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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.
21

Studies on segmental displacement after Le Fort I and bilateral sagittal split osteotomies stabilized by rigid internal fixation

Wall, Gert. January 2001 (has links)
Thesis (doctoral)--Malmö University, Sweden, 2001. / Added t.p. with thesis statement inserted. Includes bibliographical references.
22

External fixation of tibial fractures presentation of a newly designed external fixator /

Haarman, Hendrikus Johannus Theodorus Maria, January 1980 (has links)
Thesis (doctoral)--Rijksuniversiteit te Utrecht.
23

In vitro evaluation of veterinary and human suture anchors in metaphyseal bone of the canine tibia

Robb, Julie Lynn. January 2006 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2006. / "August 2006" The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. Includes bibliographical references.
24

A new design of external fixator for long bone fracture management

Pohl, Anthony P. January 1999 (has links) (PDF)
Bibliography: leaves 216-231. Examines the sliding capability of external fixators under load and describes the development and testing of an external fixator capable of providing axial cyclic motion to a fracture site while a patient is walking.
25

Development and Validation of a Novel Biomechanical Testing Setup and Procedure for Olecranon Fracture Fixation Assessment

January 2015 (has links)
abstract: Olecranon fractures account for approximately 10% of upper extremity fractures and 95% of them require surgical fixation. Most of the clinical, retrospective and biomechanical studies have supported plate fixation over other surgical fixation techniques since plates have demonstrated low incidence of reoperation, high fixation stability and resumption of activities of daily living (ADL) earlier. Thus far, biomechanical studies have been helpful in evaluating and comparing different plate fixation constructs based on fracture stability. However, they have not provided information that can be used to design rehabilitation protocols such as information that relates load at the hand with tendon tension or load at the interface between the plate and the bone. The set-ups used in biomechanical studies have included simple mechanical testing machines that either measured construct stiffness by cyclic loading the specimens or construct strength by performing ramp load until failure. Some biomechanical studies attempted to simulate tendon tension but the in-vivo tension applied to the tendon remains unknown. In this study, a novel procedure to test the olecranon fracture fixation using modern olecranon plates was developed to improve the biomechanical understanding of failures and to help determine the weights that can be safely lifted and the range of motion (ROM) that should be performed during rehabilitation procedures. Design objectives were defined based on surgeon's feedback and analysis of unmet needs in the area of biomechanical testing. Four pilot cadaveric specimens were prepared to run on an upper extremity feedback controller and the set-up was validated based on the design objectives. Cadaveric specimen preparation included a series of steps such as dissection, suturing and potting that were standardized and improved iteratively after pilot testing. Additionally, a fracture and plating protocol was developed and fixture lengths were standardized based on anthropometric data. Results from the early pilot studies indicated shortcomings in the design, which was then iteratively refined for the subsequent studies. The final pilot study demonstrated that all of the design objectives were met. This system is planned for use in future studies that will assess olecranon fracture fixation and that will investigate the safety of rehabilitation protocols. / Dissertation/Thesis / Masters Thesis Bioengineering 2015
26

Avaliação do bloqueio paravertebral cervical com ropivacaína em cães anestesiados pelo isofluorano e submetidos à osteossíntese radio-ulnar

Cardoso, Guilherme Schiess [UNESP] 23 February 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-23Bitstream added on 2014-06-13T18:31:37Z : No. of bitstreams: 1 cardoso_gs_me_botfm.pdf: 985084 bytes, checksum: 646b38379c09aefed563ffcbee2f4812 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os animais são capazes de sentir dor e esta influencia a qualidade da recuperação anestésica e o resultado pós-cirúrgico. Os bloqueios anestésicos de nervos periféricos são cada vez mais utilizados para prevenir e aliviar a dor, sendo a abordagem paravertebral cervical do plexo braquial (raízes C6, C7, C8 e T1) uma alternativa para a anestesia do membro torácico de caninos. A ropivacaína é um anestésico local altamente lipossolúvel, de longa ação e que produz analgesia confiável com bloqueio motor mínimo. Objetivou-se com esse estudo avaliar o bloqueio paravertebral cervical do plexo braquial em cães com ropivacaína 1% comparando-se duas técnicas de localização das raízes nervosas: a palpação de referências anatômicas específicas e a utilização de estimulador de nervos periféricos. Foram empregados 24 cães submetidos à osteossíntese radio-ulnar sob anestesia geral inalatória com isofluorano, divididos aleatoriamente em quatro grupos distintos de acordo com os tratamentos: TI - SP: solução salina 0,9% perineural utilizando as referências anatômicas para localização das raízes nervosas cervicais; TII - SN: solução salina 0,9% utilizando as referências anatômicas e estimulador de nervos periféricos; TIII - RP: ropivacaína 1% perineural utilizando apenas referências anatômicas para localização das raízes nervosas cervicais; e TIV - RN: ropivacaína 1% utilizando as referências anatômicas e estimulador de nervos periféricos dessas raízes. Foram monitoradas as frequências cardíaca (FC) e respiratória (f), as pressões arteriais sistólica (PAS), média (PAM) e diastólica (PAD), a temperatura esofágica (Tº), a pressão parcial de dióxido de carbono (ETCO2) e a concentração de isofluorano (ETISO) ao final da expiração... / Animals are capable of feeling pain and this influences the quality of anesthesia recovery and outcome following surgery. The peripheral nerve blocks are increasingly used to prevent and relieve pain, and cervical paravertebral approach to the brachial plexus (roots C6 , C7, C8 and T1) is an alternative to anesthesia of the canine forelimb. The local anesthesics ropivacaine is highly soluble, long-acting and produces reliable analgesia with minimal motor block. The objectvice of this study was to evaluate the cervical paravertebral block of the brachial plexus with ropivacaine 1% and compare two techniques for localization of the nerve roots: palpation of anatomical landmarks and use of peripheral nerve stimulator. It was use 24 animals submitted to radio-ulnar osteosynthesis, randomly divided into four distinct groups according to treatment: TI - SP: perineural administration of 0,9% saline solution using anatomical landmarks to localization of the cervical nerve roots; TII - SN: perineural administration of 0,9% saline solution using anatomical landmarks and peripheral nerve stimulator; TIII - RP: ropivacaine 1% perineural administration using only anatomical land marks; and TIV - RN: ropivacaine 1% administration using anatomical landmarks and peripheral nerve stimulator to localization of the nerve roots. It was monitored heart rate (HR), respiratory rate (FR), systolic (SAP), mean (MAP) and diastolic arterial pressure (DAP), body temperature (T) and expired CO2 (ETCO2)) and isoflurane (ETISO) concentrarion. Increase in HR and/or SAP and/or MAP in 20% of baseline were characterized as the need for “rescue” analgesia with fentanyl (5 μg/kg - IV). The analysis of variance test was used, followed by Tukey’s multiple comparison test. The null hypothesis (no differences between treatments) was reject when P < 0.05. The block with... (Complete abstract click electronic access below)
27

Tratamento das fraturas com traço simples da diafise do femur, com tecnica minimamente invasiva e placa em onda / Treatment of simple femoral shaft fracture with minimally invasive technique and wave plate

Angelini, Alessandro Janson 31 August 2006 (has links)
Orientador: William Dias Belangero / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-08T02:22:20Z (GMT). No. of bitstreams: 1 Angelini_AlessandroJanson_D.pdf: 8473233 bytes, checksum: 3996290e908ef6f361b3a4bf25baf1d9 (MD5) Previous issue date: 2006 / Resumo: A partir de resultados de estudos mecânicos com a placa em onda, demonstrando sua maior rigidez em montagens com algum tipo de contato cortical, surge este estudo com o objetivo de analisar o desempenho desse tipo de placa no tratamento das fraturas de traço simples da diáfise do fêmur. Foram incluídos, retrospectivamente, 57 pacientes, consecutivos, tratados com a placa em onda com técnica de osteossíntese biológica, com seguimento mínimo de um ano de pós-operatório. Obteve-se índice de consolidação de 94,74% (54 em 57 pacientes) em tempo médio de 12,88 semanas. Conclui-se que o método pode ser considerado uma alternativa às hastes intramedulares, com índices de consolidação semelhantes / Abstract: Mechanical studies with wave plates, were a higher rigidity was shown in models with cortical contact, suggested a study to analyze the use of wave plate in femoral simple shaft fractures. A consecutive series of 57 patients treated with wave plates and biological internal fixation, and a minimal follow up of 1 year after surgery. Healing occurred in 94,74% (54 of 57 patients) with an average of 12 weeks. In conclusion, this method could be considered an alternative to intramedullary nailing, with similar success rates / Doutorado / Cirurgia / Doutor em Cirurgia
28

Análise topográfica através de análise metalográfica de placa e parafuso do sistema 2,4mm com sistema de travamento em três diferentes quantidades de ciclos de autoclavagem / Topographical analysis via metallographic analysis of plate and screw system of 2.4 mm locking system in three different cycles of autoclaving

Santos, Saulo Ellery, 1983- 03 January 2012 (has links)
Orientador: Roger William Fernandes Moreira, Marcelo Marotta Araujo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-20T05:38:06Z (GMT). No. of bitstreams: 1 Santos_SauloEllery_D.pdf: 17593176 bytes, checksum: 114d3bc8c68cd4b332a698a936817b96 (MD5) Previous issue date: 2012 / Resumo: Sistemas de fixação interna estável são utilizados em cirurgia óssea, sejam elas de fraturas ou osteotomias programadas, podem ser submetido a múltiplos procedimentos de esterilização procedimentos antes da implantação em um ambiente de acolhimento. Durante a sua utilização eventualmente o cirurgião depara-se com intercorrências cirúrgicas como quebra da placa durante a dobragem ou quebra de parafusos durante sua inserção e isso de fato ocorre na prática clínica. O objetivo do autor neste estudo foi avaliar se o processo repetido de autoclavagens influencia nas características de dureza e microscópicas das placas e parafusos do sistema 2,4mm "locking". A amostra foi dividas em placas: grupo I (0) controle, grupo II submetido a 20 processos de autoclavagem e grupo III submetido a 60 processos de autoclavagem. Os parafusos foram divididos da mesma forma: grupo I (0), grupo II (20) e grupo III (60). Após o preparo do corpo de provas foram realizados os testes de dureza e avaliação em microscopia da microestrutura. Encontrou-se uma média de valores de dureza de 180,2; 183,8 e 171,8 Vickers respectivamente para os grupos I, II e III das placas (p=0,497) e os valores médios de 328,8; 340,8 e 355,3 Vickers respectivamente para os grupos I, II e III dos parafusos (p=0,283). Na análise microscópica tanto dos parafusos quanto das placas observou-se imagens em 500x que revelaram a microestrutura do material, com grânulos em conformações diferentes, de acordo com a margem analisada, observam-se ainda formação de maclas, principalmente na margem interna, o que pode ser decorrente de força de pressão/cisalhamento durante processo de usinagem, mas sem diferenças entre os grupos. Baseado nos resultados obtidos nas amostras estudadas, observou-se que o processo repetido de autoclavagens não alterou significativamente as características de dureza e microscópicas do material analisado / Abstract: Stable internal fixation systems are used in bone surgery, either fractures or osteotomies, It can be submitted to multiple procedures sterilization procedures before implantation. During its use eventually the surgeon is confronted with surgical complications such as rupture of the plate during bending or breakage of screws during insertion, and this in fact occurs in clinical practice. The aim of study was to evaluate if the repeated autoclaving influences the characteristics of hardness and microscopic of plates and screws of 2.4 mm system "locking". The sample was divided into plates: group I (0) control, group II was subjected to 20 sterilization processes and group III underwent 60 procedures for autoclaving. The screws were divided equally: group I (0), group II (20) and group III (60). After preparing the sample, and were carried out hardness testing and evaluation in the microscopy of microstructure. We found a mean hardness value of 180.2, 183.8 and 171.8 Vickers respectively for the groups I, II and III of the plates (p = 0.497) and mean values of 328.8, 340.8 and 355.3 Vickers respectively for the groups I, II and III of the screws (p = 0.283). Microscopic analyzes of both screws and the plates was observed images 500x revealed that the microstructure of the material, with granules in different conformations in accordance with the margin analyzed, there are still forming twinned, especially in the inset, which may be due to pressure force / shear during the machining process, but no differences between groups was observed. Based on the results obtained in all samples, it was observed that the repeated autoclaving does not significantly alter the characteristics of the material hardness and microscopic examination / Doutorado / Cirurgia e Traumatologia Buco-Maxilo-Faciais / Doutor em Clínica Odontológica
29

Computational multi-scale simulation of implant for bone fracture repair

Kidgell, Victoria L. January 2010 (has links)
No description available.
30

Avaliação mecanica in vitro da resistencia de parafusos reabsorviveis utilizados como fixação rigida de osteotomias sagitais em hemimandibulas de poliuretano / In vitro mechanical evaluation of absorbable screws used as rigid fixation in sagittal osteotomies of polyurethane hemimandible

Silva, Fabricio Moreira Serra e 12 November 2006 (has links)
Orientador: Renato Mazzonetto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-08T02:05:36Z (GMT). No. of bitstreams: 1 Silva_FabricioMoreiraSerrae_D.pdf: 1159089 bytes, checksum: 7abc958a2fb0b5fd88148906e4e519b5 (MD5) Previous issue date: 2006 / Resumo: O propósito deste estudo foi avaliar a resistência mecânica in vitro de parafusos reabsorvíveis e metálicos utilizados em fixação interna rígida de osteotomias sagitais em hemimandíbulas de poliuretano. Foram utilizados 60 parafusos reabsorvíveis a base de um copolímero poli(L-co-D,L Ác. Lático) 70:30; e 60 parafusos metálicos (Ti-6Al-4V), todos com 2mm de diâmetro e 12mm de comprimento. Quarenta réplicas de hemimandíbulas dentadas humanas a base de poliuretano rígido foram utilizadas como substrato. As hemimandíbulas foram seccionadas na região de ramo mandibular bilateral, simulando uma osteotomia sagital, e reposicionadas sem recuo ou avanço dos segmentos. Vinte hemimandíbulas foram fixadas com 3 parafusos reabsorvíveis bicorticais com disposição em ¿L¿ invertido, correspondendo ao grupo teste; e outras 20 hemimandíbulas foram fixadas com 3 parafusos metálicos com mesma disposição, correspondendo ao grupo controle. Utilizando máquina de ensaio universal Instron®, modelo 4411, foram selecionadas 10 hemimandíbulas de cada grupo para que fossem submetidas a teste de carregamento com ponto de aplicação de força em região de incisivo, e outras 10 hemimandíbulas de cada grupo, em região de molar. Os valores das cargas foram obtidos, em Kgf, no momento de deslocamento de 3mm e em pico máximo de carga. As médias obtidas foram analisadas por meio de teste F e teste t de student. Os parafusos reabsorvíveis e metálicos apresentaram resultados sem diferença estatisticamente significante / Abstract: The aim of this study was to evaluate the in vitro mechanical strength of absorbable and metallic screws used as internal rigid fixation in sagittal split ramus osteotomies in polyurethane hemimandible replicas. Sixty poly(L-co-D,L lactic acid) (70:30 ratio) copolymer absorbable screws and sixty metallic screws (Ti-6Al-4V) were used, all presenting a 2mm diameter and 12mm length. Forty rigid polyurethane human hemimandible replicas were used as test specimes and sectioned bilaterally in the mandible ramus simulating sagittal split ramus osteotomies. The segments were fixed without advancement or setback. Twenty hemimandibles were fixed with three bicortical absorbable screws in an inverted L-shaped configuration (test group); and twenty hemimandibles were fixed with three metallic screws in the same configuration (control group). Ten hemimandibles of the test and control groups were subjected to vertical loading at the incisal edge, and other ten hemimandibles of both groups were subjected to vertical loading at the molar edge, using an InstronTM servo hydraulic mechanical testing unit, model 4411. The load peak value and load values (Kgf) at the time of a 3mm displacement were recorded. The means were evaluated through F test and t-student test. Absorbable and metallic screws showed results without statistically significant difference / Doutorado / Cirurgia e Traumatologia Buco-Maxilo-Faciais / Doutor em Clínica Odontológica

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