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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.
181

Deskripce kvadrupedálního lokomočního diagonálního vzoru při specifické sportovní lokomoci (šplh, chůze, shyb) / Description quadrupedal locomotion diagonal pattern in specific sport activity (rope climbing, walking, pull-up)

Bačáková, Radka January 2013 (has links)
Tittle: Description quadrupedal locomotion diagonal pattern in specific sport activity (rope climbing, walking, pull-up) Aim of work: The aim is to find a description kvadrupedal locomotion diagonal pattern with rope climbing and its motion pattern compared with the motion pattern of walking and pull-up. Methods: This work is descriptively-association study with quantitative and qualitative analysis. The dates were measured by surface electromyography and 2-D video-analysis. Results: Alternating activation of upper extremities (rope climbing without the lower extremities), we proved that the movement supporting lower extremities is quadruped locomotion diagonal pattern. Symmetric work of upper extremities (pull-up) is not in response at lower extremities quadruped locomotion diagonal pattern. Key words: Electromyography (EMG), quadruped, diagonal pattern, rope climbing, pull-up, walking
182

Bilateral muskelaktivering och effektutveckling : En observation av bilateral rörelse med armergometer / Bilateral muscle activation and power production

Karlsson, Laban, Åström, Marcus January 2018 (has links)
Syfte Syftet med studien var att observera bilateral effektutveckling, samt muskelaktivering i de övre extremiteterna. En bilateral övning observerades för att se om skillnader i muskelaktivering och effektutveckling fanns i dominant respektive icke dominant övre extremitet, samt diskutera dess implikationer. Metod Nio tränade deltagare fick utföra armcykling på en armergometer som modifierats så att rörelsen blev bilateral. Armcyklingen pågick i cirka åtta minuter med fyra belastningsnivåer (30W, 60W, 90W, 120W) där 50 RPM eftersträvades. Vid varje belastningsnivå registrerades effektutveckling och EMG under 30 sekunder. Medelvärdet av effektutvecklingen i dominant och icke dominant sida jämfördes med ett tvåvägs oberoende ANOVA. Resultat Vid effektutvecklingen hos dominant och icke dominant sida av kroppen fanns en statistisk signifikant skillnad mellan dominant och icke dominant sida F (3, 64) = 4.13, p = .046; med en medelstor effektstorlek (partial eta squared = .061) p-värdet sattes till .05. Icke dominant sida utförde mest arbete. Bakre deltoideus aktiverades generellt sett lika mycket i dominant och icke dominant sida, dock var icke dominant sida mer aktiv. De dominanta fingerflexorerna hade en större aktivering kontra de icke dominanta. Slutsatser Studien fann signifikant skillnad i effektutveckling av dominant och icke dominant sida av de övre extremiteterna där icke dominant sida gjorde ett större arbete. Muskel EMG visade stora individuella skillnader hos deltagarna. / Objectives The objective of the study was to observe bilateral power production and muscle activation in the upper extremities. A bilateral exercise was observed to see if differences in muscle activation and power production was present in dominant and non-dominant extremities, and furthermore discuss the implications. Method Nine trained participants performed arm cycling on a modified arm ergometer so the movement became bilateral. During eight minutes of cycling with four levels of intensity (30W, 60W, 90W, 120W) where 50 RPM was strived for. 30 seconds of power production and EMG data were recorded for each intensity. A two-way independent ANOVA was conducted on the mean values of power production of the dominant and the non-dominant side. Results There was a significant difference in the dominant and non-dominant side F (3, 64) = 4.13, p = .046; with a medium effect size (partial eta squared = .0.61) p value set to .05. The nondominant side did the majority of the work. The posterior deltoids had a similar muscle activation, however the non-dominant activated more. The dominant finger flexors activated more than the non-dominant with large individual differences within the sample group. Conclusions This study found significant differences in power production in the dominant and the nondominant side of the upper extremities. The non-dominant side had a greater power production. The EMG-data showed great individual differences within muscle activation.
183

Efeitos imediatos da eletroestimula??o nervosa transcut?nea e crioterapia na espasticidade e na atividade eletromiogr?fica de sujeitos hemipar?ticos

Martins, F?bio de Lima 29 October 2009 (has links)
Made available in DSpace on 2014-12-17T15:16:07Z (GMT). No. of bitstreams: 1 FabioLM.pdf: 1201794 bytes, checksum: a0d59fd87797a00a671d5be8a4198404 (MD5) Previous issue date: 2009-10-29 / Funda??o de Amparo a Pesquisa do Estado de S?o Paulo / Cerebrovascular accident (CVA) is a term used to characterize an ischemic or hemorrhagic vascular injury, which has got as main clinic manifestations, the motor and reflex function disturbance. In the first stage there is flaccidity and loss of voluntary movements that afterwards is substituted by mass patterns and spasticity. The spasticity brings with itself functional deficits and can generate negative impacts in various motor patterns. The aim of this research was to investigate the hyperreflexia and identify the immediate effects of transcutaneous nervous stimulation (TENS) and cryotherapy in the spasticity and electromyographic activity of hemiparetic subjects. The study is characterized as an almost experimental type, in which were selected, to compose the sample, 16 patients of both sex with CVA sequel. These individuals were evaluated by collecting the amplitude peak to peak and H reflex latency, Motor response (M response) in solear muscle and the electromyography (EMG) of the injured and healthy legs anterior tibial muscles. In the injured limb the evaluations occurred in different days for cryotherapy, TENS and control, in two moments, before and after the interventions. The healthy limb was evaluated one single time to serve as baseline, for comparison with the injured limb. It was used an statistic analysis, the t paired student test to identify the H reflex differences, latency and EMG of the injured and healthy limbs and to compare the results before and after the recourses application. The ANOVA for related samples was used to identify the differences among the recourses used. It was attributed for the statistic tests a significance level of 5%. The amplitude peak to peak of normalized maximum H reflex through the maximum motor response (Hmax/Mmax), showed itself significantly increased in the injured limb (p=0.0245). The H reflex latency was presented reduced in the injured limb (p=0, 0375). The electromyographic activity was showed decreased in the injured limb (p< 0.0001). After the TENS there was a Hm?x/Mm?x ratio decrease (0.60?0.16 versus 0.49.?0.18; P = 0.0006). Nonetheless, Just after the cryotherapy application there was an increase of Hm?x/Mm?x ratio (0.58 ? 0,15 to 0.77 ? 0.13, P=0,0007) and increase of signal latency (30.41 ? 1.87 versus 33.24 ? 2.19; P=0.0001). The electromyographic activity wasn t altered significantly by any resource. It was met statistic significant differences when the Hm?x/Mm?x P<0.0001) ratio and H reflex latency (P<0.0001) were compared between the post TENS, cryotherapy and control. One can conclude that the TENS can be used to spasticity immediate reduction, and that the cryotherapy can increase the hyperreflexia state in spastic patients. Nonetheless, the spasticity decrease or increase didn t provoke lectromyographic activity change in the muscle that is opponent to the spastic one / Acidente Vascular Encef?lico (AVE) ? o termo empregado para caracterizar uma les?o vascular isqu?mica ou hemorr?gica, que tem como principais manifesta??es cl?nicas, o dist?rbio da fun??o motora e reflexa. No est?gio inicial h? presen?a de flacidez e falta de movimentos volunt?rios, que posteriormente ? substitu?do por padr?es em massa e espasticidade. A espasticidade traz consigo d?ficits funcionais e pode gerar impactos negativos em diversos padr?es motores. O objetivo da pesquisa foi investigar os efeitos imediatos da eletroestimula??o nervosa transcut?nea (TENS) e crioterapia na espasticidade e na atividade eletromiogr?fica de sujeitos hemipar?ticos. O estudo caracteriza-se por ser do tipo quase experimental, no qual foram selecionados para compor a amostra, 16 pacientes de ambos os sexos com sequela de AVE. Estes indiv?duos foram avaliados captando-se a amplitude pico a pico e lat?ncia do reflexo H, resposta Motora (resposta M) no m?sculo solear e o eletromiograma (EMG) do m?sculo tibial anterior do membro comprometido e n?o comprometido. No membro comprometido as avalia??es ocorreram em dias diferentes para crioterapia TENS e controle, em dois momentos, antes e depois das interven??es. O membro n?o comprometido foi avaliado uma ?nica vez para servir como linha de base, para compara??o com o membro comprometido. Utilizou-se na an?lise estat?stica, o test t de student pareado para identificar as diferen?as do reflexo H, lat?ncia e EMG do membro comprometido e n?o comprometido e para comparar os resultados antes e depois da aplica??o dos recursos. A ANOVA para amostras relacionadas foi utilizada para identificar as diferen?as entre os recursos utilizados. Atribuiu-se para os testes estat?sticos o n?vel de signific?ncia de 5%. A amplitude pico a pico do reflexo H m?ximo normalizado pela resposta motora m?xima (Hm?x/Mm?x), mostrou-se significativamente aumentada no membro comprometido (p=0.0245). A lat?ncia do reflexo H reduziu no membro comprometido, com essa redu??o sendo estatisticamente significativa (p=0,0375). A atividade eletromiogr?fica se mostrou diminu?da no membro comprometido (p< 0.0001). Depois da TENS houve uma diminui??o da rela??o Hm?x/Mm?x (0.60?0.16 versus 0.49.?0.18; P = 0.0006). No entanto, logo ap?s a aplica??o do gelo houve um aumento da rela??o Hm?x/Mm?x (0.58 ? 0,15 para 0.77 ? 0.13, P=0,0007) e aumento da lat?ncia do sinal (30.41 ? 1.87 versus 33.24 ? 2.19; P=0.0001). A atividade eletromiogr?fica n?o foi alterada significativamente por nenhum recurso. Foram encontradas diferen?as estatisticamente significativas quando a raz?o Hm?x/Mm?x (P<0.0001) e lat?ncia do reflexo H (P<0.0001) foram comparadas entre o p?s-TENS, P?s- crioterapia e controle. Pode-se concluir que a TENS pode ser utilizada para fins de redu??o imediata da espasticidade, e que a crioterapia pode aumentar o estado de hiperreflexia nos pacientes esp?ticos. Entretanto, a diminui??o ou o aumento da espasticidade n?o ocasionou altera??o na atividade eletromiogr?fica do m?sculo antagonista ao esp?stico
184

Approche intégrative de détermination de la puissance maximale sur ergocycle lors de sprints de courte durée / Integrative approach of maximal power measurement during sprint exercises on cycle ergometer

Jaafar, Hamdi 11 December 2015 (has links)
L’objectif de ce travail de thèse était d’étudier, selon une approche intégrative, les facteurs intrinsèques et extrinsèques influençant les performances mécaniques et neuromusculaires lors d’exercices de sprint de courte durée sur ergocycle. La première étude a examiné l’effet du genre et le type d’exercice sur la reproductibilité des indices de la relation force-vitesse sur ergocycle. Les résultats ont révélé que la reproductibilité de la relation force-vitesse était plus élevée chez les hommes et au niveau des membres inférieurs comparativement respectivement aux femmes et aux membres supérieurs. La deuxième étude a investigué l’effet de deux charges (8,7 et 11% de la masse corporelle, BM) sur la reproductibilité des indices de puissance mécanique au court d’un test de Wingate. Les résultats ont révélé une reproductibilité comparable entre les deux charges. Cependant, la puissance était plus élevée à 11% BM. La troisième étude a comparé les indices de puissance de la relation force-vitesse et du test de Wingate selon l’aptitude anaérobie des sujets. Les résultats ont montré que la puissance maximale était sous-estimée lors des tests de Wingate réalisés contre des charges non optimales (8,7% BM) notamment chez les sujets sportifs. La quatrième étude a exploré l’effet du contexte émotionnel sur la performance neuromusculaire lors d’exercices de sprints répétés. Les résultats ont révélé un effet positif du contexte plaisant comparativement au contexte déplaisant sur la performance neuromusculaire. Ces résultats suggèrent que la motivation extrinsèque affecte, via la valence émotionnelle (plaisir-déplaisir), la performance lors des exercices maximaux de courte durée. / The aim of the present work was to study, using an integrative approach, the effects of intrinsic and extrinsic factors that influence the mechanical and neuromuscular performances during sprint exercises on a cycle ergometer. The first study examined the effect of exercise and gender on the reliability of the mechanical measurements from the force-velocity tests. The results showed that the reliability of the force-velocity test was higher in men and lower limbs compared to women and upper limbs, respectively. The second study investigated the effect of two loads (8.7 and 11% of body mass, BM) on the reproducibility of mechanical power indices during a Wingate test. The results showed comparable reliability between the two loads. However, power output was significantly higher at 11% BM. The third study compared power indices computed from the force-velocity and Wingate tests among two groups of male subjects with different physical fitness. The results showed that the Wingate tests performed against non-optimal loads (8.7% BM) underestimated maximal power especially in powerful subjects. The fourth study investigated the effect of the emotional context on neuromuscular performance during repeated cycling sprints. The results revealed a positive effect of pleasant context on neuromuscular performance compared to the unpleasant context. These results suggest that extrinsic motivation affects via the emotional valence (pleasant-unpleasant) the performance during all-out exercises.
185

MUSCLES ACTIVATIONS DURING "SHOULDER MOUNT" POLE ACROBATIC EXERCISE

Sanni, Modinat January 2016 (has links)
Author: Bc. Modinat Sanni Supervisor: Ing. Miroslav Vilímek, PhD Title: MUSCLES ACTIVATION DURING "SHOULDER MOUNT"POLE ACROBATIC EXERCISE Purpose: This study is an empirical - theoretical study presents the literature review regarding to the topic of the shoulder function anatomy, kinesiology, biomechanics, non-traumatic injuries of the shoulder and their prevention by using the available literatures. Further, the study also compares by surface electromyography the amplitudes, shapes and durations of myoelectric signals of m. latissimus dorsi, m. pectoralis maior, m. biceps brachii, m. infraspinatus and m. supraspinatus of dominant shoulder in two healthy individuals during acrobatic exercise on vertical pole known as "Shoulder Mount". The purpose was monitor the changes in two different conditions; i.e. kinesiotape and elbow brace and compare with the control condition for the reason of finding out their ability to affect the myoelectric activities of selected muscles. Further, the Shoulder Mount exercise had recorded by six Qualisys cameras for motion analyses. Methods and materials: The potentially eligible scientific articles perform a search of studies on the topic of kinesiotapes and tennis elbow brace as measured by EMG mainly on myoelectric activity of the shoulder complex were seared from...
186

Eletromyografická analyza cervikální flexe v závislosti na pozicích těla / Electromyographic analysis of the cervical flexion during different body positions

Sageshima, Hirofumi January 2020 (has links)
Author: Hirofumi Sageshima Title: Electromyographic analysis of the cervical flexion during different body positions Aim and Purpose: The aim of this study is to find out the muscle activity and the muscle coordination during cervical flexion in 3 different positions - standing, sitting and supine - with electromyographic analysis in young healthy adults. Methods: This study compared superficial cervical flexor muscles activity during conventional cervical flexion to 20 volunteered healthy subjects with surface electromyography (EMG). The activity of 5 paired muscles - sternocleidomastoid, scalenus, suprahyoid, infrahyoid and superior part of trapezius - were measured when they performed 15-time cyclic cervical flexion-extension from neutral to maximum cervical flexion on 3 different positions - sitting, standing and supine - in random order. Results: Significantly higher EMG amplitude was detected from all measured muscles on supine position than sitting and standing (p < 0.05). It was also confirmed that muscle activation pattern was different according to positions; its amplitude on supine reach the peak in the earlier phase of movement, while it was delayed on 2 other positions (p < 0.05). In terms of onset, all cervical flexors activated together in the very beginning. However, on sitting and...
187

Klassifikation funktioneller EMG-Signale des Nervus facialis zur Leistungssteuerung kraftgetriebener Instrumente

Kellermann, Niklas Philipp 11 December 2012 (has links)
Gegenstand dieser Arbeit ist die Klassifikation von funktionellen Elektromyographie-Signalen des Nervus facialis, die bei Parotidektomien und sanierenden Ohr-Operationen aufgezeichnet wurden. Hierfür wurde eine detaillierte Analyse der intraoperativ auftretenden Aktionen Stimulation, Koagulation, Einsatz der Fräse und Spülung an Hand von geeigneten Signalparametern (Amplitude, Dauer, Fläche/Symmetrie, Leistung und Frequenz) durchgeführt. Darüber hinaus erfolgte eine Gegenüberstellung der EMG-Daten der zwei durchgeführten operativen Eingriffe und ein Vergleich der zwei untersuchten Erfolgsorgane des Nervus facialis (Mm. orbiculares). Dabei zeigten sich in allen Parametern relevante Unterschiede zwischen den verschiedenen Kategorien. Auf Grund dieser Ergebnisse lässt sich schlussfolgern, dass es möglich ist, ein Klassifikationsschema für die intraoperativen EMG Signale des Nervus facialis zu entwickeln. Dieses ist unabhängig von der Art des durchgeführten Eingriffs und unabhängig vom beobachteten Fazialisast. Als weiterführendes Ziel soll diese Klassifikation der Kontrolle kraftgetriebener Instrumente nach dem Prinzip „Navigated Control“ dienen.
188

Étude comparative de l'initiation de la marche et du rattrapage de l'équilibre entre les enfants atteints de paralysie cérébrale et les enfants avec un développement normal / Comparative study of gait initiation and balance recovery between cerebral palsy and typical development children

Vo Toan, Trung 16 December 2015 (has links)
Les paradigmes expérimentaux de l'initiation de la marche (IM) et du rattrapage de l'équilibre (RE) consécutif à une chute-avant ont été choisis pour identifier les adaptations motrices éventuelles chez les enfants souffrant de lésions cérébrales (PC) bilatérales et unilatérales vs. les enfants avec un développement normal (DN). Les enfants PC et DN étaient âgés entre 5 et 16 ans. Les enfants PC avaient une marche autonome sans aide technique. Les résultats montraient que, dans l'IM, les différents groupes d'enfants présentent des patterns biomécaniques et d'activités EMG comparables lorsque l'appui est sain. Plus particulièrement, la présence d'un freinage de la chute pendant la phase pendulaire, qui est l'indice qui caractérise la maturation du processus de la marche, chez les plus jeunes PC indique l'absence de retard. Lorsque l'appui est sur le côté lésé, le freinage est absent voire faible. Cette absence de freinage peut être imputée à la modification de l'appui en équin. De même, les tracés biomécaniques et EMG dans RE montraient des patterns comparables entre les différents groupes d'enfants. Toutefois une différence remarquable peut être distinguée par rapport à l'activité EMG des muscles fléchisseurs plantaires et dorsaux des adultes. Chez les adultes, la chute provoque une réponse précoce bilatérale des Soleus accompagnée parallèlement d'une activité de faible amplitude des TA. Chez les enfants, les TA montraient une importante bouffée EMG en même temps que la bouffée du Soleus. La suppression de cette bouffée précoce lorsque la chute est rapidement arrêtée annihilant l'exécution du pas suggère que les enfants DN et PC déclencheraient en même temps la réaction à la chute et le programme d'initiation du pas. Si les enfants PC pouvaient réalisés les deux tâches motrices, exécution du pas normal et exécution du pas provoqué, c'est semble-t-il grâce à la toxine botulique qui avait permis à l'enfant PC de se mettre debout libre, apprendre à contrôler son équilibre postural et la marche. / Experimental paradigms of gait initiation (GI) and balance recovery (BR) following a forward-fall were chosen to study motor adaptation in cerebral palsy (CP) children as compared to typical development children (TD). Children age ranged between 5 and 16 y.o. PC children walked independently. Results in GI showed that biomechanical and EMG pattern are comparable between the different groups when stance foot was on sound side. More particularly, the presence of fall braking during swing phase, which is a maturation index of gait process, in young CP indicates that there is no delay. When stance foot is on affected side, fall braking is absent that can be explained by equines foot. In BR, biomechanical and EMG traces are comparable between the different groups. However, if compare to adults, there is a striking difference in the EMG patterns. In adults, the fall elicited a bilateral burst of EMG in Soleus muscle, in parallel Tibialis anterior (TA) showed concomitant EMG activity but with lower amplitude. In children, TA showed a burst of EMG activity in parallel to SOL. This TA EMG burst was suppressed whether the fall was arrested annihilating the stepping. This result suggests that children trigger at the time the fall reaction program and the stepping program. If CP children can carry out both motor tasks, normal stepping and provoked stepping, this was thanks to use of botulinum toxin which help children standing up. Then, the mechanism of balance control can operate, and supporting gait acquisition.
189

Deskripce kvadrupedálního lokomočního diagonálního vzoru při specifické sportovní lokomoci (šplh, chůze, shyb) / Description quadrupedal locomotion diagonal pattern in specific sport activity (rope climbing, walking, pull-up)

Bačáková, Radka January 2013 (has links)
Tittle: Description quadrupedal locomotion diagonal pattern in specific sport activity (rope climbing, walking, pull-up) Aim of work: The aim is to find a description kvadrupedal locomotion diagonal pattern with rope climbing and its motion pattern compared with the motion pattern of walking and pull-up. Methods: This work is descriptively-association study with quantitative and qualitative analysis. The dates were measured by surface electromyography and 2-D video-analysis. Results: Alternating activation of upper extremities (rope climbing without the lower extremities), we proved that the movement supporting lower extremities is quadruped locomotion diagonal pattern. Symmetric work of upper extremities (pull-up) is not in response at lower extremities quadruped locomotion diagonal pattern. Key words: Electromyography (EMG), quadruped, diagonal pattern, rope climbing, pull-up, walking
190

Decomposição de sinais mioelétricos superficiais: avaliação não-invasiva de desordens neuromusculares / Surface mioeletric signals decomposition: non-invasive evaluation of neuromuscular disorders

Samuel Waldemar Andrade Flôr 18 August 2003 (has links)
Informações sobre as características funcionais e estruturais da unidade motora (UM) são altamente relevantes em investigações fisiológicas e nos estudos clínicos das disfunções neuromusculares. A eletromiografia (EMG) é um método adequado para obtenção dessas informações. Entretanto, devido à dificuldade na separação da atividade individual de uma unidade motora das outras que estão simultaneamente ativas, seu uso em clínica prática se dá comumente através de métodos invasivos, empregando eletrodos de agulha ou fios implantados. Apesar da EMG de superfície ser não-invasiva e, portanto mais apropriada para aplicações clínicas, não é usada em clínica porque não há até o presente um método satisfatório para decomposição do sinal EMG de superfície. Um EMG de superfície é muito mais difícil de decompor devido a significante superposição dos Potenciais de Ação das UMs (MUAPs) e a relação sinal-ruído relativamente baixa, se comparada aos métodos invasivos. Defendemos que a separação da atividade individual das UMs pode ser feita de modo não-invasivo aliando-se técnicas de aquisição altamente especializadas com técnicas usadas em reconhecimento de padrões. Desenvolvemos um método para decomposição de EMGs de superfície, a partir do qual foi possível extrair características relevantes das UMs, que permitem seu uso em avaliação e diagnóstico de desordens neuromusculares. Em nossa abordagem, o sinal EMG é inicialmente captado sob contração isométrica fraca usando eletrodos desuperfície. O sinal EMG bruto passa em seguida por um filtro Diferencial Passa-Baixas Ponderado (DPBP) em série com um detector de picos, que detecta os picos de MUAPs e extrai suas formas de onda. Na sequência, o conjunto de MUAPs extraído é classificado por uma rede neural SOM, e os MUAPs agrupados pela similaridade de suas formas de onda. No próximo passo a informação temporal dos disparos é checada, eliminando possíveis erros de classificação, e finalmente os Trens de MUAPs (MUAPTs) das UMs individuais são reconstituídos do EMG original. As estatísticas de disparos (IPI) bem como as formas de ondas dos MUAPs das respectivas UMs são então extraídas e armazenadas para estudos posteriores. Resultados preliminares obtidos com EMGs normais e patológicos, extraídos de membros superiores sob contração fraca, indicam que, o método mostrou-se apto a decompor EMGs de superfícies, além de potencial para aplicações em estudos clínicos não-invasivos de disfunções neuromusculares.Informações sobre as características funcionais e estruturais da unidade motora (UM) são altamente relevantes em investigações fisiológicas e nos estudos clínicos das disfunções neuromusculares. A eletromiografia (EMG) é um método adequado para obtenção dessas informações. Entretanto, devido à dificuldade na separação da atividade individual de uma unidade motora das outras que estão simultaneamente ativas, seu uso em clínica prática se dá comumente através de métodos invasivos, empregando eletrodos de agulha ou fios implantados. Apesar da EMG de superfície ser não-invasiva e, portanto mais apropriada para aplicações clínicas, não é usada em clínica porque não há até o presente um método satisfatório para decomposição do sinal EMG de superfície. Um EMG de superfície é muito mais difícil de decompor devido a significante superposição dos Potenciais de Ação das UMs (MUAPs) e a relação sinal-ruído relativamente baixa, se comparada aos métodos invasivos. Defendemos que a separação da atividade individual das UMs pode ser feita de modo não-invasivo aliando-se técnicas de aquisição altamente especializadas com técnicas usadas em reconhecimento de padrões. Desenvolvemos um método para decomposição de EMGs de superfície, a partir do qual foi possível extrair características relevantes das UMs, que permitem seu uso em avaliação e diagnóstico de desordens neuromusculares. Em nossa abordagem, o sinal EMG é inicialmente captado sob contração isométrica fraca usando eletrodos desuperfície. O sinal EMG bruto passa em seguida por um filtro Diferencial Passa-Baixas Ponderado (DPBP) em série com um detector de picos, que detecta os picos de MUAPs e extrai suas formas de onda. Na sequência, o conjunto de MUAPs extraído é classificado por uma rede neural SOM, e os MUAPs agrupados pela similaridade de suas formas de onda. No próximo passo a informação temporal dos disparos é checada, eliminando possíveis erros de classificação, e finalmente os Trens de MUAPs (MUAPTs) das UMs individuais são reconstituídos do EMG original. As estatísticas de disparos (IPI) bem como as formas de ondas dos MUAPs das respectivas UMs são então extraídas e armazenadas para estudos posteriores. Resultados preliminares obtidos com EMGs normais e patológicos, extraídos de membros superiores sob contração fraca, indicam que, o método mostrou-se apto a decompor EMGs de superfícies, além de potencial para aplicações em estudos clínicos não-invasivos de disfunções neuromusculares. / Information on the functional and structural characteristics of the motor unit (MU) they are highly important in physiologic investigations and in the clinical studies of the neuromuscular dysfunctions. The electromyography (EMG) it is an appropriate method for obtaining of that information. However, due to the difficulty in the separation of the individual activity of a motor unit of the another that are simultaneously active, your use in practical clinic happen commonly through methods invasive, employing needle electrodes or implanted threads. In spite of surface EMG to be non-invasive and, therefore more appropriate for clinical applications, it is not used at clinic because there is not until the present a satisfactory method for decomposition of the surface EMG sign. A surface EMG is much more difficult of decomposing due to significant overlap of the Motor Unit Action Potentials (MUAPs) and the relationship sign-noise relatively low, if compared to the invasive methods. We defended that the separation of the individual activity of MUs can be made in way non-invasive allying highly specialized acquisition techniques with techniques used in recognition of patterns. We developed a method for decomposition of surface EMGs, starting from which was possible to extract important characteristics of MUs, which allow your use in evaluation and diagnosis of neuromuscular disorders. In our approach, the sign EMG is captured initially under weak isometriccontraction using surface electrodes. The sign EMG raw raisin soon after for a Biased Low-Pass Differential filter (BLPD) in series with a detector of peaks, that detects the peaks of MUAPs and it extracts your wave forms. In the sequence, a SOM neural network classifies the set of extracted MUAPs, and MUAPs are clustered by the similarity in your wave shape. In the next step the temporal information of the discharges is checked, eliminating possible classification mistakes, and finally the MUAPs Trains (MUAPTs) of individual MUs they are reconstituted of original EMG. The statistics of discharges (IPI) as well as the forms of waves of MUAPs of respective MUs are then extracted and stored for subsequent studies. Results preliminaries obtained with normal and pathological EMGs, extracted of superior members under weak contraction, they indicate that, the method was shown capable to decompose surfaces EMGs, besides potential for applications in clinical studies non-invasive of neuromuscular dysfunctions.

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