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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.
551

Cervical muscle strength and motor control assessment using dynamometry and surface electromyography in women with migraine and chronic migraine: a controlled study / Avaliação da força máxima e do controle motor da coluna cervical pela dinamometria e pela eletromiografia de superfície em mulheres com migrânea e migrânea crônica: estudo controlado

Florencio, Lidiane Lima 08 February 2017 (has links)
Objectives: to verify if women with migraine present altered neck muscles function and altered muscle activity in comparison to non-headache subjects. Moreover, we aimed to identify if there is any relationship between neck muscles dysfunction and the chronicity of migraine attacks. Methods: women with migraine, stratified by episodic and chronic, and age-matched non headache women were the subject of the current thesis. Neck pain relateddisability was assessed by the Neck Disability Index. Neck muscles strength was assessed by a customized hand-held dynamometer. Myoelectrical signals of the sternocleidomastoid, anterior scalene, splenius capitis and upper trapezius were assessed using surface electromyography. Experimental conditions involved maximal isometric voluntary contractions in flexion, extension and lateral bending directions and; craniocervical flexion test, a low load test applied to verify deep cervical flexors ability to supply adequate cervical spine stability. Finally, identification of myofascial trigger points and head and cervical posture photogrammetric evaluation were made in order to be correlated to the muscles electrical activity in the craniocervical flexion test. Results: Although both groups presents high prevalence of neck related disability, subjects with chronic migraine are more likely to report neck related disability, especially the most disabling forms, than episodic migraine. Episodic migraine demonstrated to different neck muscle control only under maximal voluntary tasks. Chronic migraine presented alterations in comparison with controls at maximal conditions, i.e., lower extension force; more time to produce maximal force; greater antagonist coactivation and greater fatigability. During craniocervical flexion test, chronic migraine also differs from control group presenting greater activity of neck extensors. Presence of active trigger points in neck muscles and extended head posture can influence the neck muscles activity during the craniocervical flexion test. Conclusions: migraine is associated to a deterioration of neck muscles functions and to an altered motor control. We can assume an interaction between chronicity of migraine frequency and cervical dysfunction, specially related to neck extensors. More severe disabilities and the majority of the altered function or motor control could only be evidenced in the chronic form / Objetivos: verificar se mulheres com migrânea apresenta alteração na função e atividade dos músculos do pescoço quando comparados a mulheres sem cefaleia. Ainda, objetivamos identificar se há relação entre disfunção cervical muscular e a cronicidade da frequência de crises migranosas. Materiais e métodos: mulheres com migrânea, estratificada entre episódica e crônica, e mulheres sem cefaleia com idade semelhante foi o objeto de estudo dessa tese. Foi investigada a incapacidade relacionada à dor cervical pelo questionário Neck Disability Index e a força muscular cervical utilizando um dinamômetro manual customizado. Ainda, a atividade elétrica dos músculos esternocleidomastoideo, escaleno anterior, esplênio da cabeça e trapézio superior foi verificada pela eletromiografia de superfície. Os procedimentos experimentais foram contração isométrica voluntária máxima em flexão, extensão e inclinação lateral; e o teste de flexão craniocervical, que avalia a habilidade dos músculos flexores cervicais profundos em prover adequada estabilidade para esse segmento. Por fim, a identificação de pontos gatilhos nos músculos cervicais e a avaliação da postura da cabeça e do pescoço por foto foram realizadas a fim de correlacionar os achados com a atividade eletromiográfica. Resultados: embora ambos os grupos de migrânea tenham apresentado alta prevalência de incapacidade relacionada à dor cervical, a migrânea crônica apresenta maior risco de relatar incapacidades mais severas em relação a migrânea episódica. O grupo de migrânea episódica apresentou controle muscular cervical alterado em condição de contração voluntária máxima. Já o grupo migrânea crônica apresentou alterações sob condições máximas, como por exemplo, redução da força dos extensores, mais tempo para gerar pico de força em flexão e inclinação lateral, maior coativação do antagonista e maior susceptibilidade à fadiga. Ainda, durante o teste de flexão craniocervical, o grupo migrânea crônica apresentou maior atividade dos extensores indicando alteração no controle motor. A presença de pontos gatilhos nos músculos do pescoço e a postura em extensão de cabeça pode influenciar a atividade elétrica dos músculos cervicais durante a execução do teste de flexão craniocervical. Conclusões: a migrânea está associada a uma deteriorização da função e do controle motor cervical. Podemos assumir ainda que há uma interação entre a cronicidade da frequência das crises migranosas e a disfunção muscular cervical, especialmente relacionada aos extensores. Incapacidades mais severas e a maioria das disfunções musculares e alteração no controle motor só puderam ser evidenciadas para o grupo com migrânea crônica
552

The epidemiology of osteoporotic vertebral deformity in Chinese men.

January 1999 (has links)
by Chan Yat Heung. / Thesis submitted in: December 1998. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 81-88). / Abstract also in Chinese. / Declaration --- p.2 / Abstract --- p.3 / Abstract in Chinese --- p.5 / Acknowledgements --- p.7 / Chapter Chapter 1. --- Introduction --- p.12 / Chapter Chapter 2. --- Literature review on the prevalence of vertebral deformity --- p.16 / Chapter 2.1 . --- Prevalence of vertebral deformity in women --- p.16 / Chapter 2.2. --- Prevalence of vertebral deformity in men --- p.21 / Chapter Chapter 3. --- Literature review on the risk factors for osteoporosis and vertebral deformity --- p.25 / Chapter 3.1. --- Dietary calcium intake --- p.25 / Chapter 3.1.1 --- Epidemiological studies --- p.25 / Chapter 3.1.2 --- Intervention studies --- p.26 / Chapter 3.1.3 --- Calcium intake and osteoporosis in Chinese --- p.28 / Chapter 3.2. --- Physical Activity --- p.30 / Chapter 3.2.1 --- Epidemiological studies --- p.30 / Chapter 3.2.2 --- Intervention studies --- p.33 / Chapter 3.2.3 --- Physical activity and osteoporosis in Chinese --- p.34 / Chapter 3.3. --- Cigarette smoking --- p.35 / Chapter 3.4. --- Alcohol consumption --- p.37 / Chapter Chapter 4. --- Subjects and Methods --- p.39 / Chapter 4.1. --- Objectives --- p.39 / Chapter 4.2. --- Study Subjects --- p.40 / Chapter 4.3. --- Radiology and digitization protocol --- p.41 / Chapter 4.4. --- Diagnosis of vertebral deformity --- p.43 / Chapter 4.5. --- Definition of cases and controls --- p.48 / Chapter 4.6. --- Questionnaire and measurement of risk factors --- p.49 / Chapter 4.6.1. --- Dietary calcium intake --- p.49 / Chapter 4.6.2. --- Physical activity --- p.49 / Chapter 4.6.3. --- Cigarette smoking --- p.50 / Chapter 4.6.4. --- Alcohol consumption --- p.50 / Chapter 4.7. --- Pilot study --- p.51 / Chapter 4.8. --- Statistical methods --- p.52 / Chapter Chapter 5. --- Results of Prevalence study --- p.54 / Chapter 5.1 . --- Demographic characteristics --- p.54 / Chapter 5.2. --- Vertebral height and vertebral height ratio --- p.55 / Chapter 5.3. --- Distribution of deformity --- p.59 / Chapter 5.4. --- Comparison of prevalence between Chinese and Caucasian populations --- p.61 / Chapter Chapter 6. --- Results of study on risk factors --- p.62 / Chapter 6.1. --- Dietary calcium intake --- p.62 / Chapter 6.2. --- Physical activity --- p.63 / Chapter 6.3. --- Cigarette smoking --- p.65 / Chapter 6.4. --- Alcohol consumption --- p.67 / Chapter 6.5. --- Results of Multiple logistic regression --- p.69 / Chapter Chapter 7. --- Discussion --- p.70 / Chapter 7.1. --- Study sample --- p.70 / Chapter 7.2. --- Digitization method and definition of vertebral fracture --- p.71 / Chapter 7.3. --- Prevalence of vertebral deformity in Chinese men --- p.72 / Chapter 7.4. --- Risk factors --- p.74 / Chapter 7.4.1. --- Calcium intake --- p.74 / Chapter 7.4.2. --- Physical activity --- p.75 / Chapter 7.4.3. --- Cigarette Smoking --- p.77 / Chapter 7.4.4. --- Alcohol consumption --- p.78 / Chapter Chapter 8. --- Conclusion --- p.80 / Reference --- p.81 / Appendix --- p.89
553

Quantitative Anatomie zweier Formen von dendritischen Dornfortsätzen an hippocampalen Pyramidenzellen / Quantitative anatomy of two shapes of dendritic spines from hippocampal pyramidal cells

Koerbs, Christina 11 March 2019 (has links)
No description available.
554

Qualidade de vida relacionada à saúde e expectativas de pacientes antes do tratamento cirúrgico da estenose lombar / Quality of life related to health and expectations of patients before surgical treatment of lumbar stenosis

Lilian Maria Pácola 07 August 2013 (has links)
As doenças que provocam a estenose da coluna lombar têm contribuído para a piora da qualidade de vida, ocasionando dor e limitações funcionais em uma parcela considerável da população ativa. O tratamento cirúrgico da estenose geralmente é indicado quando ocorre déficit neurológico progressivo, resistente ao tratamento conservador e se a doença apresenta impacto na qualidade de vida do paciente. A carência de pesquisas nacionais já publicadas sobre o tema, principalmente aquelas com enfoque na avaliação subjetiva desses indivíduos nos motivou a realização deste estudo observacional e analítico, de delineamento transversal. O objetivo foi avaliar as expectativas e a associação da qualidade de vida relacionada à saúde (QVRS) com a presença de sintomas de ansiedade e depressão em pacientes que aguardavam o tratamento cirúrgico da Estenose do Canal Lombar. A amostra foi composta por pacientes com indicação cirúrgica de estenose lombar, atendidos entre agosto de 2011 e novembro de 2012, em um hospital geral público de ensino. Os dados foram coletados por entrevistas individuais e consulta aos prontuários dos participantes. As variáveis de interesse foram mensuradas por instrumentos específicos e previamente validados. A QVRS foi avaliada pelo Índice de Incapacidade de Oswestry e pelo SF-36. Os sintomas de ansiedade e depressão foram avaliados segundo as subescalas do Hospital Anxiety and Depression Scale (HADs). As expectativas frente ao tratamento cirúrgico da estenose foram investigadas por questões previamente usadas em estudos internacionais. Os dados foram analisados descritivamente, e o teste t de Student foi utilizado para amostras independentes e realizado para comparar as médias das variáveis de interesse, segundo a presença de sintomas de ansiedade ou depressão. O nível de significância adotado foi de 0,05. Participaram da investigação 38 pacientes, sendo 32 (84,2%) com diagnóstico de estenose lombar, três (7,9%) com espondiloartrose, dois (5,3%) com estenose lombar/listese e um (2,6%) apresentava diagnóstico de discopatia. O tempo médio de evolução da doença foi de 38,3 meses. A média de idade foi 60,4 anos, e 63,2% eram mulheres. Na avaliação da QVRS, pelo SF-36, os domínios mais comprometidos foram aqueles relacionados às atividades físicas como Aspectos físicos (M=4,61; D.P.=11,4) e Capacidade funcional (M=25,8; D.P.=11,4) e os mais bem avaliados foram Estado geral de saúde (M=73; D.P.=12,5) e Saúde mental (M=63,8; D.P.=17,2). A média do ODI obtida entre os participantes foi de 50,9%. A classificação dos participantes mostrou que 55,3% apresentavam incapacidade grave, 23,7%, incapacidade moderada e 21,1%, invalidez. Sintomas de ansiedade e de depressão estavam presentes, respectivamente, em 31,6% e 10,5%. Comparando os valores médios dos domínios do SF-36, segundo a presença ou não desses sintomas, em sete dos oito domínios, o grupo com sintomas apresentou médias menores do que o grupo sem sintomas, indicando pior QVRS. Entretanto, as diferenças entre os grupos foram estatisticamente significantes apenas para o domínio Estado geral de saúde, considerando a presença de ansiedade, e para o domínio Saúde mental quando os grupos foram comparados segundo a presença de sintomas de depressão. Na avaliação das expectativas, 47,4% dos participantes esperavam ficar \"Muito melhor\" com relação à dor nas pernas, capacidade de caminhar e independência das atividades diárias. Embora com limitações, o presente estudo, contribuiu para a prática clínica, uma vez que pode ampliar o conhecimento sobre os pacientes com estenose lombar. Diante da nossa prática clínica, consideramos que as expectativas referidas pelos pacientes frente ao tratamento cirúrgico nem sempre podem ser satisfeitas. Assim, os enfermeiros, entre outros profissionais que cuidam destes pacientes, precisam se responsabilizar por uma orientação mais clara e objetiva, voltada às reais possibilidades advindas da cirurgia para a melhora da qualidade de vida. A presença de sintomas de ansiedade e depressão também deve ser considerada como relevantes no pré-operatório destes indivíduos. / The diseases that cause stenosis of the lumbar spine have contributed to the worsen the quality of life and cause pain and functional limitations in a considerable portion of the working population. Surgical treatment of stenosis is usually indicated in case of progressive neurological deficit, resistance to conservative treatment and when the disease has an impact on quality of life of the patient. The lack of national researches already published on the subject, especially those focusing on the subjective evaluation of those individuals, motivated us to conduct this observational and analytical study, cross-sectional design. The objective was to evaluate the association of expectations and the Health-Related Quality of Life (HRQoL) with symptoms of anxiety and depression in patients awaiting surgical treatment of lumbar stenosis. The sample was consisted of patients with surgical indication for lumbar stenosis, treated between August 2011 and November 2012, in a hospital of public teaching. Data were collected through individual interviews and hospital records of participants. The variables of interest were measured by specific instruments, previously validated. HRQoL was assessed by the Oswestry Disability Index and the SF-36. Symptoms of anxiety and depression were assessed by the subscales of the Hospital Anxiety and Depression Scale (HADS). Expectations for the surgical treatment of stenosis were investigated by questions previously used in international studies. Data were analyzed descriptively and the Student t test for independent samples was performed to compare the means of the variables of interest, according to the presence of symptoms of anxiety or depression. The significance level was 0.05. 38 patients participated in the study, 32 (84.2%) with a diagnosis of lumbar stenosis, three (7.9%) espondiloarthrosis, two (5.3%) lumbar stenosis / listese and one (2.6%) had been diagnosed of discopathy. The duration of disease was on average 38, 3 months. The mean age was 60.4 years and 63.2% were women. In the assessment of HRQOL by SF-36, the amost affected areas were those related to physical activities like physical aspects (M = 4.61, SD = 11.4) and functional capacity (M = 25.8, SD = 11, 4) and areas with better evaluation were General health (M = 73, SD = 12.5) and Mental health (M = 63.8, SD = 17.2). The average of ODI obtained among participants was 50.9%. The classification of the participants showed that 55.3% had severe disability, 23.7% moderate disability and 21.1% invalidity. Symptoms of anxiety and depression were present, respectively, in 31.6% and 10.5%. Comparing the mean values of the SF-36 in the presence or absence of these symptoms, in seven of the eight domains, the group with symptoms showed lower average than the group without symptoms indicating worse HRQOL. However, the differences between the groups were statistically significant only for the domain general health, considering the presence of anxiety, and for the domain mental health when the groups were compared according to the symptoms of depression. In evaluating the expectations, 47.4% of respondents were expected to be \"much better\" about leg pain, walking ability and independence of activities daily. Even with limitations, this study has contributed to the clinical practice, since it can increase knowledge about patients with lumbar stenosis, we believe that the expectations reported by patients about surgical treatment can not be always satisfied. Thus, nurses, and other professionals who care for these patients need to take responsibility for clearer and objective guidance, oriented for the real possibilities arising from the surgery to improve the quality of life. The presence of symptoms of anxiety and depression should also be considered as relevant preoperatively these individuals.
555

Estudo biomecânico ex vivo em coluna tóraco-lombar de cães com técnicas de estabilização utilizando Placa Bloqueada, Clamp Rod Internal Fixation, Pino com Cimento Ósseo e Técnica Segmentar Modificada / Ex vivo biomechanical evaluation of the canine thoracolumbar spines with techniques of stabilization using Locking Plate, Clamp Rod Internal Fixation, Pins with Bone Cement and Modified Segmental Instrumentation

Figueiredo, Adriana Valente de 18 October 2013 (has links)
Fraturas e luxações vertebrais decorrente de trauma consistem afecção neurológica frequente na prática clínica veterinária, sendo a coluna tóraco-lombar a mais comumente afetada em cães, e em muitos casos o tratamento cirúrgico é de eleição. Existem diversas técnicas propostas a realizar estabilização vertebral, entretanto, estudos em coluna tóraco-lombar não foram realizados para avaliar as propriedades biomecânicas de cada técnica. Baseado nisso, nossa pesquisa teve como objetivo fazer uma avaliação biomecânica comparando a força e rigidez promovidas por cinco diferentes técnicas de estabilização em coluna toracolombar (Pinos com Cimento Ósseo, Técnica Segmentar Modificada, Placa Bloqueada e Clamp Rod Internal Fixation utilizando parafusos monocorticais e bicorticais) frente às forças de compressão e flexão. Foram utilizadas 34 colunas tóraco-lombares de cães, divididas em cinco grupos. Para realização dos testes biomecânicos, foi utilizada a máquina de ensaios Kratos (modelo KE3000MP) e célula de carga de 100 kg. Para cada corpo de prova, três testes biomecânicos foram realizados, o controle, no segmento íntegro, após desarticulação de T13/L1 e após realização de uma das técnicas de estabilização propostas. Os dados foram exportados para análise estatística para o programa Statistical Package for the Social Sciences (SPSS) versão 18.0. Os resultados permitiram concluir que, apesar de não haver diferença estatística significativa, a Placa Bloqueada foi a técnica que promoveu maior rigidez e estabilidade nas vértebras lesionadas, seguida do CRIF bicortical, técnica Segmentar Modificada e Pinos e Cimento Ósseo. Estatisticamente, a Placa Bloqueada e o CRIF com parafusos bicorticais apresentaram maior rigidez e estabilidade em T13/L1 quando comparados com a técnica CRIF monocortical, que por sua vez, não alcançou rigidez necessária para adequada estabilização das vértebras. / Spinal fractures and luxations resulting from trauma consist frequent disorder in clinical veterinary practice, being thoracolumbar spine the region that is the most commonly affected in canines, thus in many cases surgical treatment is necessary. There are several proposed techniques of implants to perform spinal stabilization; however, few studies of the thoracolumbar spine were carried out to evaluate the biomechanical properties of each technic. Therefore, the objective of the present study is to analyze biomechanical effects comparing the strength and the stiffness promoted by five different technics of stabilization in the thoracolumbar spine (pin with bone cement, modified segmental stabilization, locking plate and clamp rod internal fixation) under compression and bending forces. In the study, thirty four thoracolumbar dog spines were used, dividing the specimens in five groups. In order to perform the biomechanical tests, it was used a Kratos testing machine (model KE3000MP) and loading cell of 100 Kg. Each body of proof was submitted to three biomechanical tests, the control, in the segment intact, after disarticulation of the T13/L1 and after the realization of one of the proposed technics. Data were exported to statistical analyses to the Statistical Package for the Social Sciences (SPSS) version 18.0. The results led to the conclusion that despite there was no statistically significant difference between the techniques, the Locking Plate was the technique that promoted greater rigidity and stability in the injured vertebrae, followed by the Clamp Rod Internal Fixation bicortical, Modified Segmental Instrumentation and Pins with Bone Cement. Statistically, the locking plate and the Clamp Rod Internal Fixation with bicortical pins showed more stiffness and stability in T13/L1 when compared to the Clamp Rod Internal Fixation monocortical, which did not achieved the adequate rigidity for the stabilization of the vertebrae.
556

Chirurgické možnosti léčby degenerativního onemocnění thorakolumbální páteře: Význam morfologických a klinických klasifikací stenózy bederní páteře v předoperační rozvaze / The Surgical Treatment Options in Thoracolumbar Spine Degeneration: The Importance of Morphological and Clinical Classifications in Preoperative Decision Making

Bludovský, David January 2019 (has links)
The surgical treatment options in thoracolumbar spine degeneration: The importance of morphological and clinical classifications in preoperative decision making David Bludovský Abstract: Objective: The aim of our study was to investigate the relations between subjective difficulties, clinical findings and the MR imaging in patients who have been operated for symptomatic lumbar spinal stenosis (LSS), and the possibility of using these relations for surgical treatment decision. Methods: Patients operated for lumbar spinal stenosis in 2009-2010 were included in the study. Subjective difficulties were assessed using the Oswestry Disability Index (ODI), the clinical symptoms with the modified Neurological Impairment Score for Lumbar Spinal Stenosis (mNIS-LSS). We measured the spine canal area, dural sac area, and nerve root sedimentation classification on MR. By correlation analysis at significance level p <0.05, we tested the relations between these categories. 61 patients with a median age of 67 were included. Overall, we evaluated 162 spinal segments. Results: Median of ODI values were 48. Correlation coefficients for ODI, mNIS-LSS and graphical findings were less than 0.5. Correlation coefficients greater than 0.5 were between all the MR measurement methods. Conclusions: In the group of patients indicated...
557

Estudo da Participação do Osso Cortical e Esponjoso na Fixação de Implante Pedicular na Coluna Lombar. / Mechanical and histological studies of the vertebral screw interface

Vendrame, José Roberto Benites 28 April 2000 (has links)
Foi realizado estudo experimental com a finalidade de avaliar a participação do osso cortical e osso esponjoso dos pedículos vertebrais, na fixação dos parafusos pediculares. Foram utilizados 10 segmentos de coluna lombar de adultos, retirados durante autópsia. O diâmetro dos pedículos das vértebras de L1 a L5 foram avaliados, considerando o diâmetro total e o diâmetyro do osso esponjoso, tendo sido realizadas essas medidas por meio de tomografia computadorizada e medida direta. Os segmentos da coluna vertebral foram divididos em dois grupos para o estudo, sendo que cada grupo era formado por 5 conjuntos de segmentos da coluna lombar. No primeiro grupo a perfuração era realizada segundo os pontos de orientação utilizados nos procedimentos cirúrgicos ( faceta articular e processo transverso). No segundo grupo foi realizado corte transversal na porção média do pedículo, de modo que a perfuração e introdução dos parafusos no seu interior foram efetuados sob visão diereta. Após a perfuração dos pedículos utilizando-se broca de 3 mm, os parafusos eram introduzidos no interior do pedículo vertebral em ordem crescente de seus diâmetros, até que fosse observada alteração estrutural do pedículo, que eram avaliados por meio de medidas sucessivas, utilizando-se paquímetro e observação direta. Foram utilizados parafusos com diâmetro que variou de 3 a 12,5 mm, com progressão de 0,5 mm. Quando o diâmetro do parafuso excedia a resistência estrutural do pedículo, duas lesões foram observadas, a deformação plástica e o rompimento. No grupo I houve um número maior de deformação plástica, mas pelos cálculos estatísticos não houve diferença significativa entre os grupos. Os diâmetro tomográficos obtidos pela medida tomográfica e medida direta apresentaram-se diferentes e sem correlação entre si. No grupo II, como os parafuos foram introduzidos de modo mais centralizado, houve maior número de parafusos com diâmetro maior que o diâmetro do osso esponjoso, mas também não apresentou diferença entre os grupos, segundo avaliações estatísticas. Análise dos valores do diâmetro pedicular, diâmetro do osso esponjoso e do parafuso de maior diâmetro introduzido sem lesar o pedículo permitiu observar que a camada de osso cortical do pedículo foi pouco ocupada pelo parafuso em ambos os grupos. O valor médio da porcentagem do diâmetro do pedículo ocupado pelo parafuso no grupo I foi de 70,7% e no grupo II 75,34%. Foi observado que os parafusos, de um modo geral, apresentaram ancoragem principalmente na porção de osso esponjoso do pedículo vertebral, tendo sido pequena a porcentagem de osso cortical do pedículo vertebral utilizado para a sua ancoragem. / Spine surgery has developed a lot in the last years because of the evolution of the fixation system. The behavior of a screw in the bone is still unknown in many ways. Because the screw is the anchor of sustentation, this work tries to find the answers involving the pedicle screw fixation. To reach this objective we developed this work based on mechanical and histological studies. Two kinds of pedicle screws were used: pedicle screw of the USIS (Ulrich) and pedicle screw of the USS system (Synthes). The pullout tests were made in wood and polyurethane. The histological study was done in lumbar vertebra of humans. In the study about the USIS screw, the follow parameters were tested: hole done with probe and hole done with drill, all of the same inner diameter of the screw. The effect of tapping and not tapping the hole done with drill was tested. In the USS screw study, the effect of the diameter pilot hole in the pullout tests and its historical analysis was seen. In the pullout tests of these screws, both kind of holes done with probes and a drill were tested. The work was divided into stages; first stage was the study of the pullout of the USIS screw; second stage was two studies, a light-microscopic one and a sweeping-electronic-microscope one of the slides of the instrumented vertebra with USIS screws; third stage was the study of the USS screws pullout comparing the relationship between the diameter of the holes and the inner diameter of the screw together with the type of hole (drill and probe); fourth stage was light-microscopic histological study of the instrumented vertebras which had had USIS screws. Results of the first stage showed that probes were more efficient than drills because the mechanical tests of pullouts from probe-made-holes showed the need of the use of a stronger force. In the second stage, a light-microscopic analysis showed that probe-made-holes had a lesser minimum diameter and a lower index of fragmentation than drill-made holes. With relation to the tapping, there was no difference between the holes. Under electronic microscope sweeping, it was seen that probes betters compact the bone around the screw. In the third stage, it was seen that when the pilot orifice was greater than the screws internal diameter a significantly lower force was needed for pullout, while when the pilot orifice was smaller it did not significantly increase the force needed. It was also seen that probe-made-holes had a better anchorage than the drill-made-holes. In the fourth stage, the histological analysis of the slides done with light-microscopy showed that the smaller the diameter of the drill the smaller minimum diameter; there was no significant difference between fragmentation indexes. Conclusion: Probes are better than drills to make a pilot hole because they cause less damage to the surrounding bone and give a stronger anchorage for the screw; the smaller the instrument used to make the pilot hole, better will be the strength of the screw\'s anchorage; the critical point which the hole must not exceed is the internal diameter of the screw. Tapping, or not, makes no difference to the anchorage.
558

Clinical Significance of Response Shift in a Spine Interventional Clinical Trial

Carlson, Robin 01 January 2015 (has links)
The effectiveness of treatments for degenerative spine conditions, where the primary symptom is back pain, is typically determined using patient-reported quality of life (QoL) measures. However, patients may adjust their internal standards when scoring QoL based on factors other than their health. This response shift phenomenon could confound the interpretation of study data and impact effectiveness conclusions. In the current study, response shift was examined using structural equation modeling (SEM) and previously collected clinical trial data comparing 2 minimally invasive medical devices in lumbar spinal stenosis patients through 1 year postintervention. In subject QoL results, reprioritization shift between 3 months and 12 months that could confound standard analysis was identified. Treatment group did not influence response shift identified at 12 months. SEM provided an effective and practical tool for clinical investigators to assess response shift in available clinical study data. As response shift could lead to invalid conclusions when QoL measures are analyzed, clinical investigators should include response shift assessment in the design of clinical trials. This research into how response shift phenomenon can impact clinical trial results improves the ability of clinical investigators to interpret clinical trial data, potentially preventing erroneous conclusions. This research may also assist researchers and government regulators in the identification and reimbursement of beneficial, cost-effective medical treatments for patients worldwide. For clinical research designers, this study demonstrates a practical application of response shift assessment.
559

Bestimmung des Einflusses verschiedener Operationsverfahren auf das mechanische Verhalten der Lendenwirbelsäule

Zander, Thomas 20 July 2004 (has links)
Der Erfolg einer operativen Behandlung der Lendenwirbelsäule hängt von mehreren oft unbekannten Faktoren ab. Einen möglichen unbekannten Faktor stellen mechanische Größen dar, welche in In-vivo-Studien nur teilweise messbar oder in In-vitro-Versuchen nur eingeschränkt aussagefähig sind. Hier stellt die Finite-Elemente-Methode eine reproduzierbare numerische Möglichkeit dar, den mechanischen Einfluss verschiedener Operationsverfahren a priori zu ermitteln. In dieser Arbeit ist ein Finite-Elemente-Modell der Lendenwirbelsäule erstellt worden, welches mit Hilfe vorhandener Ergebnisse aus In-vivo- und In-vitro-Untersuchungen validiert werden konnte und das die Simulation verschiedener Operationsverfahren ermöglicht. Weiterhin wurde eine Methode zur Abschätzung der Muskelkräfte entwickelt, die eine realistischere Belastung des Modells erlaubt als bisher üblich. Die Anwendung des Modells erstreckte sich in dieser Arbeit auf Dekompressionsverfahren zur Entlastung des Spinalkanals und Fusionsverfahren zur Herstellung der lumbalen Stabilität. Der Einfluss der Variation verschiedener Modell- und Operationsparameter wurde ermittelt. Hierzu zählen insbesondere die Steifigkeiten der Bänder, der Resektionsgrad bei der Dekompression des Spinalkanals und die unterschiedlichen Charakteristika des für die Fusion nötigen Knochenspans. Die Ergebnisse erweitern das biomechanische Verständnis der Wirbelsäule und geben Aufschluss über die Einflüsse wichtiger Operationsparameter. / The success of a surgical treatment at the lumbar spine depends on several, often unknown, factors. Mechanical values are one possible unknown factor. During in vivo studies these values are often not measurable and their relevance during in vitro experiments is limited. The finite element method is a reproducible numerical method which allows to determine the mechanical influence of different surgical techniques a priori. A finite element model of the lumbar spine has been created in this study. It was validated with existing values from in vivo and in vitro investigations and therefore makes the simulation of surgical techniques possible. Additionally, a method to estimate muscle forces was created. This method allows a more realistic loading of the model than usual. In this study, the model was used to simulate decompressional procedures to release the spinal cord and fusional techniques to regain lumbar stability. The influence of variations in model and surgical parameters on the mechanical behaviour was determined. In particular, the effects of ligament stiffness, the degree of decompression and different bone graft characteristics was determined. The results extend biomechanical knowledge about the spine and reveal the influence of important surgical parameters.
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Acupuncture for Quality of Life in Patients Having Pain Associated with the Spine: a Systematic Review

Lu, Shao-chen, ILLEGIBLE January 2008 (has links)
Background: Pain associated with the spine (PAWS) refers to pain in the neck, thorax, lower back or sacrum. It impacts on patients' Quality of Life (QoL), including working ability, daily functioning, sleep and psychological well-being. A number of clinical trials have demonstrated that acupuncture was beneficial for patients with PAWS. However the overall effect of acupuncture on these patients' QoL is unknown. Aims: The current study aimed to conduct a systematic review (SR) of clinical trials to determine the effect of acupuncture on QoL and pain for patients with PAWS. In addition, a narrative review (NR) was conducted to compare patients' perceived changes (PCC) with the standard QoL instruments used in acupuncture clinical trials for pain. Methods: For the SR, PubMed, Embase (via ScienceDirect), CINAHL (Via EBSCO) and Cochrane Central Register of Controlled Trials were searched. Randomised controlled trials (RCTs) of acupuncture for PAWS condition(s) that include both QoL and pain assessments with a Jadad score of three or greater were included. For the NR, PubMed was searched to identify studies reporting PPC after acupuncture and/or traditional Chinese medicine. Extracted data were grouped and compared with domains of the QoL instruments. Results: In total, 21 RCTs were included and 17 of them had sufficient data for analysis. QoL was measured using 15 different instruments. Randomisation procedures and dropouts were adequately reported in all 17 studies. Four studies compared acupuncture with wait-list or usual-care. Two demonstrated that acupuncture had a superior effect on improving physical and mental components of QoL measured by Short Form-36 health survey questionnaire and pain at the three month follow-up. Studies comparing acupuncture with sham/placebo acupuncture or placebo-TENS found either no difference between the treatments or conflicting results. When acupuncture was compared with active interventions, there was no difference except that at the intermediate-term follow-up massage was better for disability and pain and physiotherapy was better for Northwick Park Neck Pain Questionnaire. Acupuncture was also better than TENS for pain. The combined therapy of acupuncture and an active intervention showed a superior result than the latter alone in the short-term. Six studies were identified for the NR. Patients reported 11 categories of changes after acupuncture, such as reduced reliance on other therapies, enhanced spirituality, prevention of disease. However, these clinical outcomes were not included in any of the QoL instruments used in the included RCTs. Conclusion: There is moderate to strong evidence that acupuncture is more effective than wait-list or usual-care at the short-term follow-up in improving QoL of patients with PAWS. When acupuncture is combined with another therapy, the combined therapy seems to produce a better outcome. Acupuncture is not better than sham/placebo acupuncture or placebo-TENS. Surprisingly, the commonly used QoL instruments do not measure all the changes perceived by patients as a result of acupuncture and/or traditional Chinese medicine. There is a pressing need to design QoL assessments that are suitable for acupuncture research. Further studies should have larger sample sizes and additional validated outcome assessments are required to detect effects of acupuncture.

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