that the water table responds very slowly to rainfall trends and land use changes. Groundwater quality in the area is moderate to poor, small pockets of low salinity water are confined to shallow depths near recharge outcrops. Groundwater composition is strongly influenced by the reactivity of fracture infill, mineralisation history, and the intensity of weathering processes. There is no evidence that mining at Northparkes has markedly altered groundwater chemistry. Analysis of groundwater samples from monitoring bores and pit wall seepage showed there are three general hydrochemical facies across the mine site. These represent consecutive stages in the evolution of groundwater chemistry with distance from recharge and with residence time in the rocks, according to a classic Chebotarev sequence. Groundwater with relatively low salinity (<3000 mg/l TDS) and a calcium-bicarbonate signature occurs close to bedrock outcrops, where direct rainfall recharge is thought to primarily occur. A short distance from recharge outcrops, TDS increases to 3000-10000 mg/l and groundwater composition is calcium sulphate or calcium chloride type due to wall-rock reactions and reducing conditions in the formation. Groundwater with a sodium-chloride signature and high TDS (> 10000 mg/l), is found deep in the profile and in areas overlain by thick, confining regolith material. Rapid evolution to sodium-chloride type groundwater is ensured by the nature of fracture infill in the crystalline lithologies, and high cation exchange capacity of the extensively weathered material. The hydrochemical data is consistent with geological evidence that groundwater in the Northparkes area is compartmentalised by lithologic, structural and weathering features in the profile. Exploration drilling has shown there are small basins of deeply weathered material isolated by faults and areas of low permeability, unaltered rock. Groundwater within each compartment is essentially stagnant and saline, and as a result it has very low resource potential. This research has provided a conceptual framework for the hydrogeologic system, which will facilitate further work to help to ensure environmental sustainability of open cut rehabilitation plans. Future work should be directed towards quantifying components of the system that are still poorly understood, such as recharge and vadose zone processes.

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Zeno, Mohamed Saaed [Verfasser]. "Long-term results after open reduction of the subcondylar fracture via - modified Risdon approach / Mohamed Saaed Zeno." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2015. http://d-nb.info/1079525084/34.

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Wullschleger, Martin Eduard. "Effect of surgical approach on bone vascularisation, fracture and soft tissue healing : comparison of less invasive to open approach." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/38523/1/Martin_Wullschleger_Thesis.pdf.

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Over the past ten years, minimally invasive plate osteosynthesis (MIPO) for the fixation of long bone fractures has become a clinically accepted method with good outcomes, when compared to the conventional open surgical approach (open reduction internal fixation, ORIF). However, while MIPO offers some advantages over ORIF, it also has some significant drawbacks, such as a more demanding surgical technique and increased radiation exposure. No clinical or experimental study to date has shown a difference between the healing outcomes in fractures treated with the two surgical approaches. Therefore, a novel, standardised severe trauma model in sheep has been developed and validated in this project to examine the effect of the two surgical approaches on soft tissue and fracture healing. Twenty four sheep were subjected to severe soft tissue damage and a complex distal femur fracture. The fractures were initially stabilised with an external fixator. After five days of soft tissue recovery, internal fixation with a plate was applied, randomised to either MIPO or ORIF. Within the first fourteen days, the soft tissue damage was monitored locally with a compartment pressure sensor and systemically by blood tests. The fracture progress was assessed fortnightly by x-rays. The sheep were sacrificed in two groups after four and eight weeks, and CT scans and mechanical testing performed. Soft tissue monitoring showed significantly higher postoperative Creatine Kinase and Lactate Dehydrogenase values in the ORIF group compared to MIPO. After four weeks, the torsional stiffness was significantly higher in the MIPO group (p=0.018) compared to the ORIF group. The torsional strength also showed increased values for the MIPO technique (p=0.11). The measured total mineralised callus volumes were slightly higher in the ORIF group. However, a newly developed morphological callus bridging score showed significantly higher values for the MIPO technique (p=0.007), with a high correlation to the mechanical properties (R2=0.79). After eight weeks, the same trends continued, but without statistical significance. In summary, this clinically relevant study, using the newly developed severe trauma model in sheep, clearly demonstrates that the minimally invasive technique minimises additional soft tissue damage and improves fracture healing in the early stage compared to the open surgical approach method.

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Lin, Y. "Optimum design for sustainable 'green' overlays : controlling flexural failure." Thesis, Coventry University, 2014. http://curve.coventry.ac.uk/open/items/b5ba73e5-9cb8-4a0b-ac99-c53b3c3e54ed/1.

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The target of the ‘Green Overlays’ research was a cost effective, minimal disruption, sustainable and environmentally friendly alternative to the wholesale demolition, removal and complete reconstruction of the existing structural concrete pavement. The important problem of flexural resistance for strengthening concrete pavements with structural overlays has been scrutinised. A new mix design method for steel fibre reinforced, roller compacted, polymer modified, bonded concrete overlay has been proposed. The mixes developed were characterized of high flexural strength and high bond strength with the old concrete substrate. ‘Placeability’ and ‘compactability’ of the mix were two dominant issues during laboratory investigation. An innovative approach for establishing the relationship between Stress and Crack Face Opening Displacement for steel fibre reinforced concrete beams under flexure was developed. In addition, a new and simple method for calculating the interfacial Strain Energy Release Rate of both, a two-dimensional specimen and a three-dimensional model of the overlay pavement system were developed. This method can be readily and easily used by practicing engineers. Finally, a new test specimen and its loading configuration for measuring interfacial fracture toughness for concrete overlay pavements were established. The interfacial fracture toughness of a composite concrete beam, consisted of steel fibre-reinforced roller compacted polymer modified concrete bonded on conventional concrete and undergoing flexure, was assessed. In summary, this thesis presents four key findings: A new mix design method for steel fibre-reinforced roller compacted polymer modified concrete bonded on conventional concrete. A new method for establishing the fibre bridging law by an inverse analysis approach. A new, simplified method for calculating strain energy release rate at the interface of a composite beam. A new, innovative technique for calculating strain energy release rate at the interface of an overlaid pavement. The thesis contains a plethora of graphs, data-tables, examples and formulae, suitable for future researchers.

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Fischer, Miriam. "Evolution of the fossil hydrothermal system at Long Valley Exploratory Well, Mammoth Lakes, California, USA the record of open fracture mineralization at 2600 m depth and numerical simulations /." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970060289.

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Seon, Guillaume. "Finite element-based failure models for carbon/epoxy tape composites." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28117.

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20

Oliveira, Priscila Rosalba Domingos de. "Incidência e fatores associados à ocorrência de infecção de sítio cirúrgico nas fraturas diafisárias do fêmur e da tíbia tratadas com haste intramedular: estudo prospectivo." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/5/5140/tde-23102018-092906/.

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INTRODUÇÃO: As fraturas diafisárias do fêmur e da tíbia encontram-se em destaque devido a sua elevada incidência e alto impacto econômico e social. A osteossíntese com uso da haste intramedular (HIM) é o procedimento cirúrgico de escolha. A infecção de sítio cirúrgico (ISC) relacionada a HIM é considerada uma complicação grave e de difícil tratamento. OBJETIVOS: 1. Determinar a incidência de ISC após a implantação de HIM para fixação de fraturas diafisárias de fêmur e tíbia. 2. Avaliar os possíveis fatores associados. MÉTODOS: Estudo prospectivo observacional do tipo coorte. Para definição de ISC, foram utilizados os critérios do CDC-NHSN. A incidência de ISC foi calculada como a relação entre o número de pacientes com ISC em relação ao número total de pacientes. Para avaliação dos potenciais fatores associados, foram analisados aqueles relacionados aos pacientes (idade, gênero, índice de massa corpórea, presença de focos ativos de infecção à distância, presença condições imunossupressoras, avaliação de estado físico segundo escore ASA, etilismo, tabagismo, uso de drogas ilícitas, politrauma, etiologia do trauma, tipo de fratura quanto à exposição óssea, classificação da fratura segundo Müller AO, classificação segundo Tcherne para as fraturas fechadas, classificação segundo Gustilo-Anderson para as fraturas expostas, permanência em outro serviço de saúde, uso prévio de fixador externo, antecedente de manipulação cirúrgica na topografia da fratura, uso de hemoderivados); dos fatores relacionados ao ambiente cirúrgico e ao ato operatório (classificação da ferida quanto ao potencial de contaminação, duração da cirurgia, tricotomia, possível contaminação intraoperatória, uso de antimicrobianos relacionados ao procedimento cirúrgico, uso de drenos, ocorrência de hipotermia ou hipóxia no período perioperatório, tipo de HIM utilizada, fresagem, necessidade de necessidade de reparo do revestimento cutâneo associado à topografia da fratura, uso de terapia por pressão negativa) e dos fatores relacionados à microbiota (colonização por S. aureus ou A. baumannii). RESULTADOS: 221 pacientes foram incluídos e completaram o período de 12 meses de seguimento. A incidência de ISC associada à osteossíntese com HIM foi de 11,8%. Na análise inicial por regressão logística não ajustada, os seguintes fatores apresentaram associação com ISC: etiologia do trauma relacionada a acidentes de carro e bicicleta, classificação Müller AO do traço da fratura 2 ou 3, uso prévio de fixador externo, cirurgias com maiores tempos de duração, uso de drenos, uso de terapia por pressão negativa e necessidade de reparo do revestimento cutâneo na topografia da fratura. Na análise ajustada por regressão logística múltipla, contudo, apenas o uso prévio de fixador externo e a necessidade de reparo do revestimento cutâneo mantiveram-se associados à ocorrência de ISC. CONCLUSÕES: A incidência de ISC associada à fixação de fraturas diafisárias de fêmur e tíbia com HIM foi de 11,8%. O uso prévio de fixadores externos e a necessidade de reparo do revestimento cutâneo na topografia da fratura foram fatores associados à ocorrência de infecção
BACKGROUND: Diaphyseal fractures of femur and tibia are prominent due to its high incidence and high economic and social impact. Intramedullary nailing (IN) is the surgical procedure of choice. Surgical site infection (SSI) related to this procedure is considered a difficult to treat complication. OBJECTIVES: Determine the incidence of SSI after IM in femoral and tibial diaphyseal fractures and evaluate possible risk factors. METHODS: Prospective observational cohort study. SSI was defined according to CDC-NHSN criteria. Incidence of SSI was calculated as the ratio between the number of patients with SSI and total number of patients. Analysis of potential risk factors included patients-related factors (age, gender, body mass index, active foci of infection, immunosuppressive conditions, ASA score, alcohol or illicit drug abuse, smoking, polytrauma, etiology of fracture, type of fracture if closed or open, classification of fracture according to Müller AO, Tcherne classification for closed fractures, to Gustilo-Anderson classification for open fractures, previous surgical manipulation, use of blood products); environmental and surgical-related factors (surgical wound classification, duration of surgery, hair removal, intraoperative contamination, antimicrobial use, presence of drains, hypothermia or hypoxia in the perioperative period, type of IN used, reaming, need for muscle or skin flap repair, use of negative pressure therapy) and microbiotarelated factors (S. aureus and A. baumannii colonization). RESULTS: 221 patients were included and completed the 12-month follow-up period. Incidence of SSI was 11.8%. In the initial analysis by unadjusted logistic regression, following factors were associated SSI: trauma etiology related to car and bicycle accidents, Müller AO classification of the fracture morphology groups 2 or 3, previous use of external fixator, surgeries with larger length of time, presence of drains, use of negative pressure therapy and need for muscle or skin flap repair. In the multiple logistic regression-adjusted analysis, previous use of external fixator and need for muscle or skin flap repair remained associated with SSI. CONCLUSIONS: Incidence of SSI associated with IN for femoral and tibial diaphyseal fractures was 11.8%. Previous use of external fixators and need for muscle or skin flap repair were factors associated with occurrence of infection

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Treasurer, Paul James. "Characterization and Analysis of Damage Progression in Non-Traditional Composite Laminates With Circular Holes." Thesis, Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/13989.

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Carbon Fiber / Epoxy Laminates are increasingly being used in the primary structure of aircraft. To make effective use these materials, it is necessary to consider the ability of a laminate to resist damage, as well as material strength and stiffness. A possible means for improving damage tolerance is the use of non-traditional composite laminates, in which the longitudinal 0 plies are replaced with 5 or 10 plies. The main objectives of this collaborative Georgia Tech / Boeing research was the characterization of these non-traditional laminates, and the determination of appropriate lamina-level analytical techniques that are capable of predicting the changes caused by the use of slightly off-axis longitudinal plies. A quasi-isotropic [45/90/-45/theta/45/90/-45/-theta]s and hard [45/theta/-45/theta/90/45]s lay-up, where theta =0,5 or 10, were tested in open hole tension, filled hole tension, open hole compression, single shear bearing, and unnotched tension. These coupon level tests illustrated the effects of lay-up, notch constraint, and load type on traditional and non-traditional laminates. Die penetrant enhanced in-situ radiography was performed to determine the extent of damage suppression. The use of non-traditional laminates was found to reduce longitudinal ply cracking and delamination, with significant effect on the stress distribution around the notch. The use of non-traditional laminates also resulted in a 15%-20% improvement in bearing strength of the traditional laminates. Several predictive techniques were implemented to evaluate their ability to predict the effect of slight changes in ply orientations. A progressive damage model was written to compare Tsai-Wu, Hashin, and Maximum Stress unnotched strength criterion. Additionally, several semi-empirical failure theories for notched strength prediction were compared with linear and bi-linear cohesive zone models to determine applicability to non-traditional laminates.

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Fontes, Raphael Siqueira. "Comp?sito Polim?rico H?brido: Comportamento Mec?nico, Descotinuidade Geom?trica e Resist?ncia Residual." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15693.

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The growing demand in the use of hybrid composite materials makes it essential a better understanding of their behavior face of various design conditions, such as the presence of geometric discontinuities in the cross section of structural elements. This way, the purpose of this dissertation is a study of the mechanical response (strength and stiffness), modes (characteristics) of fracture and Residual Strength of an hybrid polymeric composite with and without a geometric discontinuity in its longitudinal section (with a reduction in the cross section) loaded by uniaxial tension. This geometric discontinuity is characterized by central holes of different diameters. The hybrid composite was fabricated as laminate (plate) and consisting of ortho-tereftalic polyester matrix reinforced by 04 outer layers of Jute fibers bidirectional fabrics and 01 central layer of E-glass bidirectional fabric. The laminate was industrially manufactured (Tecniplas Nordeste Ind?stria e Com?rcio Ltda.), obtained by the hand lay-up technique. Initially, a study of the volumetric density of the laminate was made in order to verify its use in lightweight structures. Also were performed comparative studies on the mechanical properties and fracture modes under the conditions of the specimens without the central hole and with the different holes. For evaluating the possible influence of the holes in the structural stability of the laminate, the Residual Strength of the composite was determined for each case of variation in hole diameter. As a complementary study, analyses of the macroscopic final fracture characteristic of the laminates were developed. The presence of the central hole of any sizes, negatively changed the ultimate tensile strength. Regarding the elastic modulus, moreover, the difference found between the specimens was within the range of tests displacement, showing the laminate stability related to the stiffness
A crescente demanda na utiliza??o dos materiais comp?sitos h?bridos torna imprescind?vel uma melhor compreens?o do seu comportamento frente ?s mais diversas condi??es de projeto, como a presen?a de descontinuidades geom?tricas nos elementos estruturais. Nesse sentido, a proposta desta disserta??o ? um estudo envolvendo a resposta mec?nica (resist?ncia e rigidez), os modos (caracter?sticas) da fratura e Resist?ncia Residual de um laminado comp?sito h?brido de matriz polim?rica com e sem presen?a de descontinuidade geom?trica em sua se??o longitudinal (com redu??o da se??o transversal), sob a a??o de tra??o uniaxial. Essa descontinuidade geom?trica ? caracterizada por furos centrais de diferentes di?metros. O laminado comp?sito h?brido foi confeccionado na forma de placa e composto por matriz poli?ster orto-tereft?lica refor?ada por 04 camadas externas de tecidos bidirecionais de fibras de juta e 01 camada central de tecidos bidirecionais de fibras de vidro-E. O laminado foi fabricado industrialmente (Tecniplas Nordeste Ind?stria e Com?rcio Ltda.), obtido atrav?s do processo de lamina??o manual (hand lay-up). Inicialmente, foi feito um estudo da densidade volum?trica do laminado, de modo a comprovar sua aplica??o em estruturas leves. Foram realizados estudos comparativos entre as propriedades mec?nicas nas condi??es dos corpos de prova sem o furo e com os diferentes di?metros do furo. Para a avalia??o de poss?vel influ?ncia da presen?a dos furos centrais na estabilidade estrutural do laminado, a Resist?ncia Residual foi determinada para cada caso de varia??o do di?metro do furo. Como estudo complementar, an?lises macrosc?picas da caracter?stica de fratura final dos laminados foram desenvolvidas. A presen?a do furo central, independente do di?metro, influiu de forma danosa, principalmente na resist?ncia ?ltima ? tra??o. Quanto ao m?dulo de elasticidade, por outro lado, a diferen?a encontrada entre os corpos de prova apresentou-se dentro da faixa da dispers?o dos ensaios, mostrando estabilidade com rela??o ? rigidez do laminado

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Nguyen, Anh Tuan. "Influence des incertitudes géométriques et de la méthode de modélisation dans l'analyse de stabilité des talus rocheux : application aux mines à ciel ouvert." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0296/document.

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La stabilité des exploitations à ciel ouvert (mines ou carrières) excavées dans des massifs rocheux dépend de leur géométrie, des caractéristiques géométriques de la fracturation (orientation et espacement) du massif et des caractéristiques mécaniques du massif et des discontinuités. L'évaluation du risque d'instabilité rocheuse dépend de la quantité et la qualité des informations disponibles sur le massif rocheux et des méthodes d'analyse mises en œuvre pour évaluer le comportement mécanique de l'assemblage de blocs rocheux. Différents sites de talus naturels, d'excavation routière et de carrières et mines à ciel ouvert présentés dans le mémoire montrent que les informations connues peuvent beaucoup varier d'un site à l'autre. Les étapes de collecte et de synthèse des données, puis de modélisation afin d'analyser la stabilité d'une pente rocheuse conduisent à des incertitudes. Le mémoire traite plus particulièrement de l'influence des incertitudes géométriques et différentes méthodes de regroupement des fractures en familles sont explorées. La combinaison du travail proposé par différents auteurs conduit à une nouvelle méthode nommée PSMY. Cette méthode ainsi que la méthode spectrale ont été programmées sous l'environnement Mathematica et les résultats sont comparés à des regroupements "manuels" réalisé avec le logiciel DIPS. Les méthodes de regroupement sont présentées selon le pourcentage d'orientations classé par la méthode. L’orientation et l’espacement des familles de fractures sont ajustées à des lois statistiques. Les paramètres statistiques sont comparés en fonction de la méthode regroupement. Ces paramètres influencent la construction d'un modèle géométrique du massif rocheux appelé DFN (Discrete Fracture Network). L'influence des regroupements sur l'analyse de stabilité est étudiée à partir de modélisation stochastiques à l'équilibre limite utilisant les logiciels SWEDGE et RESOBLOK. Ces logiciels ne prennent pas en compte les mêmes incertitudes et en sortie ils fournissent des indicateurs de stabilité différents. Une analyse de sensibilité des indicateurs (nombre de blocs instables, volume moyen du bloc instable, volume total instable) aux méthodes de regroupement et aux orientations de talus est réalisée. Une analyse de variance permet de préciser l'influence de ces deux facteurs. Une évaluation de l’état de stabilité global du massif, en fonction de la cohésion et de l'angle de frottement est proposée. L'influence de la méthode de modélisation est évoquée en comparant des calculs tridimensionnels à l'équilibre limite et des modélisations bidimensionnel et tridimensionnels en éléments discrets rigides ou déformables. Un couplage entre le logiciel RESOBLOK (équilibre limite) et LMGC90 (éléments discrets) permet de comparer les analyses pour une même géométrie. Pour le cas de la déviation d'Ax-les-Thermes et certaines configurations géométriques instables l’influence des paramètres de modèles sur stabilité du talus est testée. Plusieurs variantes sont comparées. La simulation d’une excavation en 3D multi phases est réalisée et l’indice de mobilisation est étudié pour comparer les divers types de contacts dans LMGC90 par rapport à l’éventuel glissement des blocs dans les étapes successives
The stability of open-cast operations (mines or quarries), excavated in rock mass depends on their geometry, the geometrical characteristics of the rock mass fractures (orientation and spacing) and the mechanical characteristics of the rock mass and the discontinuities. The assessment of the rock instability risk depends on the quantity and quality of the available information on the rock mass and the analysis methods used for the evaluation of the mechanical behavior of the rock block collection. Different sites of natural rock slopes, of road cuts, and of open-cast mines and quarries, described in the present document, show that the known information can vary a lot from one site to the other. The steps of data gathering and analysis, then the modelling step used to analyze the stability of the rock slope, lead to uncertainties. The present work deals in particular with the influence of the geometrical uncertainties, and the different clustering methods, to define families of fractures, are examined. The combination of works suggested by several authors leads to a new method called PSMY. This method, together with the spectral method, was coded in the Mathematica platform, and the obtained results are compared with "hand-made" clusters, done with the DIPS software. The clustering methods are presented according to the ratio of classified orientations. The orientation and spacing of fracture families are fitted by statistical law. The statistical parameters are compared according to the clustering method used. These parameters have an influence on the construction of the rock mass geometrical model, called DFN (Discrete Fracture Network). The influence of the clusters on the stability analysis is studied from the stochastic models based on the limit equilibrium analysis, in the SWEDGE and RESOBLOK software. These programs do not take into account the same uncertainties, and as a result, they give different stability indicators. A sensitivity analysis of these indicators (number of unstable blocks, average volume of unstable blocks, and total volume of unstable blocks) versus the clustering methods used, and the orientation of the slopes, is carried out. A variance analysis allows an evaluation of the influence of these factors. The assessment of the global stability condition of the rock mass, depending on the cohesion and the friction angle, is proposed. The influence of the modeling method is analyzed by comparing 3D calculations using the limit equilibrium calculations, and 2D and 3D models using discrete rigid and deformable blocks. A coupling between RESOBLOK (limit equilibrium) and LMGC90 (discrete elements) allows the comparison of results on the same original geometry. For the case of Ax-les-Thermes road-cut, and for various unstable geometries, the influence of the model parameters is tested. Several cases are compared. The 3D simulation of an excavation, at different steps, is performed, and the mobilization index is studied, in order to compare several types of contacts, within the LMGC model, in relation to the possible sliding of blocks, at those different steps

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24

Pinheiro, João Francisco Durão da Costa Rosa. "Indication and Benefit of Early Debridement in Open Fractures of Lower Extremity Bones - A Systematic Review." Master's thesis, 2021. https://hdl.handle.net/10216/136123.

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25

Pinheiro, João Francisco Durão da Costa Rosa. "Indication and Benefit of Early Debridement in Open Fractures of Lower Extremity Bones - A Systematic Review." Master's thesis, 2021. https://hdl.handle.net/10216/139161.

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26

Носівець, Д. С. "Порівняльні характеристики способів лікування переломів дистального метаепіфізу плечової кістки : автореф. дис. на здобуття наук. ступеня канд. мед. наук / Д. С. Носівець. - Донецьк, 2012. - 22 с." Thesis, 2012. http://repo.dma.dp.ua/197/1/aref_%D0%9D%D0%BE%D1%81%D0%B8%D0%B2%D0%B5%D1%86_%D1%83%D0%BA%D1%80.pdf.

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Дисертація присвячена актуальній проблемі лікування хворих з переломами дистального метаепіфізу плечової кістки. В умовах експерименту досліджені особливості напружено-деформованого стану дистального метаепіфізу плечової кістки та установлено, що при навантаженні кисті 50,0 Н, величина напруги в зоні кісткових елементів складає 1,3 кН, що в 26 разів більше прикладеного зусилля. Фіксація спицями-гвинтами, пластинами і комбінованими конструкціями створює напругу від 18,7 до 95,2 кПа, а при фіксації апаратом Г.А. Ілізарова виникає напруга від 2,3 до 114,0 кПа, що може призводити до зміщення. Запропоновано спосіб комбінованого остеосинтезу при переломах дистального метаепіфізу плечової кістки. Визначені показання до способів лікування в залежності від типу перелому та доведена залежність розвитку ускладнень лікування від тривалості іммобілізації ліктьового суглоба. Розроблені періоди та підходи відновного лікування, встановлена залежність результатів відновного лікування від типу перелому та способу лікування. За результатами лікування 194 хворих з переломами дистального метаепіфізу плечової кістки встановлено, що при застосуванні диференційованих підходів лікування позитивні результати отримані у 91,4% хворих проти 71,2% в контрольній групі, та на 20,2% знижено кількість ускладнень.

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27

Ameli, Aboutaleb. "Hygrothemal Degradation of Toughened Adhesive Joints: The Characterization and Prediction of Fracture Properties." Thesis, 2011. http://hdl.handle.net/1807/29659.

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The main objective of this work was to develop a framework to predict the fracture toughness degradation of highly toughened adhesive joints using fracture test data obtained by accelerated open-faced degradation method. First, the mixed-mode fracture resistance (R-curve) behavior of two rubber-toughened epoxy-aluminum adhesive systems was measured and could be fit in a bilinear R-curve model. Then, open-faced DCB (ODCB) specimens of the same adhesive systems were aged over a relatively wide range of temperature, relative humidity (RH) and time, dried and tested to characterize the irreversible evolution of the mixed-mode fracture R-curves. The R-curve bilinear model parameters of adhesive system 1 varied significantly with degradation while that of adhesive system 2 remained unchanged. The absorption and desorption of water in the adhesives cast wafers was measured gravimetrically. The absorption data were fitted to a new sequential dual Fickian (SDF) model while water desorption was modeled accurately using Fick’s law. A significant difference was observed between the amounts of retained water in the two adhesives after drying. An exposure index (EI) was defined as the integral of water concentration over time and calculated at all points in the ODCB and closed DCB joints. The fracture toughness of the closed joints was then predicted from these calculated EIs by making reference to fracture toughness data from the ODCB specimens degraded to various EI levels. To verify the predictions, fracture experiments and analyses were carried out for closed DCB joints. Good agreement was found between the predicted and experimentally measured fracture toughness values for the degraded closed DCB joints. Furthermore, the crack path and fracture surface characteristics were evaluated as a function of the degree of aging using optical profilometery. The unexpected crack path in the mixed-mode fracture of unaged open-faced DCB specimens was addressed. The results showed a strong relationship between fracture surface parameters and the critical strain energy release rate, Gcs, irrespective of the type of adhesive and exposure condition.

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LIN, MENG-YI, and 林孟宜. "A Study of Patient Experience about Open Reduction and Internal Fixation surgery Of Fracture and Dislocation." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/82983928297312555812.

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碩士
國立雲林科技大學
工業工程與管理系
104
In recent years, It is often to here that healthcare institutions prepared fake file for Hospital accreditation. To encourage healthcare institutions implement the daily manage and reduce pressure of hospital colleagues, Ministry of Health and Welfare is reforming the mode of Hospital accreditation, such as: Streamlining provisions, Patient Focus Methodology(PFM) instead of Investigating paperwork. PFM case is chosen by the high-volume or high-risk disease of the healthcare institutions, and visited with the patient care process each patient care team, checked medical records, access to care personnel or even visit the patient in order to understand healthcare institutions meet the criteria. Therefore, it is an important issue to implement disease management for hospital supervision and management team. In addition, Taiwan hospital accreditation also refer CAHPS of the United States, require hospital must have patient experience investigation in 2014. Therefore, this study combined patient experience and disease management to explore the patient experience about “Open Reduction and Internal Fixation surgery Of Fracture and Dislocation”. The results of this study are: patient experienced average is 4.36, most of the patient living in Yunlin County and Chiayi County. Independent samples T test showed that patient experience average scores are lower when the patient self-assessment of the severity of the disease is a serious and critical condition, or when the self-assessment during the hospitalization is too short, or the ward room belongs to double or single rooms. In the correlation analysis we found that the patient experience of emergency medical treatment overall experience score correlation is not significant. The nurses in the hospital performance, overall performance of patient experience scores were highly correlated. . Keywords：Patient experience, Open Reduction and Internal Fixation surgery Of Fracture and Dislocation

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29

Huang, Sheng-Hsiung, and 黃勝雄. "The Impact of Case Payment System on Health Resources Utilization- A Case Study of Open Reduction of Close Fracture in a Regional Hospital." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/76983072264227495513.

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碩士
中國醫藥學院
醫務管理研究所
88
The case payment system of orthopedic close fracture has been implemented in July 1999. The Bureau of National Healthcare Insurance (NHI) introduces All Patients Diagnosis Related Groups (AP-DRGs) and creates the classification of diseases based on the case payment system. So far for service belonging to case payment, they are practiced by hospitals according to different level and codes respectively. Except in medical center, case payment service of orthopedic close fracture merely reimbursed in regional hospital. This research was based on patients who received open reduction of close fracture is femoral shaft, neck and radius or ulna at a regional hospital from October 1, 1998 to March 31, 2000. Relative issues are studied and analyzed by gathering the medical expenditure bills and descriptions of orders that the regional hospital applied to the Bureau of NHI for reimbursement. The objectives of this study are to inquire the impacts with the implementation of case payment service brought to the health resources utilization. The results provide some important application to the concerns about the establishment of case payment method for policy-maker, and about the adaptation of strategic response to case payment method for hospital administrators. The length of stay (LOS) of open reduction of close fracture with femoral shaft or neck increased 0.07 days and total medical fee (TMF) increased NT$177 after the implementation of case payment method, but there are not statistically significant difference. After controlling characteristics of complication and comorbidity, the LOS of open reduction for close fracture in femoral shaft or femoral neck (AP-DRG 211) are reduced 1.67 day and the TMF also decreased NT$ 15541 after the implementation of case payment method. But there are not statistically significant different between before and after implementation of the case payment method. Besides, the operation and injection fee was decreased significantly. On the other hand, the radiology fee increased markedly . The LOS of open reduction for close fracture in radius or ulna was statistically significantly reduced 1.18 days and its TMF also decreased NT$ 5786(P<0.05). Control characteristics of complication or comorbidity, the LOS of AP-DRG 224 was reduced 0.62 day (P>0.05) and TMF was decreased NT$ 2615(P<0.05) after the implementation of case payment method. Besides, operation fee, medications fee, and injection fee were decreased significantly. On the other hand, the orders inspection fee and radiology fee were increased markedly in AP-DRG 224 without complication or comorbidity . Briefly, there are some suggestions to the Bureau of NHI that AP-DRG also considered the effective factors of the health care resource utilization are included age, complication / comorbidity of patient. But the reimbursement system strongly, deeply effects the health care resource utilization. Before enlarge the case payment system of AP-DRG, the practically case-mix should be clearly readjusted weighting value and reconstructed the payment standard systematically.

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30

"Healing of the patellar tendon donor site after the removal of the central one-third for anterior cruciate ligament reconstruction: a comparison between 'close' and 'open' procedure." Chinese University of Hong Kong, 1995. http://library.cuhk.edu.hk/record=b5888382.

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Li Chi Kei.
Thesis (M.Phil.)--Chinese University of Hong Kong,1995.
Includes bibliogrpahical references (leaves 54-68).
Abstract --- p.1
Acknowledgments --- p.4
Lists of Figures --- p.5
List of Tables --- p.8
Chapter Chapter 1 --- Introduction --- p.9
Chapter 1.1 --- Ligamental Injury --- p.9
Chapter 1.2 --- ACL Injury --- p.10
Chapter 1.3 --- Patellar Tendon and Anterior Cruciate Ligament --- p.11
Chapter 1.4 --- Patellar Tendon Bone Graft --- p.13
Chapter 1.41 --- Strength of the Patellar Tendon Bone Graft --- p.13
Chapter 1.42 --- Use of the Patellar Tendon Bone Graft --- p.14
Chapter 1.5 --- Patellar Tendon Bone Graft in Anterior Cruciate Ligament Reconstruction --- p.14
Chapter 1.6 --- Complications of Anterior Cruciate Ligament Reconstruction after the Use of Patellar Tendon Bone Graft --- p.16
Chapter 1.7 --- Healing of the Patellar Tendon Donor Site --- p.17
Chapter 1.8 --- Objective of the Study --- p.22
Chapter 1.9 --- Significance of the Study --- p.22
Chapter Chapter 2 --- Material & Method --- p.24
Chapter 2.1 --- Animal Model --- p.24
Chapter 2.2 --- Grouping --- p.24
Chapter 2.3 --- Operative Procedure --- p.24
Chapter 2.4 --- Method of Assessment --- p.26
Chapter 2.41 --- Gross Morphology --- p.26
Chapter 2.42 --- Biomechanical Testing --- p.27
Chapter 2.43 --- Biochemical Assay --- p.28
Chapter 2.43.1 --- Water Content --- p.29
Chapter 2.43.2 --- Collagen Content --- p.29
Chapter 2.44 --- Histology --- p.30
Chapter 2.45 --- Immunohistochemistry --- p.31
Chapter 2.5 --- Statistics --- p.32
Chapter Chapter 3 --- Results --- p.33
Chapter 3.1 --- Operation Complications --- p.33
Chapter 3.2 --- Gross Morphology --- p.33
Chapter 3.21 --- Dimension of the Patellar Tendon --- p.33
Chapter 3.22 --- Dimension of the Patellar Tendon Bone Graft --- p.33
Chapter 3.23 --- Dimension of the Remain Patellar Tendon --- p.34
Chapter 3.24 --- Gross Appearance of the Patellar Tendon Donor Site --- p.35
Chapter 3.3 --- Biomechanical Testing --- p.36
Chapter 3.31 --- Failure Load --- p.36
Chapter 3.32 --- Ultimate Stress --- p.37
Chapter 3.33 --- Stiffness --- p.37
Chapter 3.34 --- Energy Absorbed before Failure --- p.38
Chapter 3.4 --- Biochemical Assay --- p.38
Chapter 3.41 --- Water Content --- p.38
Chapter 3.42 --- Collagen Content --- p.39
Chapter 3 .5 --- Histology & Immunohistochemistry --- p.39
Chapter 3.51 --- Morphology of Control Tendon --- p.40
Chapter 3.52 --- Morphology of Experimental Tendon with 'Open' Procedure --- p.40
Chapter 3.53 --- Morphology of Experimental Tendon with 'Close' Procedure --- p.41
Chapter 3.54 --- Healing at the Patellar and Tibial Insertion Site --- p.41
Chapter 3.55 --- Morphology of the Cartilage Surface --- p.42
Chapter Chapter 4 --- Discussion & Conclusion --- p.43
Chapter 4.1 --- Gross Morphology --- p.43
Chapter 4.2 --- Biomechanical Testing --- p.45
Chapter 4.3 --- Biochemical Assay --- p.47
Chapter 4.4 --- Histology & Immunohistochemistry --- p.49
Chapter 4.5 --- Conclusion --- p.51
References --- p.54
Figures
Tables
Appendix

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Fischer, Miriam [Verfasser]. "Evolution of the fossil hydrothermal system at Long Valley Exploratory Well, Mammoth Lakes, California, USA : the record of open fracture mineralization at 2600 m depth and numerical simulations / von Miriam Fischer." 2003. http://d-nb.info/970060289/34.

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Dissertations / Theses on the topic 'Fractures, Open'

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