Facial muscular training: the practice of speech-language pathologists from Belo Horizonte

PURPOSE: To verify the practice of the speech-language pathologist who acts in orofacial myology in Belo Horizonte - MG (Brazil) concerning facial muscular training, and to compare orofacial myology specialists and nonspecialists' conducts. METHODS: Sectional study, with application of a questionnaire to 60 speech-language pathologists (SLP) from Belo Horizonte - MG (Brazil) who attend orofacial myology patients: 30 graduate without specialization and 30 specialized in orofacial myology. The questionnaire presented a case report and 12 questions regarding conducts in myotherapy. Data analysis used Chi-square and Fisher's Exact Test, and considered a significance level of 5%. RESULTS: In the researched sample, 88.3% of the SLP mentioned isometric exercises, 63.3% requested a training frequency of three times a day and 81.7% seven days a week. The variation of time of muscular contraction was mentioned by 61.7%, and 40% recommend time increase. They indicated the need to vary the number of series of exercises along the therapeutic process in 50% of the interviews, and 26.7% of these mentioned decrease of this number. Regarding frequency, 43.3% considered necessary to vary the frequency of exercises along the therapeutic process: 20% reducing the number of repetitions of the exercise per day and 23.3% reducing the number of days a week. More than half of the professionals (56.7%) informed that the average time of intervention for orofacial myology varied from four to six months. CONCLUSION: The majority of the SLP interviewed for this study employ isometric exercises, three times a day, seven days a week, for an average period of four to six months of therapy. There was no significant difference between the conduct of specialized and nonspecialized speech-language pathologists.OBJETIVO: Verificar a prática do fonoaudiólogo que atua em motricidade orofacial em Belo Horizonte, acerca de treinamento muscular na face e comparar a conduta de profissionais com e sem especialização na área. MÉTODOS: Estudo transversal, com aplicação de questionário a 60 fonoaudiólogos de Belo Horizonte, atuantes em motricidade orofacial, sendo 30 sem especialização e 30 com especialização na área. O instrumento apresentou a descrição de um caso clínico e 12 perguntas acerca de condutas em mioterapia. Para análise dos dados foram empregados os testes qui-quadrado e exato de Fisher, sendo considerado um nível de significância de 5%. RESULTADOS: Na amostra pesquisada, 88,3% citaram exercícios isométricos, 63,3% indicaram freqüência de treinamento de três vezes ao dia e 81,7% sete dias por semana. A variação do tempo de contração muscular foi citada por 61,7%, sendo que 40,0% orientam aumento do tempo. Indicaram necessidade de variar o número de séries dos exercícios ao longo da terapia 50,0%, sendo que 26,7% destes citaram a diminuição. Quanto à freqüência, 43,3% consideraram necessário realizar variação ao longo da terapia, tendo 20,0% informado diminuir o número de vezes por dia e 23,3% diminuir o número de dias por semana. O tempo médio de quatro a seis meses para fonoterapia foi citado por 56,7% dos fonoaudiólogos. CONCLUSÃO: A maioria dos fonoaudiólogos citou empregar exercício isométrico, três vezes ao dia, sete dias por semana, com tempo médio de terapia entre quatro e seis meses. A conduta dos fonoaudiólogos com e sem especialização não apresentou diferença significante.Centro FEAD de FonoaudiologiaCentro de Estudos Superiores de Juiz de ForaUniversidade Federal de São Paulo (UNIFESP)Universidade Federal de Minas Gerais Departamento de FonoaudiologiaUNIFESPSciEL

Potenciais propagantes no músculo oblíquo interno por eletromiografia de superfície de alta densidade

Surface electromyography is a technique for capturing the electrical activity of the superficial muscles, but the potential of this technique in the capture of myoelectric signals of deep muscles has not been fully explored. High-density surface electromyography (HDEMG) allows the identification of potential propagators of a muscle with fibers parallel to the skin surface and was used in the present study to identify potential propagators in the internal oblique muscle, deep to the external oblique, with Matrix of 64 electrodes. A method for processing the EMG signals was proposed to estimate the direction of the action potentials of the motor units of the internal oblique muscle. The results showed that it was possible to identify propagating action potentials in the direction of the fibers in agreement with the architecture of the internal oblique muscle and to estimate the orientation of these fibers, in approximately 53 °. It’s concluded that the proposed method was able to detect potential propagators in the internal oblique deep muscle with the HD-EMG technique and can be used in studies of the action of this muscle in different motor tasks.A eletromiografia de superfície é uma técnica de captação da atividade elétrica dos músculos superficiais, porém o potencial desta técnica na captação de sinais mioelétricos de músculos profundos ainda não foi totalmente explorada. A eletromiografia de superfície de alta densidade (HD-EMG) possibilita a identificação de potenciais propagantes de um músculo com fibras paralelas à superfície da pele e foi utilizada no presente estudo, para identificar potenciais propagantes no músculo oblíquo interno, profundo ao oblíquo externo, com matriz de 64 eletrodos. Foi proposto um método para processamento dos sinais EMG para estimar a direção dos potenciais de ação das unidades motoras do músculo oblíquo interno. Os resultados mostraram que foi possível identificar potenciais de ação propagantes na direção das fibras condizente com a arquitetura do músculo oblíquo interno e estimar a orientação destas fibras, em aproximadamente 53°. Conclui-se que o método proposto foi capaz de detectar potenciais propagantes no músculo profundo oblíquo interno com a técnica de HDEMG e pode ser empregada em estudos da ação dessa musculatura em diferentes tarefas motora

Independent component analysis of high-density electromyography in muscle force estimation.

Item does not contain fulltextAccurate force prediction from surface electromyography (EMG) forms an important methodological challenge in biomechanics and kinesiology. In a previous study (Staudenmann et al., 2006), we illustrated force estimates based on analyses lent from multivariate statistics. In particular, we showed the advantages of principal component analysis (PCA) on monopolar high-density EMG (HD-EMG) over conventional electrode configurations. In the present study, we further improve force estimates by exploiting the correlation structure of the HD-EMG via independent component analysis (ICA). HD-EMG from the triceps brachii muscle and the extension force of the elbow were measured in 11 subjects. The root mean square difference (RMSD) and correlation coefficients between predicted and measured force were determined. Relative to using the monopolar EMG data, PCA yielded a 40% reduction in RMSD. ICA yielded a significant further reduction of up to 13% RMSD. Since ICA improved the PCA-based estimates, the independent structure of EMG signals appears to contain relevant additional information for the prediction of muscle force from surface HD-EMG

Tecniche e metodi per un'analisi multiscala del fenomeno della fatica muscolare

This thesis proposes an integrated holistic approach to the study of neuromuscular fatigue in order to encompass all the causes and all the consequences underlying the phenomenon. Starting from the metabolic processes occurring at the cellular level, the reader is guided toward the physiological changes at the motorneuron and motor unit level and from this to the more general biomechanical alterations. In Chapter 1 a list of the various definitions for fatigue spanning several contexts has been reported. In Chapter 2, the electrophysiological changes in terms of motor unit behavior and descending neural drive to the muscle have been studied extensively as well as the biomechanical adaptations induced. In Chapter 3 a study based on the observation of temporal features extracted from sEMG signals has been reported leading to the need of a more robust and reliable indicator during fatiguing tasks. Therefore, in Chapter 4, a novel bi-dimensional parameter is proposed. The study on sEMG-based indicators opened a scenario also on neurophysiological mechanisms underlying fatigue. For this purpose, in Chapter 5, a protocol designed for the analysis of motor unit-related parameters during prolonged fatiguing contractions is presented. In particular, two methodologies have been applied to multichannel sEMG recordings of isometric contractions of the Tibialis Anterior muscle: the state-of-the-art technique for sEMG decomposition and a coherence analysis on MU spike trains. The importance of a multi-scale approach has been finally highlighted in the context of the evaluation of cycling performance, where fatigue is one of the limiting factors. In particular, the last chapter of this thesis can be considered as a paradigm: physiological, metabolic, environmental, psychological and biomechanical factors influence the performance of a cyclist and only when all of these are kept together in a novel integrative way it is possible to derive a clear model and make correct assessments

Estimation of load sharing among muscles acting on the same joint and Applications of surface electromyography

The force produced by a specific muscle cannot be measured and what is measured is the total force provided by all the active muscles acting on a joint, including agonists and antagonists. The first part of this work (chapter 3) addresses the issue of load sharing by proposing two possible approaches and testing them. The second part (chapter 4 and 5) addresses two applications of surface EMG focusing on the study of a) muscle relaxation associated to Yoga sessions and b) the activation of muscle of the back and shoulder of musicians playing string instruments (violin, viola and cello). In both parts the element of innovation is the use of two dimensional electrode arrays and of techniques based on EMG Imaging. The objectives of this work are presented and explained in chapter 1 while the basic concepts of surface EMG are summarized in chapter 2. Different EMG-based muscle force models found in the literature are explained and discussed. Two renowned amplitude indicators in surface EMG (sEMG) studies are the average rectified value (ARV) and the root mean square (RMS). These two amplitude indicators are computed over a defined time window of the recorded signals to represent the muscle activity. The advantages and disadvantages of RMS and ARV are compared and discussed for a simple sinusoid as well as for more complex signals (simulated motor unit action potential detected by high density electrode grid). The results show that RMS is more robust to the sampling frequency than ARV. In this thesis, starting from the simulation of a single fiber and of a group of fibers (motor unit), it is shown that inter electrode distance (IED) greater than10 mm causes aliasing. Aliasing is a source of error in sEMG map interpretation or decisions that are made by automatic algorithms such as those providing image segmentation for the identifications of regions of interest. Chapter 2 discusses three segmentation algorithms (K-means, h-dome, watershed) and compares them in order to find the most suitable method. Results reveal that among the three mentioned algorithms, watershed provides most accurate segmentation for the simulated ARV maps. Chapter 3 presents a mathematical model that is associated to the monotonic Force-EMG relation. A possible non-linear relationship between the EMG and force or torque is presented. A system of "M" equations is obtained by performing "M" measurements at "M" different force levels in isometric conditions. The solutions of such system of equations are the values for each muscles. Two different approaches were investigated for finding the solutions of the system, which are: a) Analytical-Graphical Approach (AGA) and b) Numerical Approach (NA) consisting of error minimization (between the total estimated and measured force) applying optimization algorithms. The AGA was used to find the model parameters of each muscle contributing to the force production on a joint by finding the intersection of those surfaces that can be obtained from sequential substitutions of the model parameters in the equations corresponding to each contraction level. In simulation studies, the AGA graphically shows that there is more than one solution to the load sharing problem even for the simplest theoretical case (i.e. a joint spanned by only two muscles). The second approach, based on minimization of the mean square error between the measured and the total estimated force or torque (with "N" muscles involved) provides an estimate of the model parameters that in turn provides the force contributions of the individual muscles. The optimization algorithms can find the solutions of our system made of non-linear equations (see chapter 3). Starting from different point (initial conditions), different solutions can be found, as predicted by the AGA approach for the two-muscle case. The main conclusion of this study is that the load sharing strategy is not unique. Chapter 4 discusses the application of surface electromyography to a single case study of Yoga relaxation to show the feasibility of measurements. The effect of yoga relaxation on muscle activity (sEMG amplitude), as well as on mean and median frequencies and muscle fiber's conduction Velocity, is discussed in this chapter. No changes in the sEMG activity pattern distribution were found for the same task performed before and after applying yoga relaxation technique. However, myoelectric manifestations of fatigue were smaller after relaxation and returned to the normal pattern after the recovery phase from relaxation. Further studies are justified. Chapter 5 describes results and discusses the spatial distribution of muscle activity over the Trapezius and Erector Spinae muscles of musicians playing string instruments. In chapter 5, the effect of backrest support in sitting position during playing cello, viola, and violin on the muscle activity index of upper and lower Trapezius muscle of the bowing arm, upper Trapezius muscle of non-bowing arm, left and right Erector Spinae muscles is investigated. Two professional players (one cello and one viola) and five student players (one cello, three violin and one viola) participated in this study. The muscle activity index (MAI) was defined as the spatial average of RMS values of the muscle active region detected by watershed segmentation for Trapezius muscles (left and right), and thresholding technique (70% of the maximum value) for left and right Erector Spinae muscles. It was found that the MAI is string (note) dependent. Statistical difference (p < 0:05) between the MAIs of left Erector Spinae muscle during playing with and without backrest support was observed in four (out of five) student players. No statistical differences were observed on the muscle activity of Trapezius (bowing and no-bowing arms) during playing with and without backrest support in different types of bowing for all musicians. In conclusion, this work addresses a) the issue of spatial sampling and segmentation of sEMG using 2D electrode arrays, b) two possible approaches to the load-sharing issue, c) a single-case study of Yoga relaxation and d) the distribution of muscle activity above the Trapezius and Erector Spinae muscles of musicians playing string instruments. Previously unavailable knowledge has been achieved in all these four studies

Influencia de la fatiga sobre la variabilidad de la frecuencia cardiaca y los marcadores biológicos.

La fatiga es un fenómeno multifactorial dependiente del funcionamiento de varios sistemas en el organismo, comúnmente se le reconoce como la incapacidad en el sistema muscular para mantener una calidad de contracción muscular. El propósito de este estudio fue investigar la influencia generada por la fatiga sobre la variabilidad de la frecuencia cardiaca (VFC), marcadores biológicos y la electromiografía (sEMG) a través de cuatro tipos de ejercicio diferente. Esto fue basado en datos obtenidos de los marcadores de dominio de tiempo y del diagrama de Poincaré de la VFC, por la creatín kinasa, lactato y por la MPF y la Median de la sEMG en las pruebas isotónica, isométrica, anaeróbica y aeróbica. Metodología. 10 sujetos de estudio varones (media ± DE, edad 21.1 ± 1.72 años, estatura 173 ± 4.76 cm, peso 81.1 ± 16.71 kg, VO2max 47.8 ± 6.42 mL/kg/min) que fueron reclutados para el estudio para que desarrollaran una prueba de VO2max (test de control) y cuatro pruebas de distintas características con evaluaciones en reposo, al término de la prueba y en recuperación. Para los test isotónico e isométrico se realizó una prueba previa de 1RM, posteriormente se determinó el 30 % de la 1RM para realizar ambas pruebas, en la prueba isotónica se utilizó una frecuencia de 60 rpm y en la prueba isométrica una contracción sostenida, la prueba anaeróbica consiste en pedalear en un cicloergometro al 100 % de capacidad en watts del sujeto con una frecuencia de 60 rmp y en la prueba aeróbica se inicia con 100 watts de inicio durante los dos primeros minutos y un incremento gradual de 25 watts cada minuto, en todos los test desarrollados los sujetos ejecutaban sus movimientos hasta llegar al fatiga total. Los resultados de la VFC fueron obtenidos con el dispositivo Polar Team2 y los datos analizados en el software Kubios, los marcadores biológicos fueron analizados por medio del Reflotron en tiras reactivas para CK y el aparato YSI para lactato y los datos de electromiografía fueron analizados por medio de MATLAB una vez obtenidos del dispositivo Peak Motus. Resultados. En la prueba isométrica (b) los valores iniciales en reposo fueron de 67.94 ± 43.59 U/L y al final de la prueba de 87.62 ± 37.87 U/L con una diferencia significativa de p < 0.01 del resultado final de la prueba vs reposo. En la prueba anaeróbica (c) los valores de la toma en reposo fueron de 63.01 ± 31.55 U/L y al finalizar el test fueron de 109.4 ± 51.36 U/L presentando una diferencia significativa de p < 0.01 siendo en estas dos donde se vio una producción mayor, en el marcador biológico de lactato prueba isotónica (a) los valores en reposo previos al inicio de la prueba fueron de 2.43 ± 1.05 mmol/L y al final dieron valores de 4.67 ± 1.64 mmol/L que dio una diferencia significativa p < 0.01 vs la toma en reposo. En la prueba anaeróbica (c) los valores de lactato en reposo fueron 2.68 ± .67 mmol/L y finalizada la prueba fueron de 7.59 ± 1.65 mmol/L. En VFC en la variable MRR de dominio de tiempo en la prueba isotónica (a) hay una diferencia significativa p < 0.01 de la toma de recuperación vs reposo, y también de la toma de recuperación una diferencia significativa de p < 0.05 vs la toma final, la toma final tiene una diferencia significativa de p < 0.01 vs la toma en reposo, en la variable rMSSD en la prueba aeróbica (d) los resultados de la toma de recuperación tienen diferencia significativa p < 0.01 vs la toma en reposo, de igual manera presentaron los valores de la toma fina una diferencia significativa p < 0.01 vs la toma en reposo previa a la prueba, en la variable SD1 del diagrama de Poincaré en la prueba isométrica (b) la toma de recuperación tiene una diferencia significativa de p < 0.05 vs la toma final, la toma final tiene una diferencia significativa con la toma en reposo de p < 0.01 en esta prueba. En la electromiografía en la prueba de ejercicio isométrico (b) en la toma del primer cuartil los datos fueron de 86.08 ± 4.37 Hz, en el segundo cuartil 80.87 ± 5.38 Hz, tercer cuartil 75.23 ± 7.41 y en el cuarto cuartil fue 67.21 ± 10.79 Hz. Conclusión. Basados en las limitaciones y al nivel de los participantes de este estudio, concluimos que la VFC en sus variables de dominio de tiempo en conjunto con la acumulación de BLa y CK en sangre demostró que tienen la suficiente fortaleza en sus datos para ser utilizada con un indicador confiable de medición de las cargas de entrenamiento así como de su adaptación al proceso de entrenamiento. Este método de evaluación puede ser de fácil acceso a los entrenadores y jugadores para poder ajustar las intensidades y el volumen de los ejercicios en cada uno de sus entrenamientos. La VFC es una herramienta de mucha utilidad para monitorear el estado físico de los deportistas, siendo también es relevante mencionar que se obtuvieron resultados importantes para analizar el comportamiento de la fatiga en la actividad física cuando se utiliza la VFC en conjunto con los marcadores biológicos, ya que no podemos quedarnos en lo convencional de la evaluación del rendimiento deportivo sino por el contrario abrir el abanico de oportunidad sobre la obtención de resultados de la capacidad física de los atletas. En el comportamiento de los resultados quedo establecido en este documento que los ejercicios de tipo anaeróbico y aeróbico fueron los que generaron un nivel mayor de estrés en el organismo de los deportistas en la respuesta fisiológica obtenida por medio de la VFC y de igual manera se obtuvo un comportamiento similar en la predominancia al realizarse las mediciones de la creatín kinasa y el lactato

Ectopic Motor Unit Activity in Motor Neuron Disease

__Abstract__ Motor neuron disease (MND) is characterized by the progressive loss of motor neurons that control voluntary muscles. Due to its progressive nature, the muscles gradually lose their function leading to paralysis and, ultimately, death. The most common variant of MND is amyotrophic lateral sclerosis (ALS). Of all the people diagnosed with ALS, 50% die within approximately two to three years after their first symptoms arise and only about 20% live longer than 5 years [1]. Onset is typically around 50 - 70 years of age, but in some patients the onset may be much earlier, around the age of 20 - 30 years. Incidence is higher among men than women, estimated at 2:1 [2-4]. The first symptoms usually occur in the limbs, but muscle weakness may also begin in the bulbar region. Progressive weakness of the respiratory muscles leading to respiratory failure is the most common cause of death. Before the first clinical signs of muscle weakness become apparent, more than 50% of the motor neurons innervating a muscle may already be lost [5]. In the Netherlands, approximately 1,700 people (prevalence 10.3 per 100,000) suffer from ALS [2]. Every year, approximately 500 people (incidence 2.8 per 100,000) in the Netherlands are diagnosed with ALS [2], and about the same number of persons dies every year. In comparison, approximately 570 people in the Netherlands died in traffic accidents in 2013 [6]. The term ALS was first described in 1874 by Jean-Martin Charcot [7]. Despite the tremendous technological progress that has been made in the last 140 years and despite numerous studies that have been conducted to unravel the mechanisms that may cause this deadly disease, relatively little is known about the mechanisms that cause ALS and the progressive degeneration of motor neurons is often unpredictable. The great majority of patients is classified as having sporadic ALS, and only 5 - 10% of the patients have a familial history of this disease. A complex interaction between genetic and environmental factors is believed to contribute to the development of the disease. Several genes have been identified and their discovery gave new insights into the underlying pathophysiological mechanisms. At present, no cure is available, and the only approved and widely used medication (Riluzole) can only marginally slow down the progression of the disease by approximately 3 months [8]. In this section, first the concept of a motor unit as a crucial component being affected by MND will be introduced, together with some basics on how motor units are affected in this condition. Next, one of the most obvious clinical signs, fasciculations, will be discussed, followed by the varying clinical phenotypes. Subsequently, the difficulties in the diagnostic process and the prognosis will be described. Currently, both can be very difficult, especially in the early stages of the disease, even with a thorough clinical and electrodiagnostic examination

Faisabilité et intérêt du monitorage de la fatigue ventilatoire en anesthésie et réanimation par la mesure de l'électromyographie diaphragmatique temps réel

Muscular activity can be described in terms of performance and fatigue. Diaphragmatic muscle is charactarized by its resistance to fatigue, making of it a good representative of ventilatory autonomy. While of clinical interest, its measurement is difficult. We considered this measurement by analyzing the electrical diaphragmatic signal gathered from direct recordings. To be obtained, the parameters have to be filtered. We developped the tools to record as well as to filter the signal and have validated them in clinical settings during anesthesia and intensive care. A multielectrodes probe and the associated hardware and software were developped for the signal recording. The filtering which followed compared using differnt wavelet analysis algorithms (MuRw, LiFw), and a morphological filter (MoFi), through a RISC-ARM processor for a real-time measurement. MuRw was the best compromise for calcul duration and signal noise ratio. Clinical evaluation on patients and healthy volounteers demonstrated the pertinence of frequential parameters extracted from the filtered signal, particularly the High Low ratio obtained after spectral analysisL’activité musculaire peut être caractérisée par la performance et un état de fatigue. Le muscle diaphragmatique est caractérisé par sa résistance à la fatigue, en faisant un témoin de capacité à l'autonomie respiratoire. Bien que cliniquement d'intérêt, la mesure de l'état de fatigue de ce muscle est difficile. Nous avons approché cette mesure en analysant les signaux de son activité électrique recueillis par contact. L'obtention des paramètres requière un traitement du signal. Nous avons développé les outils de recueil et de traitement de ce signal et les avons analysé pendant l'anesthésie. Le recueil a fait l'objet du développement d'une sonde multiélectrodes et des logiciels hardware et software de recueil du signal. L'analyse du signal a été l'objet de différentes méthodes mathématiques de débruitage temps réel sur des processeurs RISC-ARM, comparant des algorithmes de deux types d’ondelettes (MuRw, LiFw), et un filtre morphologique (MoFi), le choix portant finalement sur l'ondelette MuRw offrant le meilleur compromis en temps de calcul et en rapport signal sur bruit. L'évaluation clinique de sujets sains et de patients a montré la pertinence des paramètres fréquentiels de l'activité électrique MuRw du diaphragme comme représentants de son état de fatigue, en particulier par le rapport hautes sur basses fréquences obtenu par analyse spectral