161 |
Progressive Disc Herniation: An investigation of the mechanism using histochemical and microscopic techniquesTampier, Claudio January 2006 (has links)
Abstract Background: The process that involves the migration of the nucleus pulposus from the innermost annular layers and culminates with the final extrusion of the nucleus has been limited to a few studies. This investigation was directed towards a better understanding of the herniation process. The architecture of the annulus fibrosus and the mechanism of progressive disc herniation were analyzed, using a controlled porcine model. Microscopic and histochemical techniques were employed. <br /><br /> Methodology: Two studies were performed. In the first stage, the macroscopic and microscopic structures of twelve cervical intervertebral discs were compared with young human disc data from studies reported in the literature. Important structural features were studied such as annulus fibrosus thickness, number of lamellae, lamellae thickness, orientation of the lamellae fibers and blood supply. In the second study, sixteen fresh-frozen functional spine units were submitted to repetitive flexion?extension motions combined with a low compressive load in a servo-hydraulic dynamic testing system. Discograms, dissections and histochemical techniques were applied to characterize the cumulative damage. The experiment produced eight complete herniations, four partial herniations and four specimens without any microscopic detectable annular damage. <br /><br /> Results and Discussion: The structure of the cervical porcine disc resembles the lumbar human disc. Some differences are evident. The size of the annulus is smaller, the thickness of the lamellae is narrower and the number of layers is fewer in the pig. It is hypothesized that the flexion-extension motion combined with a low-level load produced an increased hydraulic pressure in the inner wall of the posterior annulus. This pressure and repetitive motion first produced a small cleft, spreading the collagen bundles inside the first layer. The nuclear material was "pumped" through the small cleft to the first layer filling the layer creating a fluid-filled pocket between the collagen fibers. Once the "pocket" acquired enough pressure a new cleft was produced in the weakest part of the layer allowing the nuclear material to create a new "pocket" in the second layer. This was the first stage of damage and disc herniation production. This mechanism was repeated until the nucleus traveled along the annulus reaching the posterior longitudinal ligament. At this point a complete extrusion herniation was produced. <br /><br /> Conclusion: The porcine model appears to be suitable as a model to understand the mechanism of disc herniation when the spine is subjected to flexion-extension motions combined with a low-level load. The first cumulative injury appears to be a cleft between the lamellae bundles produced by the nuclear hydraulic pressure. A cumulative load/cumulative injury model approach was used to create the damage that was quantified in the study.
|
162 |
The effect of differing clinical settings on chiropractic patients suffering from mechanical low back painRichardson, Grant Walter January 2007 (has links)
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban University of Technology, 2007. / Each healing encounter, and every treatment, has specific and non-specific treatment effects. Non - specific effects, or placebo effects, are the benefits felt by the patients because of the nature of the healing encounter. Although difficult to quantify and control, a number of authors recognize that the non-specific component of management has an additive effect on the overall clinical outcome. It has been reported that due to the physical interaction and social nature of chiropractic, there is a strong non-specific component in the management process, but to what extent it facilitates in the healing encounter is unknown. It has also been shown that spinal manipulation has a clinical effect which exceeds that of placebo; therefore it is possible for its effect to be muted or amplified, depending on the presence or absence of non-specific effects. For the above reasons this study was conducted in an attempt to map the size of the nonspecific effect in the healing encounter by manipulating the practice setting in which the patients were treated. This was achieved using a prospective, randomised, comparative clinical experiment consisting of 60 individuals with Low Back Pain (LBP), selected by convenience sampling. Individuals were then divided into 2 groups of 30. The IV first group's treatment consisted of the standard diversified method of manipulation in a Clinical Research Setting, and the second group received the same treatment except the treatment took place in a Normal Practice Setting. / M
|
163 |
Effectiveness of proprioceptive neuromuscular facilitative stretching combined with administration of Diclofenac compared to proprioceptive neuromuscular facilitative stretching and placebo medication for the treatment of cervical facet syndromeUpneck, Heidi Sian January 2001 (has links)
Dissertation submitted to the Faculty of Health in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Technikon Natal, 2001. / The purpose of this study was to test the Effectiveness of Proprioceptive Neuromuscular Facilitative Stretching combined with administration of Diclofenac compared to Proprioceptive Neuromuscular Facilitative Stretching and placebo medication for the treatment of Cervical Facet Syndrome in a clinical experimental setting. Neck pain is a common disorder, which can often be attributed to mechanical dysfunction of the cervical spine. The patient with facet syndrome may complain of sudden onset of unilateral neck pain, often with referred pain. Muscle spasm is usually present causing restricted movement. Pain increases with movement and is relieved by rest. The pain is aggravated by hyperextension and relieved by flexion and often follows a sclerotomal rather than a dermatomal pattern. Forty subjects with mechanical neck pain were screened for facet syndrome and randomly divided into two groups of twenty. Each patient received Proprioceptive Neuromuscular Facilitative (PNF) stretching of the Posterior Cervical and Trapezius musculature. In conjunction with this, half the patients received Cataflam D while the other half received placebo medication. The patients were treated five times over a period of two weeks. Both groups were evaluated in terms of subjective and objective clinical findings by making use of questionnaires (Numerical Pain Rating Scale 101, Short Form McGill Pain Questionnaire and the CMCC) and algometer and goniometer measurements respectively. The data was collected at the initial, middle and final treatments for each patient. / M
|
164 |
Dendritic Spine Density Varies Between Unisensory and Multisensory Cortical RegionsBajwa, Moazzum 07 May 2010 (has links)
In the brain, the dendritic spine is a point of information exchange that extends the neuronal surface on which synapses occur, as well as facilitates and stabilizes those contacts. Furthermore, dendritic spines dynamically change in shape and number in response to a variety of factors. Dendritic spine numbers are reduced in mental retardation, enhanced during development, sensory enrichment or physical exercise, or fluctuate during the reproductive cycle. Thus, for a given neuron type, it might be expected that dendritic spine number might achieve a dynamic optimum. Indeed, many studies of spine density of pyramidal neurons in sensory cortex indicate that an average of ~1.4 spines/micron occurs is present (Briner et al., 2010). Most such studies examined dendritic spines from primary sensory areas which are dominated by inputs from a single sensory modality. However, there are a large number of neural regions that receive inputs from more than one sensory modality and it is hypothesized that spine density should increase to accommodate these additional inputs. To test this hypothesis, the present experiments used Golgi-Cox stained layer 2-3 pyramidal neurons from ferret primary somatosensory (S1) and auditory (A1) cortical regions, as well as from the higher-level rostral posterior parietal (PPr) and lateral rostral suprasylvian (LRSS) multisensory areas. Spine densities in S1 (avg 1.309 ± 0.247 spines/micron) and A1 (avg 1.343 ± 0.273 spines/micron) were measured to be significantly greater (p<0.05, t-test) than those observed in multisensory regions PPr (avg 1.242 ± 0.205 spines/micron) or LRSS (avg 1.099 ± 0.217 spines/micron). These results also indicate that spine densities are greater in primary (S1, A1) than in higher-level (PPr, LRSS) sensory areas. The functional consequences of such unexpected findings are discussed in light of potential biophysical differences between unisensory and multisensory neurons.
|
165 |
Porovnání četností zranění ramene a páteře v 1. národní volejbalové lize mužů a žen. / Comparison in Frequency of Shoulder and Spine Injuries between 1 st National Volleyball Men's and Women's League PlayersVítová, Radka January 2014 (has links)
Name of the diploma thesis: Comparison in Frequency of Shoulder and Spine Injuries between 1st National Volleyball Men's and Women's League Players Goal of the diploma thesis: Goal of this thesis is to determine frequency of shoulder and spine injuries within men's category of professional volleyball. Thesis also surveys types of prevention and regeneration that players use, how long they warm up and how they compensate strain before training (match) and after training (match). At the end thesis compares men's results with women's that are based on survey from this thesis and from bachelor work (Vítová, 2012). Method: Required data was obtained by questionnaire in field. Acquired data was processed on the basis of perused Czech and foreign literature that is focused on injuries and prevention in sport. Results: Overview of frequency of shoulder and spine injuries within men's and women's volleyball. Key words: volleyball, injuries, shoulder, spine, prevention
|
166 |
Efekt fyzioterapeutických postupů po operaci krční páteře. / The effect of physiotherapeutic procedures on cervical spine surgery.Valášková, Veronika January 2017 (has links)
Author: Bc. Veronika Valášková Title of the work: The effect of physiotherapeutic procedures on cervical spine surgery. Aim: The aim of my thesis is to give an overview of the physiotherapy treatment after surgery of herniated cervical intervertebral disc. Methods: This thesis is written as a review of literature sources. The thesis consists of three parts, the first of which highlights the issue of kinesiology, biomechanics, stability of the cervical spine, pathophysiology of a prolapsed spinal disc and imaging issues involved in the discovery of a the actual prolapse. The second part deals with the various surgical techniques and associated complications. The final theoretical part looks into physiotherapy treatment after the operation. I examine the chronology of physiotherapy after the operation, and ascertain if there is a necessity to apply a neck brace after the surgery. It is important to answer the question of when it is possible to return to work and when the patient can return to their original physical activities. Results: The results of this thesis shows that postoperative care in individual departments vary and is inadequately described within available resources. Subsequent physiotherapy is dependent on the patient's condition before the operation, the operation itself, and its...
|
167 |
Detailed morphological study of layer 2 and layer 3 pyramidal neurons in the anterior cingulate cortex of the rhesus monkeyWang, Jingyi 22 January 2016 (has links)
The anterior cingulate cortex (ACC) can influence emotional and motivational states in primates by its dense connections with many neocortical and subcortical regions. Pyramidal neurons serve as the basic building blocks of these neocortical circuits, which have been extensively studied in other brain regions, but their morphological and electrophysiological properties in the primate ACC are not well understood. In this study, we used whole-cell patch clamp and high-resolution laser scanning confocal microscopy to reveal the general electrophysiological properties and detailed morphological features of layer 2 and 3 pyramidal neurons in ACC (area 24/32) of the rhesus monkey. Neurons from both layers had similar passive membrane properties and action potential properties. Morphologically, dendrites of layer 3 ACC neurons were more complex than those of layer 2 neurons, by having dendrites with longer total dendritic lengths, more branch points and dendritic segments, spanning larger convex hull volumes. This difference in total dendritic morphology was mainly due to the apical dendrites. In contrast, the basal dendrites displayed mostly similar features between the two groups of neurons. However, while apical dendrites extend to the same layer (layer 1), the basal dendrites of layer 3 extended into deeper layers than layer 2 because of the difference in soma-pia distance. Thus, basal dendrites of the two groups of neurons receive different laminar inputs. Analysis of spines showed that more spines were found in neurons of layer 3 apical dendritic arbors than layer 2 neurons. However, the apical spine densities were similar between neurons in the two layers. Thus, while higher spine number suggests that layer 3 neurons receive more excitatory input than layer 2 neurons, the similar spine density suggests similar spatial and temporal summation of these inputs. The combined effects of increased number of excitatory input and higher dendritic complexity in layer 3 than in layer 2 ACC neurons suggest the additional information received by layer 3 neurons, especially in the apical dendrites, might undergo more complex integration.
|
168 |
Influência do preparo do orifício piloto e da freqüencia de colocação do implante no seu torque de inserção e resistência ao arrancamento / Influence of the pilot hole preparation and screw frequency insertion of the implant on the insertion torque and pulling out resistanceRosa, Rodrigo César 04 September 2007 (has links)
O objetivo do estudo foi avaliar a influência do diâmetro do orifício piloto e a freqüência da colocação dos implantes no torque de inserção e na resistência ao arrancamento. Foram utilizados parafusos de 5, 6 e 7mm do sistema USS de fixação vertebral, os quais foram inseridos nos corpos de prova de madeira, poliuretana, polietileno e osso bovino. Para inserção dos implantes foram confeccionados com broca orifícios piloto com diâmetros menor, igual e maior que o diâmetro interno do parafuso. O torque de inserção dos parafusos avaliado nos corpos de prova de madeira foi mensurado por meio de torquímetro com capacidade de 5Nm, e nos demais corpos de prova foi utilizado torquímetro de 2Nm. Os ensaios mecânicos de arrancamento dos parafusos foram realizados utilizando máquina universal de ensaio Emic? e Software Tesc 3.13 para análise dos resultados, utilizando células de carga com capacidade de 2000 N e 20000 N, selecionadas de acordo com a resistência mecânica de cada corpo de prova, e com velocidade de aplicação de força de 2 mm/min. Os valores do torque de inserção dos parafusos de 5, 6 e 7mm de diâmetro externo, nos diferentes materiais, apresentaram maiores valores de torque na primeira inserção, com exceção dos corpos de prova de poliuretana com orifício piloto de 5,5mm. O diâmetro do orifício piloto em relação ao diâmetro interno do parafuso apresentou influência no torque de inserção dos implantes, nos diferentes corpos de prova, observando maior torque de inserção nos corpos de prova com orifício piloto menor que o diâmetro interno do parafuso e menor torque de inserção nos corpos de prova com diâmetro do orifício piloto maior que o diâmetro interno do parafuso. A força máxima de arrancamento nos parafusos de 5, 6 e 7mm de diâmetro externo, inseridos nos diferentes corpos de prova, apresentaram maiores valores na primeira inserção nos diferentes diâmetros de orifício piloto. O diâmetro do orifício piloto em relação ao diâmetro interno do parafuso apresentou influência na força máxima de arrancamento dos implantes, nos diferentes corpos de prova, observando maior força de arrancamento nos corpos de prova com orifício piloto menor que o diâmetro interno do parafuso e menor força de arrancamento nos corpos de prova com diâmetro do orifício piloto maior que o diâmetro interno do parafuso. Podemos concluir que a freqüência de colocação dos implantes influencia na qualidade da ancoragem. A realização de menor freqüência de colocação dos implantes proporciona uma melhor fixação. A perfuração do orifício piloto com instrumental de menor diâmetro, em relação ao diâmetro interno do parafuso, tende a apresentar melhor fixação do parafuso que a perfuração com diâmetro maior. / The aim of the study was to evaluate the influence of the diameter of the pilot hole and the frequency of screw placement on pullout out resistance and insertion torque of the pedicle screw. Pedicle screws of 5, 6 and 7mm of the USS system for vertebral fixation were inserted into wood, polyurethane, polyethylene and bovine bone. The pilot hole for screw insertion was drilled with small, equal and wider than the internal diameter of the screw. The insertion torque was measured in the wood test bodies used a torquímetro with capacity of 5Nm, and other test bodies was used a torquimetro of 2Nm. Mechanical pullout assays were performed using a universal testing machine rehearsals of screws pullout were accomplished using universal machine Emic® and Software Tesc 3.13 for analysis of the results. Load cells were using with capacity of 2000 N and 20000 N, selected in agreement with the mechanical resistance of each test bodies. A constant displacement rate of 2mm/min was applied until failure. The values of the insertion torque of the screws of 5, 6 and 7mm of external diameter, in the different materials, they presented highest insertion torque in the first insert, in the different materials, except for the polyurethane test bodies with pilot hole of 5,5mm. The diameter of the pilot hole in relation to the internal diameter of the screw exerts an influence in the torque of insert of the implants. We observed highest insert torque in the test bodies with smaller pilot hole than the internal diameter of the screw and smaller insert torque in the proof bodies with diameter of the wider pilot hole than the internal diameter of the screw. The pullout resistance of the screws of 5, 6 and 7mm of external diameter performed highest values in the first screw insert, in the different diameters of pilot hole and test bodies. The diameter of the pilot hole in relation to the internal diameter of the screw exerts an influence in the pullout resistance of the implants. The highest pullout resistance was observed in the test bodies with smaller pilot hole than the internal diameter of the screw. The smaller pullout resistance was observed in the test bodies with diameter of the larger pilot hole than the internal diameter of the screw. We can conclude that the frequency of placement of the implants influences in the quality of the anchorage. The accomplishment of smaller frequency of placement of the implants provides a better fixation. The perforation of the pilot hole with instrumental of smaller diameter, in relation to the internal diameter of the screw, tends to present better fixation of the screw than the perforation with larger diameter.
|
169 |
"Validação de testes de flexibilidade da coluna lombar" / VALIDATION OF LUMBAR SPINE FLEXIBILITY TESTSAchour Júnior, Abdallah 22 March 2006 (has links)
Esta pesquisa teve como principal objetivo, validar o teste de flexibilidade da coluna lombar (Testprop), utilizando-se da radiografia como teste critério e o teste flexibilidade da coluna lombar de ADRICHEM e KORST (1973) para o sexo feminino e masculino. Participaram 19 mulheres (média de idade= 23,2 anos e desvio padrão= 1,3) e 18 homens (média de idade= 22,3 anos e desvio padrão= 1,4), universitários, saudáveis e ativos do Curso de Educação Física e Ciências do Esporte da Universidade Estadual de Londrina - PR. Inicialmente, verificou-se a fidedignidade e objetividade dos testes de flexibilidade da coluna lombar (Testprop e Testeips). O coeficiente de correlação intraclasse mostrou que o teste de flexibilidade Testprop apresenta fidedignidade elevada para o sexo feminino (R= 0,86) e elevada para o sexo masculino (R=0,85), e demonstrou haver objetividade moderada (R= 0,73) para o sexo feminino e elevada (R= 0,96) para o sexo masculino. Quanto ao teste de flexibilidade Testeips, a fidedignidade foi elevada (R= 0,85) e (R= 0,86) para o sexo feminino e masculino, respectivamente. A objetividade do teste de flexibilidade Testeips foi moderada (R= 0,62) para o sexo feminino e elevada para o sexo masculino (R= 0,91). Em relação à validade, o coeficiente de correlação de Pearson mostrou correlação baixa para o teste de flexibilidade Testprop (r= 0,11) para o sexo feminino e correlação moderada (r= 0,52) para o sexo masculino. No que diz respeito ao teste de flexibilidade Testeips, o coeficiente de correlação de Pearson foi baixo para o sexo feminino (r= 0,24) e moderado para o sexo masculino (r= 0,50). Concluiu-se que os testes de flexibilidade da coluna lombar Testprop e Testeips foram fidedignos e objetivos, mas não foram considerados válidos. / The main goal was to validate the flexibility test for the lumbar spine (Testprop), using x-ray as a criteria and the flexibility test of the lumbar spine designed by ADRICHEM and KORST (1973) for females and males, 19 women participated (mean age= 23,2 years old; standard deviation= 1,3 year old) and 18 men (mean= 22,3 year old and standard deviation = 1,4) healthy and active students from the Physical Education and Sport Science Course at the Universidade Estadual de Londrina-PR. Initially, it was verified reliability and objectivity (Testprop and Testeips) the lumbar spine flexibility. The intraclass correlation coefficient showed that the reliability of test of flexibility Testprop was high for woman (R= 0.86) and high for men (R= 0.85), there was a moderate objectivity (R= 0.73) for women and high (R= 0.96) for men. Concerning the flexibility test Testeips, the reliability was high (R= 0.85) and (R= 0.86) for woman and men, respectively. The objectivity for the flexibility test Testeips was moderate (R= 0.62) for women and high for men (R= 0.91). Concerning the validity, Pearson correlation coeficient demonstrated a low correlation for the flexibility test Testprop (r= 0.11) for women and moderate for men (r= 0.52). About the flexibility test, Testeips, Pearson correlation coefficient was low for woman (r= 0.24) and moderate for men (r= 0.50). It was concluded that the flexibility tests of the lumbar spine Testprop and Testeips were reliable and objective, but they were not considered valid.
|
170 |
Aspectos metodológicos para a determinação de cargas internas na coluna vertebral. / Methodological aspects to determining the internal loads on the human column.Santa Maria, Adriana Simone Lopes 31 August 2001 (has links)
A elevação de uma carga leva ao surgimento de uma força de contato a região lombar (L5-S1) que pode atingir algumas vezes o valor do próprio peso do indivíduo, valor este que depende da carga elevada. A análise das forças (musculares, peso, carga), considerando a coluna como uma haste rígida, cuja extensão é feita unicamente pelo eretor espinhal, representa uma aproximação muito pobre para o sistema, uma vez que as diversas forças musculares envolvidas não são adequadamente analisadas e o movimento de retificação da coluna vertebral é desprezado. O objetivo do presente trabalho foi o desenvolvimento de um modelo biomecânico simplificado em 2 dimesões, para a avaliação das forças atuantes durante atividades de levantamento impróprio de carga e o movimento de flexão/extensão a coluna lombar. A coluna vertebral foi modelada como um conjunto de três segmentos retilíneos rígidos articulados e entre si. Utiliza do o método da dinâmica inversa, aplicado a um modelo de segmentos articulados simplificado, foram estimadas as forças musculares médias e a força de contato articular na articulação vertebral L5-S1 como função dos â ângulos de inserção da musculatura extensora da coluna. Para a construção do modelo foram identificados: musculatura principal, dados antropométricos, ângulos de inserção musculares, modelo antropométrico e registro da imagem do levantamento de peso. O modelo matemático forneceu um sistema de equações que avaliam as forças que atuam na coluna vertebral durante o movimento de extensão, em função de dados a atômicos. / Load lifting yields a contact force in the lumbar region (L5-S1) that can sometimes reach the value of the body weight, depending upon the elevated load. Force analyses (muscular, weight, load), the spine being consided as a rigid shank, with extension beimg done only by the erector spine musculature, represent a poor approximation, since the several muscular forces involved are not adequately analysed and the rectification movement of the spine is not taken into account. The purpose of this study was to develop a simplified two dimensional biomechanical model in order to evaluate the forces during activities of improper load bearing and the movement of flexion/extension in the lumbar spine. The spine was assumed as a linear rigid array of articulate segments. Using inverse dynamics applied to a simplified link segment model,the average muscular forces and bone-to-bone contact force in the L5-S1 vertebral joint were evaluated as a function of the back extension muscles insertion angles. For the model construction the main musculature, the anthropometric data, and model the muscle insertion angles, and the image acquisition register of the weight loading movement were identified. The mathematical model yielded a system of equations that evaluates the acting forces on the spine during the extension movement, as a function of the a atomical data.
|
Page generated in 0.0611 seconds