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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.
171

A Non Invasive Complex Representation of Muscle: A Description through BOLD Fractal Dimension, Phase Space, and Concurrent EMG Metrics / Understanding and Describing Muscle Complexity

McGillivray, Joshua 11 1900 (has links)
An investigation into the complex function of muscle using non-invasive imaging and novel analytical approaches. / The human body is inherently complex as seen through the structural organization of muscle in terms of its contractile subunit organization and scaling, innervation patterns, and vascular organization. However, the functional complexity of muscle such as its state of oxygenation, metabolism or blood-flow has been less well explored. Thus in an effort to improve our understanding of muscle, blood oxygenation level dependent (BOLD) magnetic resonance imaging of the lower leg, at rest and during a variety of weighted plantar-flexion paradigms, at 40% maximal voluntary contraction, was employed. Prior to experimentation, on 11 healthy subjects, an ergometer and electromyogram (EMG), suitable for use within the MRI, were constructed to allow for concurrent exercise and image acquisition. After collecting muscle BOLD data, four novel techniques were using to describe muscle function. The first technique used the fractal dimension, a measure of complexity, conveying the rate of variation of muscle blood flow at rest. This technique was able to determine differences between the muscles of lower leg, which have varying distributions of muscle fibre types based on function. The second exploratory technique was the use of the phase space, which provides insight into state/state-transitions of a system over time. The phase space representation of the BOLD signal provided novel insight into the muscle activation state. It demonstrated that muscle has more than the two blood flow states of reduced levels at rest and increased levels when exercising. The third technique involved using a signal saturation (SAT) region, proximal to the imaging region, to mitigate the arterial in-flow effects to more accurately represent muscle activation. By observing the correlation between the ideal reference and recorded signal, the acquisition with the arterial suppression improved the assessment of what regions in the muscle were active in the range borderline activation, which has the highest uncertainty. The final outlook on muscle behaviour involved using measures of fatigue from the collected EMG data to develop novel metrics of fatigue based on the BOLD signal. Concurrent BOLD and EMG of the anterior compartment of the lower leg during a plantar-flexion block design, demonstrated that the change in blood-flow between rest and contracted states is an excellent indicator of muscle fatigue. The primary outlook of this thesis is to provide a unique data collection and analytic framework to describe muscle behaviour, which was achieved using non-invasive measures with a complex outlook. / Thesis / Master of Applied Science (MASc) / The human body is complex, and an incredible amount of research has been done to better understand it. Specifically, muscle is built and works in a complex way to allow us to move and perform everyday tasks. There are many diseases that affect how a muscle works, which is why there is a need to describe muscle performance when it is healthy and unhealthy. In this research, muscle behaviour is explored by taking pictures of the leg. From these pictures the blood flow in the calf and shin was measured both when staying still and when performing exercise. Four new techniques were created to describe the blood flow in the leg. The first technique measured how complex the muscle activity is, while staying still. If blood-flow changes a lot in a short amount of time, it is complex. This showed that the different components of muscle, either used for stamina or power, receive blood differently. The second technique used a different way of looking at the muscle to show that there are many different rates and amounts of blood-flow in the muscle. It revealed that muscle has more than the two blood flow options of 1) the normal level when resting and 2) the increased level when exercising. The third technique involved using an image filter to get a clean image of the muscle without the blood vessels affecting or misrepresenting the image. It was able to show what muscle regions were involved in exercise more accurately than before. The final technique involved measuring muscle electricity and blood flow at the same time, to find out when the muscle was exhausted. It demonstrated that muscle, when exhausted, showed larger changes in blood flow when going from resting to exercising. Overall, this research described how muscle performs in healthy individuals using new techniques. These techniques can now be used to compare healthy muscle to damaged/diseased muscle to determine how the muscle is recovering or to diagnose muscular disease.
172

Developing Techniques in Electromyography to Facilitate Translation to Healthcare

Toepp, Stephen January 2024 (has links)
Voluntary or involuntary muscle activation can be captured by surface electromyography (EMG), which detects muscle action potentials via sensors on the surface of the skin. The technique has been prominent in the study of physiological underpinnings of movement for over 80 years and continues to be an essential tool in scientific research. Its research topic applications include motor disorders caused by stroke, spinal cord injury, cerebral palsy, multiple sclerosis, and many others. Benefits of integrating surface EMG into healthcare have been extensively argued and supported by scientific research, but adoption in clinical settings has been frustratingly slow. The overall goal of this thesis is to advance the clinical adoption of surface EMG by developing techniques that emphasize accessibility and the needs of the end-user (i.e., clinicians). In the first chapter, this dissertation leverages theoretical and empirical literature concerning influencers of adoption, and published clinician perspectives, to determine an effective translation strategy. Developing enhanced therapeutic surface EMG techniques and complementary assessments techniques were identified as key strategic goals. In Chapter 2, I develop a new classification-based surface EMG biofeedback system designed to emphasize tailorability, flexibility, and accessibility. The system performed well during a single session in healthy participants and one individual with multiple sclerosis. In Chapter 3, tailored interventions were implemented across multiple sessions in a group of multiple sclerosis patients with severe motor impairment. Implementation was found to be feasible, and the classification record emerged as an efficient and intuitive means to monitor and assess characteristics of a training session. In Chapter 4, I develop and test an easy-to-replicate surface EMG acquisition approach, and an analysis method using simple cursor placements. The analysis method was reliable between raters and sessions in healthy male and female participants. Overall, this thesis contributes to the translation of surface EMG methods into clinical practice. / Thesis / Doctor of Science (PhD) / Surface electromyography (EMG) is the recording of electrical potentials within the muscle that drive muscle contraction, and ultimately movement. There are many surface EMG techniques that provide insightful glimpses of the processes governing movement, and they have long been used to study movement impairments caused by traumatic injuries, neurodevelopmental disorders, and neurodegenerative diseases. Use of surface EMG to inform treatment decisions and optimize therapeutic interventions may significantly improve health outcomes. However, clinicians across the various healthcare fields have been slow to take advantage of surface EMG, and it remains underutilized despite significant efforts promote its use. The goal of this thesis is to develop accessible surface EMG techniques that can be applied in therapy and assessment scenarios. Ultimately, beyond the thesis, this work is intended to advance the clinical adoption of surface EMG so that its benefits may be accessed by a greater portion of practicing clinicians and their patients.
173

Behavioural and Electrophysiological Studies of Sleep and Animal Hypnosis

Harper, Ronald 06 1900 (has links)
EEG, EMG, and single cell activity were examined under states of animal hypnosis, sleep, and wakefulness. Rabbits and chickens were repetitively hypnotized to determine whether animal hypnosis was caused by a fear reaction. Differential susceptibility of chickens and rabbits to animal hypnosis suggests that more than a "paralysis of terror" is involved in causing this state. There was a difference in theta frequency in records from moving and still animals, and a 13-18 Hz component appeared on many records during synchronized and desynchronized sleep. A large number of cells fired with respect to certain EEG conditions rather than to a behavioural state. EEG and single cell activity obtained during early hypnosis were very similar to those appearing in an animal that was sitting alert. / Thesis / Doctor of Philosophy (PhD)
174

Ker-EGI : «Kerpape-Rennes- EMG-based-Gait-Index» : définition d’un index de quantification de la marche pathologique par électromyographie / Ker-EGI : «Kerpape-Rennes-EMG-based-Gait-Index» : a new index of pathological gait quantification based on electromyography

Bervet, Kristell 18 September 2012 (has links)
La marche est le mode de locomotion naturel de l’homme. Malgré les très nombreuses études s’y étant intéressé, cela reste un mouvement complexe. Ceci est d’autant plus vrai lorsqu’une pathologie vient le perturber. Dans le cadre clinique, le recueil de données réalisé est appelé l’Analyse Quantifiée de la Marche (AQM). Elle s’adresse, notamment, à des patients souffrant de troubles de la marche issus de pathologies affectant le système nerveux central. La quantité dedonnées pouvant être extraite d’une AQM étant très importante, des index ont été définis et validés. Le Gillette Gait Index (GGI), le Gait Deviation Index (GDI) et l’Edinburgh Visual Gait Score (EVGS) sont parmi les plus utilisés. Leurs limites principales sont qu’ils ont été définis que pour la prise en charge des enfants paralysés cérébraux et qu’ils sont basés presque exclusivement sur la cinématique. Les modalités de calcul de ces index n’étant pas spécifiques de la pédiatrie, dans un premier temps, nous avons voulu voir comment ceux-ci se comportaient chez l’adulte. Nous avons ainsi, par la démonstration de l’applicabilité du GGI, du GDI et de l’EVGS, validé le principe de l’AQM chez l’adulte. Cependant, de façon courante, l’AQM comprend dans son protocole un enregistrement électromyographique (EMG) qui ne fait que très rarement l’objet d’une réelle quantification à la marche. Nous avons donc, dans un second temps, défini un nouvel index dequantification de la marche pathologique basé sur l’EMG : le Ker-EGI. Cet index reprend la philosophie et le modèle mathématique du GDI. Nous avons validé le Ker-EGI chez l’adulte en le corrélant avec le GGI, le GDI et l’EVGS. Ce nouvel index va permettre de réaliser, à moindre coût, un meilleur suivi au quotidien des patients. Il est plus accessible en routine clinique et pourra être associé à l’EVGS pour donner un tableau clinique complet du patient (regards neuromoteur etcinématique) / Walking is the natural way of locomotion for human. Nevertheless, despite numerous studies, it remains a complex movement. This is all the more real when a pathology disturbs it. Data collection made on patients is called Clinical Gait Analysis (CGA). This is dedicated, in particular, to patients with a central nervous system disorder. As data outcoming from the CGA could be very heavy, indices have been defined and validated. Among the most used are the Gillette Gait Index(GGI), the Gait Deviation Index (GDI) and the Edinburgh Visual Gait Score (EVGS). Their main limitations are that they have only been defined for children with cerebral palsy and they are based quite solely one kinematics. As the methods to compute these indices are not child-specific, we have first evaluated how they could also be used in adults. So, demonstrating the applicability of the GGI, the GDI and the EVGS, we have validated the principle of CGA in adults. Usually, the CGA’s protocol includes electromyographic measures (EMG), but rarely these data are really quantified. That is why, secondly, we have defined a new index of gait quantification based on EMG: the Ker-EGI. This index uses the philosophy and the mathematical model of the GDI. We have validated the Ker-EGI in adults correlating it with the GGI, the GDI and the EVGS. This new index more accessible in clinical routine allows to perform, for a lower cost, a better patient’s care in everyday life. Furthermore, if the Ker-EGI is associated with the EVGS, we have a more complete clinical picture with a neuro-motor and kinematic view of the patient
175

Možnosti využití Aquaterapie pro stabilizaci ramenního pletence / Possibility of using Aqua Therapy for shoulder stabilization

Sulková, Ivana January 2011 (has links)
Title: Possibility of using Aqua Therapy for shoulder stabilization The aim of this thesis was to refer to possibility of using Aqua Therapy in Physiotherapy, especially to possibility of using Aqua Therapy for shoulder girdle stabilization. The thesis is supplemented by pilot study, witch compare activity of scapula stabilizing muscles dutiny movement on land with Thera-Band and in water with different equipment. Activity of selected muscles was documented and compared using surfaře electromyography. The results indicate flatter curve of selected muscles activation and their ko-contraction during movement in water condition. The results also refers to no significant differences in muscle activation in water and on dry land. Water exercise demonstrated in this study can by considered to be effective for improvement of scapular stabilization. Keywords: Aqua Therapy, water exercise, electromyografy, water EMG, scapular stabilization
176

EMG analýza vlivu vodního prostředí na rehabilitaci u pacientů s Parkinsonovou nemocí / An electromyographical analysis of the influence of water environment on the rehabilitation of patients with Parkinson's disease

Kotalíková, Kateřina January 2013 (has links)
Title: An electromyographical analysis of the influence of water environment on the rehabilitation of patients with Parkinson's disease Aims: The main aim of this Master's thesis was to compare electrical activity of selected muscles of patients with Parkinson's disease via electromyography during gate aground and in water environment. Furhter aim was to determine co-contraction level of leg muscles of patients with Parkinson's disease during gait aground and in water environment. Methods: This thesis is a case study, which was conducted on five probands, two of which were men and three women of age 67,4±7,1. With the use of surface electromyography, an activity was evaluated of m.tibialis anterior, m.gastrocnemius, m. rectus femoris, m. biceps femoris and mm. erectores spinae in place of Th -L junction. Acquired EMG signal was analized and then a standarized level of muscle activity during gait in different environments was evaluated, aground and in water, and afterward a dynamic co-contraction level was evaluated. Results: The results show consistent standardized activity of monitored muscles in water environment, which describes a chronic influence of pathological central program accompanying Parkinson's disease, where a change in coordination pattern is not observed, typical for movement in...
177

Porovnání timingu vybraných svalů pletence ramenního při plaveckém způsobu prsa ve vodě a na suchu / The Comparison of Muscle Timing of Chosen Shoulder Girdle Muscles During Breaststroke Inside and Outside the Water

Böswart, Jonáš January 2015 (has links)
Title: The Comparison of Muscle Timing of Chosen Shoulder Girdle Muscles During Breaststroke Inside and Outside the Water Objectives: The aim of this thesis was to compare timing and activation of chosen shoulder girdle muscles during breaststroke in the pool with counterflow and during excercise with rubber expander. Methods: It was analyzed timing and level of muscle activation during swimming and simulating the same movement of upper extremities in the air against the power of rubber expander. As an objetification was used surface electromyography. One profesional swimer took part in this experiment Results: Based on results it seemed that the movement of upper extremities are different in the pool and in the air during swimming stroke of breaststroke. Most of the measurement were different in the pool and in the air. Keywords: swimming, breaststroke, EMG, WaS-EMG, electromyography, shoulder girdle muscles, timing
178

Vliv typu povrchových elektrod na kvalitu dekompozice signálu povrchové elektromyografie / Effect of surface electrode type on quality of decopmposition of surface EMG signal

Strusková, Edita January 2012 (has links)
Title: Effect of surface electrode type on quality of decomposition of surface EMG signal Objectives: The aim of this thesis is to evaluate the effect of surface electrode type, which was used for EMG record, on the quality of decomposition of surface EMG signal using decomposition software EMGlab. Methods: The form of the thesis is an experimental essay. It was detected an EMG signal from one healthy volunteer during mild cyclic contraction. It was used three different types of electrodes (standard surface electrode, tetrode, tetrode with saw-off spikes) for EMG signal detection. These signals were decomposed in program EMGlab. The results were processed in program MS Excel, compared with each other and graphically displayed. Results: The measurement verified a hypothesis which claimed that the used type of electrode affects the quality of automatic decomposition. The best results of automatic decomposition provide the signal gained from the standard surface electrode. Key words: action potential, decomposition, surface electrodes, EMG signal, tetrode, electromyography
179

Hodnocení EMG aktivity svalů v oblasti pletence pažního při cvičení s Thera-Bandem ve vodním prostředí a na suchu / Evaluation of EMG Activity of the Shoulder Girdle Muscles during Exercises with Thera-Band in Aquatic Environment and on Land

Holländerová, Dita January 2011 (has links)
Title: Evaluation of EMG Activity of the Shoulder Girdle Muscles during Exercises with Thera-Band in Aquatic Environment and on Land. Objective: The main goal of this thesis is to determine a degree of muscle activity of upper trapezius muscle and other selected muscles in the aquatic environment and on land and to compare the values. Furthermore, to determine whether the upper trapezius muscle activates in the aquatic environment later than on land, compared to other selected muscles. Methods: This is the case of study, where the degree of muscle activity and the onset of activation of the upper trapezius muscle and other selected muscle is analyzed and then evaluated during shoulder abduction in two different environments using elastic resistance strength (yellow Thera-Band). As an objectification method surface electromyography had been chosen. To ensure the same set of initial conditions the abduction was performed in sitting position. The same chair was used in water and on land. Four female participants part in the experiment. Findings: The degree of muscle activity of upper trapezius muscle in the aquatic environment significantly decreased. It wasn't confirmed, that the upper trapezius muscle has been activated later in water than on land. Timing of selected muscles in aquatic environment...
180

Vliv Vojtovy reflexní lokomoce na pohybový aparát u pacientů s míšním poškozením / Vojta reflex locomotion impact to the locomotor system of the patients with spinal cord

Kohutová, Veronika January 2013 (has links)
The aim of this thesis was to evaluate the Vojta method therapy impact to the muscles function of the upper limbs of patients with tetraplegia. This is a pilot study, which was attended by five probands. To objectify the results, the method of surface electromyography was adopted. EMG activity of 14 muscles of the upper limbs and shoulder girdle during selected movements before and after therapy was recorded. The choice of therapeutic positions and activation zones was individual. Although a few muscles show significant changes, statistically considerable influence of the therapy cannot be confirmed from the obtained results. But from the point of view of clinical observation and patients 'subjective feelings an obvious difference can be seen. Therefore, it may be in the future advantageous to monitor the impact of Vojta method to locomotor system through clinical methods such as functional tests, tests of independence, range of motion or kinematic analysis.

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