Made available in DSpace on 2014-06-11T19:30:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-05-04Bitstream added on 2014-06-13T19:00:54Z : No. of bitstreams: 1 dascal_jb_dr_rcla.pdf: 761965 bytes, checksum: da9f940aa470e3ce04d2c7f21b70f688 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O número de quedas durante o envelhecimento é alto e as consequencias para o indivíduo podem ser drásticas. O entendimento do funcionamento do sistema de controle postural é importante na medida que pode minimizar a quantidade de quedas nesta fase da vida e com isto melhorar a qualidade de vida destas pessoas. Foram realizados dois estudos com o objetivo de investigar os efeitos do envelhecimento sobre o controle postural com o uso de uma ferramenta não-rígida, denominada de sistema âncora, em contextos que restringem a informação visual. O primeiro estudo investigou a estabilidade postural de 15 adultos jovens (média de idade de 20.20 anos ± 1.61) e 15 idosos (média de idade de 68.13 anos ± 6.09) em uma tarefa postural com restrição da base de suporte (posição semi-tandem) sem restrição da informação visual (fixando o olhar a um ponto fixo), e na ausência da informação visual, com utilização do sistema âncora (125 g) e uma condição controle. As medidas do centro de pressão (Cop) foram obtidas através da plataforma de força e as variáveis dispersão, amplitude e velocidade da oscilação na direção médio-lateral e antero-posterior foram analisadas. Os resultados mostraram que o grupo de idosos apresentou maior oscilação corporal que o grupo de adultos jovens, nas duas condições visuais investigadas; que a ausência da informação visual provocou maior instabilidade postural para ambos os grupos e que o sistema âncora foi útil para estabilizar a postura dos dois grupos estudados, com uma diferença entre os grupos: para o grupo de adultos jovens a efetividade do sistema âncora foi maior para as condições em que a informação visual estava ausente e para o grupo de idosos o uso do sistema âncora foi mais efetivo nas condições em que a informação visual estava presente. A partir destes resultados, concluímos que o sistema âncora... / There is a lot of falls during aging and the results for the person can be drastic. The understanding of the postural control system is important because it can reduce the amount of falls during this phase and it can improve the quality of life of old adults. Two studies were designed to investigate the effects of the aging on postural control using a non-rigid tool, called anchor system. Two different contexts were presented: with and without visual restriction (blindfolding and visual illusion). The first study investigated the postural stability of 15 old adults (mean age of 20.20 years ± 1.61) and 15 young adults (mean age 68.13 years ± 6.09) in a postural task with the restriction of the base of support (semi-tandem position) while looking at a fixed point, and when visual information was absent. These conditions included the use of the anchor system (125 g) and a baseline condition. The center of pressure (Cop) measures was obtained from the signal of a force plate. Variables included: dispersion, amplitude and velocity of sway in medial-lateral and anterior-posterior direction. The results showed that the older adults swayed more than young adults in both visual conditions. For the conditions with no visual information both groups showed more instability. The anchor system helped to stabilize the posture for both groups, with one difference between the groups: for the young adults the effectiveness of using the anchor system was better for conditions where the visual information was absent; for older adults, the usefulness of the anchor system was superior in conditions where the visual information was present Based on these results we concluded that the anchor system can be used for stabilization of the posture for older and young adults. The second study investigated the postural stability of 15 old adults and 15 young adults in the same postural task... (Complete abstract click electronic access below)

The ability to respond rapidly with spatial precision is required in a number of facets of everyday life, whether catching a falling object, reacting to other drivers on a busy freeway or recovering one’s balance following an unexpected perturbation. The sophisticated central nervous system (CNS) control of these reactions is often overlooked until the speed of such reactions becomes delayed, either due to ageing or brain injury, wherein the individual becomes at risk of injury. Surprisingly, little is known regarding the control of these ‘temporally urgent’ movements. Therefore, the primary objectives of this dissertation were to develop an understanding of the control of these movements by exploring the factors that may be involved in the generation of temporally urgent movements in the healthy CNS, locating the areas within the CNS that such modulation occurs and identifying the relative weighted importance of those modulators based on the initial conditions of stimulus delivery. Specific characteristics of stimulus properties, such as intensity and modality were particularly influential in the latency of motor reactions and physiological electrodermal skin responses fluctuated in accordance with input stimulus parameters. Importantly, outcomes from this dissertation identified that rapid reactions likely utilize a CNS network that includes higher cortical regions such as somatosensory cortex and primary motor cortex, which may be modulated by physiological arousal, rather than the solitary involvement of subcortical structures. The findings from this dissertation have important implications for individuals with disordered speed of processing and indicate the potential modifiability of factors that influence reaction time.

The aim of the work was to determine if the use of physical therapy helps improve balance and gait ability of patients ill with multiple sclerosis. Twenty three patients ill with multiple sclerosis, who received a 1-hour physical therapy treatment at their home 3 times a week for one month, took part in the investigation. Balance of patients ill with multiple sclerosis was evaluated by the Berg balance scale and the gait index. The investigation has shown that before the use of physical therapy the balance and gate abilities of most investigated patients were poor . After the course of physical therapy by carrying out the same tests the balance and gait improvement was observed. Before physical therapy the balance total average of points for all tasks was 2,82±0,83 points, while after physical therapy it was 3,25±0,83 points (p<0,05). The sum of points of fulfilling all the tasks after physical therapy was larger by 10 points (p<0.05). In the evaluation of gait before physical therapy the average was 1,54±0,62 points, and after physical therapy it was 2,07±0,62 points (p<0,05). The sum of points of fulfilling all the tasks after physical therapy was larger by 12,2 points (p<0.05). After the course of physical therapy the number of patients who could keep their balance without risk of falling increased by 26,1%, and the number of patients whose gait abilities improved without risk of falling increased by 43,5%. We can draw the conclusion that physical therapy distinctly... [to full text]

The ability to respond rapidly with spatial precision is required in a number of facets of everyday life, whether catching a falling object, reacting to other drivers on a busy freeway or recovering one’s balance following an unexpected perturbation. The sophisticated central nervous system (CNS) control of these reactions is often overlooked until the speed of such reactions becomes delayed, either due to ageing or brain injury, wherein the individual becomes at risk of injury. Surprisingly, little is known regarding the control of these ‘temporally urgent’ movements. Therefore, the primary objectives of this dissertation were to develop an understanding of the control of these movements by exploring the factors that may be involved in the generation of temporally urgent movements in the healthy CNS, locating the areas within the CNS that such modulation occurs and identifying the relative weighted importance of those modulators based on the initial conditions of stimulus delivery. Specific characteristics of stimulus properties, such as intensity and modality were particularly influential in the latency of motor reactions and physiological electrodermal skin responses fluctuated in accordance with input stimulus parameters. Importantly, outcomes from this dissertation identified that rapid reactions likely utilize a CNS network that includes higher cortical regions such as somatosensory cortex and primary motor cortex, which may be modulated by physiological arousal, rather than the solitary involvement of subcortical structures. The findings from this dissertation have important implications for individuals with disordered speed of processing and indicate the potential modifiability of factors that influence reaction time.

The aim of the work was to determine if the use of physical therapy helps improve balance and gait ability of patients ill with multiple sclerosis. Twenty three patients ill with multiple sclerosis, who received a 1-hour physical therapy treatment at their home 3 times a week for one month, took part in the investigation. Balance of patients ill with multiple sclerosis was evaluated by the Berg balance scale and the gait index. The investigation has shown that before the use of physical therapy the balance and gate abilities of most investigated patients were poor . After the course of physical therapy by carrying out the same tests the balance and gait improvement was observed. Before physical therapy the balance total average of points for all tasks was 2,82±0,83 points, while after physical therapy it was 3,25±0,83 points (p<0,05). The sum of points of fulfilling all the tasks after physical therapy was larger by 10 points (p<0.05). In the evaluation of gait before physical therapy the average was 1,54±0,62 points, and after physical therapy it was 2,07±0,62 points (p<0,05). The sum of points of fulfilling all the tasks after physical therapy was larger by 12,2 points (p<0.05). After the course of physical therapy the number of patients who could keep their balance without risk of falling increased by 26,1%, and the number of patients whose gait abilities improved without risk of falling increased by 43,5%. We can draw the conclusion that physical therapy distinctly... [to full text]

Interactions between the neural and musculoskeletal systems are a prerequisite for the production of robust movement. In spite of this, the neural control and musculoskeletal structure underlying biological movements are typically studied independently, with little attention paid to how changes in one may affect the other. Understanding these interactions may be critical to improving current rehabilitation technologies and therapy methods. As an example, balance disorders are multifactorial in nature and identifying whether biomechanical or neural changes are the source of instability remains an unanswered question. I have used a combined experimental and modeling approach to understand neural and biomechanical interactions governing human balance control. I developed a simple four-bar linkage model with delayed feedback to investigate frontal-plane standing balance. Using methods from time-delay systems I present evidence from this model that biomechanical structure is important for behavioral function and show that neural control and biomechanical structure co-vary for stable human balance. Predictions from the model were tested experimentally to dissociate the effects of inertia and postural configuration on balance. In addition, I applied robust control methods to solve the difficult problem of comparing the relative performance between neuromechanical systems that differ in parameter values and predicted a common mechanism to explain changes in neural control across biomechanical contexts. In the future, the analytical tools and simulation methods I have developed can be generalized to investigate changes in neuromechanical interactions of various deficits in biomechanics (ACL rupture, amputation) and neural control (Parkinson's disease, stroke). Furthermore, this approach can be used to explain how neural control and biomechanical structure relate to the diversity of animal form and function, as well as suggest biomimetic control policies for robotics.

The rollator is a mobility aid commonly used to facilitate balance and mobility for individuals with cardiorespiratory, musculoskeletal, or neurological deficits. Despite its popularity, there are also reports of adverse effects related to walker use linked to increased fall risks. Studies examining the effectiveness and consequences of rollator use have employed standard laboratory-based measurement methods that rely on performing specific tasks within a short time period and under controlled conditions, potentially limiting generalization to mobility in the everyday context. An instrumented rolling walker (iWalker) was developed as an ambulatory measurement tool applicable to the assessment of balance outside of the lab or clinic for assistive device users. The iWalker autonomously collects measurements of the upper and lower limb behaviour related to balance, walker kinematics, and video of the immediate spatial environment. The design and development of the iWalker is first described, followed by two studies characterizing the involvement of the upper limbs for balance in standing and walking that served to address gaps in the literature and evaluate the utility of the upper limb measures. Overall, the upper limbs can become the primary effectors of balancing forces when lower limb capabilities are compromised. When lower limb involvement was experimentally constrained, the upper limbs became the primary effectors of balance control in healthy, young adults. In older adults, individuals demonstrating the highest upper limb usage during walking were associated with the largest reduction in frontal plane stepping parameters (i.e., step width). A third study evaluated the applicability of the iWalker to assess everyday mobility in a series of in-patients recovering from neurological injury (i.e., stroke, traumatic brain injury). Patients demonstrated significantly different upper limb balancing behaviour in everyday situations compared to in-laboratory assessments. Furthermore, the iWalker captured behaviours that may be precursors to falling, such as collisions, stumbling and lifting the assistive device. The implications of these studies on assessing the effectiveness of rollators and feasibility of using the iWalker in follow-up efforts are discussed.

Thesis (M.S.)--Miami University, Dept. of Physical Education, Health, and Sport Studies, 2005. / Title from first page of PDF document. Document formatted into pages; contains [1], iv, 44 p. : ill. Includes bibliographical references (p. 23-27).

Made available in DSpace on 2014-06-11T19:22:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-15Bitstream added on 2014-06-13T19:28:14Z : No. of bitstreams: 1 nozabieli_ajl_me_prud.pdf: 389297 bytes, checksum: 18d283320999ea56627c9e2743d72159 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O estudo teve por objetivo avaliar as pressões e áreas de superfícies plantares e os componentes vásculo-sensório-motores dos pés de portadores de neuropatia diabética. Sessenta e oito indivíduos divididos em dois grupos: 28 no grupo neuropata e 40 no grupo controle, participaram do estudo. Os voluntários foram submetidos às avaliações da circulação e perfusão periférica de membros inferiores, por meio do índice tornozelo/braço e oximetria; sensibilidade somatossensitiva, pela estesiometria; força muscular do tornozelo, por dinamômetro digital portátil; e pressões e superfícies plantares com um baropodometro eletrônico. Os grupos foram comparados por meio dos testes Mann-Withney e análises de variâncias (ANOVA e MANOVA) (p<0,05). A sensibilidade tátil, o índice tornozelo/braço e a força muscular de dorsiflexores e plantiflexores de tornozelo estiveram diminuídas no grupo neuropata em relação aos controles. Nos picos de pressões plantares não foram verificadas diferenças entre os grupos, mas ocorreu diferença nos locais onde essas pressões foram impostas. Na condição estática, a área de superfície plantar foi maior no grupo neuropata, quando comparado ao controle... / The objective of this study was to analyze the postural control, using baropodometry, in patients with diabetic neuropathic and relate with loss in the sensorimotor system. Twenty-eight healthy subjects and 25 patients with diabetic neuropathic were evaluated with baropodometry in two conditions: static (for measure the center of pressure displacement) and dynamics (for measure the stance phase of gait cycle – total period of support, double support and single support). The tactile sensitivity of the feet was measured with a Semmes-Weinstein pressure esthesiometer and the isometric muscle strength of ankle was measured with dinamometry. The MANOVA and ANOVA indicated lower performance in tactile and force muscle in diabetic neuropathy. In the dynamic condition the diabetic neuropathy group showed more time in the gait parameters. With this study, by regression analysis, we can say that the differences of balance in the neuropathy diabetic gait may result from decreased of sensitivity tactile and strength

Made available in DSpace on 2014-06-11T19:22:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-26Bitstream added on 2014-06-13T19:49:10Z : No. of bitstreams: 1 lucena_cs_me_rcla.pdf: 305179 bytes, checksum: 6f2b882000a95a43bddf02b90e85bf16 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O controle postural está relacionado com os ajustes corporais necessários à manutenção ou à busca da postura desejável, de acordo com a meta da tarefa. Mesmo um comportamento cotidiano como permanecer em pé, pode ser considerado uma tarefa complexa que envolve um estreito relacionamento entre informação sensorial e atividade motora. Barela (2000) afirma que as forças atuantes nos segmentos corporais não são constantes, pois, mesmo que a pessoa se mantenha o mais estável possível, o corpo nunca está totalmente imóvel. Por isso, a postura em pé é chamada de “quase-estável”. Algumas populações têm maior predisposição a apresentar problemas de ordem postural, como por exemplo, obesos, idosos ou pessoas com deficiência intelectual – DI. As pessoas obesas ou com sobrepeso, por apresentarem maior acúmulo de gordura na região abdominal, estão mais propensas à perda de equilíbrio ou eventuais quedas, pois o centro de massa está deslocado para frente. Uma população bastante exposta à obesidade é aquela com deficiência intelectual, quer seja por característica genética, por maus hábitos alimentares ou estilo de vida sedentário. A fim de verificar a associação da obesidade com a deficiência intelectual quanto ao controle postural em tarefa do tipo estática em pé, foram recrutados 40 participantes. A tarefa consistiu em permanecer em pé sobre uma plataforma de força e foram realizadas sete tentativas: uma chamada de controle na qual os pés permaneciam paralelos e os olhos abertos, três tentativas com os pés em posição semi-tandem – ST – e os olhos abertos e outras três tentativas com os pés em posição ST e os olhos fechados. As variáveis dependentes analisadas foram: amplitude média de oscilação e amplitude média da velocidade de oscilação, em ambas... / Postural control is related to the adjustments needed to maintain body or the search of desirable posture, according to the goal of the task. Even an everyday behavior such as standing, can be considered a complex task that involves a close relationship between sensory information and motor activity. According to Barela (2000) the forces acting on the body segments are not constant, so even if the person remains as stable as possible, the body is never completely still. Therefore, the standing posture is called quasi-static. Some populations are more likely to present postural problems, for example, obese, elderly or people with intellectual disabilities - ID. People who are obese or overweight, had higher accumulation of abdominal fat are more prone to loss of balance or falls, as the center of mass is moved forward. A population exposed for the obese is that with intellectual disabilities, whether by genetic feature, poor eating habits or sedentary lifestyle. In order to verify the association of obesity with intellectual disabilities on the postural control tasktype static standing, 40 participants were recruited. The task was to stand on a force platform and seven attempts were made: one call control in which the feet parallel and the eyes remained open, three attempts with their feet in a semi-tandem - ST - and open eyes and three more attempts with his feet in position ST and eyes closed. The dependent variables were analyzed: amplitude of oscillation and amplitude of the oscillation velocity in both ML and AP directions. The results showed that all participants had changed postural control in changing the position of the feet as in the occlusion of vision. The groups non-obese without ID and obese with ID were different for both variables, supporting the hypothesis that obesity affects postural control and... (Complete abstract click electronic access below)