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Introdução. O sangramento causado pelo cavernoma pode levar a déficits focais, afetando a articulação do tornozelo, dificultando a dorsiflexão, atividades funcionais decorrentes deste movimento e o desenvolvimento da marcha. A plataforma baropodométrica permite a visualização de variáveis oriundas do tornozelo. Objetivo. Verificar a efetividade da interface MESs-FESs associada a exercícios de reabilitação neurofuncional sobre a dorsiflexão de tornozelo e execução da marcha em um indivíduo após sangramento intraparenquimatoso por cavernoma. Método. Estudo de caso com uma participante avaliada por meio da (i) escala modificada de Ashworth, (ii) goniometria, (iii) eletromiografia de superfície (os dados foram normalizados) e (iv) baropodometria estática e dinâmica. A intervenção foi realizada em 6 sessões com duração de 30 minutos, onde a interface MESs-FESs era associada a exercícios de reabilitação. Resultados. O músculo tibial anterior não obteve aumento no seu valor eficaz (EMGRMS), porém, o músculo gastrocnêmio medial apresentou uma redução no EMGRMS de 55% durante a marcha, levando a um aumento de 30% da ADM, na baropodometria detectou-se maior simetria nas respostas plantares durante o ortostatismo, durante a marcha houve melhora no posicionamento do calcanhar, durante o contato inicial, e aplainamento do pé com subsequente maior tempo de apoio no membro acometido. Adicionalmente, foi observado melhora na mobilidade de tornozelo. Conclusão. A associação da interface MESs-FESs com exercícios de reabilitação mostrou ser efetiva como instrumento de auxílio no tratamento de sequelas de paresia do tornozelo. Sendo uma ferramenta viável e segura para inserção no ambiente clínico.

Acquiring biopotentials with fidelity using low-cost circuits is a significant challenge in biomedical instrumentation. In this perspective, our goal is to investigate the characteristics of the widely applied AD8232®, an analog front-end for biopotential acquisition. We designed and evaluated circuits to acquire the most common biosignals: electrocardiogram (ECG), electromyogram (EMG), and electroencephalogram (EEG). Our findings show that the circuit is suitable for ECG and EMG instrumentation, although it has limitations for EEG signals, particularly concerning the gain. The entire project of the boards is also a contribution of this work as we intend to corroborate open-source do-it-yourself biomedical instrumentation.

Objetivo. A eletromiografia (EMG) capta ativação do motoneurônio e aciona a estimulação elétrica funcional (FES) promove contração muscular que mimetiza ativação muscular e promove neuroplasticidade. A interface EMG-FES é a interação de ambos os dispositivos, seu uso no presente estudo tem como objetivo verificar seu efeito modulador na abertura da mão em participantes pós–acidente vascular cerebral (AVC). Método. Foram realizadas 4 avaliações: (1) antes da intervenção, (2) após 8 sessões, (3) após 16 sessões e (4) acompanhamento após 15 dias da última intervenção. Foram feitas EMG de superfície nos músculos: (i) extensores de dedos, (ii) extensor do indicador, (iii) abdutor do polegar e (iv) flexor dos dedos. Foram realizadas 8 ou 16 sessões de ~30 minutos de duração de aplicação da interface EMG-FES nos músculos extensores de dedos. Resultados. Foram contatados 431 e selecionados 4 participantes para o protocolo. Em dois dos participantes foram realizadas 8 sessões e nos outros dois, 16. A EMG registrou aumento do sinal e a taxa de disparo neural dos músculos avaliados na segunda e terceira avaliação, respectivamente. Nas avaliações seguintes houve diminuição dos valores, exceto nos músculos flexores dos dedos. Conclusão. A interface EMG-FES indicou que funciona para aumentar a ativação muscular e a taxa de disparo neural. Na avaliação de acompanhamento houve regressão dos valores, indicando melhora apenas a curto prazo. Para otimização da aplicação da interface EMG-FES sugere-se associá-la à exercícios resistidos e/ou terapia espelho.

Spasticity is a motor condition present in 75 to 88% of children with Cerebral Palsy (CP). One form of treatment is called punctual mechanical oscillation (PO). The current study aimed to study different protocols for the application of PO and the magnitude of their effects. In total, 7children with medical diagnosis of CP and ICD (International Classification of Diseases) were included. The first intervention protocol (Int1) consisted of the application of PO to the spastic muscle tendon and the second intervention protocol (Int2) to the muscle belly ofthe spastic antagonist muscle. For evaluation, the Modified Ashworth Scale (MAS) was used, while simultaneously capturing the mechanomyography (MMG) signals. Data were collected pre-intervention and 1 (Post1), 15 (Post15), 30 (Post30), 45 (Post45), and60 (Post60) minutes after the interventions. The MAS values (median ± interquartile range) post intervention were statistically lower when compared to the pre values in the 2 protocols studied; in Int1between Pre (2 ± 0) andPost15 (0 ± 1.75), Post30 (0 ± 1), Post45 (1 ± 1),and Post60 (1 ± 1), and in Int2only between Pre (2 ± 1) and Post1 (0 ± 1).The values found in the MMG in both its temporal and spectral domains did not follow a pattern (p>0.05). The comparison between the protocols did not demonstrate statistical differences in any characteristics (MAS, MMGMF, and MMGRMS). However, PO was shown to be a therapeutic resource that modulated spasticity for up to 60 minutes after its application, and PO could contribute as a tool to aid the treatment of spasticity. Introdução: A espasticidade é uma condição motora presente em 75 a 88 % das crianças com Paralisia Cerebral (PC). Uma forma de tratamento é a chamada oscilação mecânica pontual (OP). Este trabalho teve por objetivo estudar diferentes protocolos de aplicação da OP e a magnitude de seus efeitos. Métodos: Foram incluídas 7 crianças com diagnóstico médico de PC e CID (Classificação Internacional de Doenças). O primeiro protocolo de intervenção (Int1) consistiu na aplicação de OP no tendão do músculo espástico e o segundo protocolo de intervenção (Int2) no ventre muscular do músculo antagonista espástico. Para avaliação, foi utilizada a Escala Modificada de Ashworth (EMA), capturando simultaneamente os sinais da mecanomiografia (MMG). Os dados foram coletados antes da intervenção e 1 (Pós1), 15 (Pós15), 30 (Pós30), 45 (Pós45) e 60 (Pós60) minutos após as intervenções. Resultados: Os valores do MAS (mediana ± intervalo interquartil) pós-intervenção foram estatisticamente menores quando comparados aos pré-valores nos 2 protocolos estudados; no Int1 entre Pré (2 ± 0) e Pós15 (0 ± 1,75), Pós30 (0 ± 1), Pós45 (1 ± 1) e Pós60 (1 ± 1) e no Int2 apenas entre Pré (2 ± 1) e Pós1 (0 ± 1). Os valores encontrados no MMG nos domínios temporal e espectral não seguiram um padrão (p> 0,05). Conclusão: A comparação entre os protocolos não demonstrou diferenças estatísticas em nenhuma característica (EMA, MMGMF, and MMGRMS). No entanto, a OP mostrou-se um recurso terapêutico que modulou a espasticidade por até 60 minutos após a sua aplicação, e a OP poderia contribuir como uma ferramenta para auxiliar o tratamento da espasticidade.

Made available in DSpace on 2021-06-25T10:29:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-07-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) People with spinal cord injury (SCI) may have their paralyzed muscles activated through functional electrical stimulation (FES). This neuromodulation technique has been used frequently to assist in controlling the movement of neuroprostheses. Electroencephalography (EEG) is able to trigger FES from the motor imagery captured through movements intentions. This research presents an isometric neuromuscular control system of the quadriceps muscle activated by EEG. Additionally, the detection of neuromuscular fatigue through the mechanomyography (MMG) technique is proposed, which is used to shut-off the system. A pilot study was performed on a chronic 42-year-old paraplegic (no voluntary contraction below the spinal cord injury level T8) volunteer. To do so, the training procedure for EEG signals was divided into the calibration and feedback phases. In the first one, four EEG channels and the Linear Discriminant Analysis (LDA) classifier were used to classify between motor imagery of the right leg and remain at rest. The maximum accuracy obtained during this stage was 77%. In the feedback phase, the volunteer was able to activate FES through brain–computer interface (BCI) in two tests (defined as Test 1 and Test 2) with the same procedure in different days. The closed-loop force control was tested with the setpoint of 2 kgf and 2.5 kgf and proved to be stable on both tests, successfully turning off the FES using the fatigue threshold from the MMG signal, being the main contribution of this work. Universidade Estadual Paulista Júlio Mesquita Filho (UNESP) Faculdade de Engenharia Campus Ilha Solteira, Av. Brasil Sul, 56 Universidade Tecnológica Federal do Paraná (UTFPR), Marcílio Dias, 635 Universidade Tecnológica Federal do Paraná (UTFPR), Avenida Sete de Setembro 3165 Universidade Estadual de Londrina (UEL) – Departamento de Anatomia Laboratório de Engenharia Neural e de Reabilitação, Rodovia Celso Garcia Cid – Pr 445, Km 380 Instituto Senai de Tecnologia da Informação e Comunicação (ISTIC) Laboratório de Sistemas Eletrônicos - Embarcados e de Potência IoT e Manufatura 4.0, Rua Belém 844 Universidade Estadual Paulista Júlio Mesquita Filho (UNESP) Faculdade de Engenharia Campus Ilha Solteira, Av. Brasil Sul, 56

O estudo da Anatomia Humana (AH) é parte integrante e de relevância inquestionável na graduação dos cursos da saúde. Com a constante redução na carga horária destinada à AH e diante dos debates sobre os novos métodos de ensino, o uso do código de quick response (código QR) se mostrou promissor. Nesse sentido, foi desenvolvido no Departamento de Anatomia da Universidade Estadual de Londrina (UEL) o processo de catalogação das estruturas anatômicas com o uso do código QR, sendo nosso objetivo relatar esta experiência. Neste processo, as estruturas dissecadas no Laboratório de Anatomia da UEL foram catalogadas com base em uma planilha contendo a correlação entre estruturas e números e, as informações de cada estrutura transcritas em um código QR através de um gerador eletrônico, sendo então impresso, plastificado e anexado à peça anatômica. As marcações foram realizadas por meio da sutura de etiquetas enumeradas. Dentro da discussão dos métodos alternativos de ensino há como exemplos a plastinação, a projeção em três dimensões e a prospecção. Em destaque neste relato, o uso do código QR mostrou-se como uma alternativa válida na agregação de conhecimento nos currículos acadêmicos. Por meio das atividades empreendidas no processo de catalogação, foi possível, além da aquisição de mais tempo dedicado ao conhecimento teórico-prático em AH, ampliar a independência no estudo e no desenvolvimento de pesquisas. Dessa forma, tem-se a oportunidade de se expandir as análises voltadas ao ensino da AH e aos novos métodos de aprendizado.

Neuromuscular electrical stimulation (NMES) is a common tool that is used in clinical and laboratory experiments and can be combined with mechanomyography (MMG) for biofeedback in neuroprostheses. However, it is not clear if the electrical current applied to neuromuscular tissues influences the MMG signal in submaximal contractions. The objective of this study is to investigate whether the electrical stimulation frequency influences the mechanomyographic frequency response of the rectus femoris muscle during submaximal contractions. Thirteen male participants performed three maximal voluntary isometric contractions (MVIC) recorded in isometric conditions to determine the maximal force of knee extensors. This was followed by the application of nine modulated NMES frequencies (20, 25, 30, 35, 40, 45, 50, 75, and 100 Hz) to evoke 5% MVIC. Muscle behavior was monitored by the analysis of MMG signals, which were decomposed into frequency bands by using a Cauchy wavelet transform. For each applied electrical stimulus frequency, the mean MMG spectral/frequency response was estimated for each axis (X, Y, and Z axes) of the MMG sensor with the values of the frequency bands used as weights (weighted mean). Only with respect to the Z (perpendicular) axis of the MMG signal, the stimulus frequency of 20 Hz did not exhibit any difference with the weighted mean (P = 0.666). For the frequencies of 20 and 25 Hz, the MMG signal displayed the bands between 12 and 16 Hz in the three axes (P

Introduction Military police activity individuals performing operational activity remain 12 hours using mandatory safety equipment. This work aimed to verify the electromyographic response in operational military police officers before and after a cycle of two working days. Methods Forty-four male individuals were evaluated, with an average age of 34.59 ± 8.05. The used protocol consisted in the evaluation of paravertebral muscles and rectus abdominis muscles in a maximum isometric voluntary contraction test (MVC) during trunk extension movements, starting from the sitting position. Moreover, the Roland-Morris functional evaluation questionnaire and the Corlett and Manenica diagram for painful areas were used. An electromyograph with 16 pre-set channels was used. Signals were processed in time (EMGME) and spectral (EMGMF) domains, using the MatLab® program. The Shapiro-Wilk test and Wilcoxon Signed Ranks Test were applied. Statistical analyses were performed through the SPSS v21.0 software and Microsoft Office Excel 2010, considering p < 0.05 as significance level. Results Results showed statistical differences in the post-working day for time analysis, an EMGME decrease in the right rectus abdominis muscle (p = 0.016) and in the age-stratified sample, with individuals over 31 years old (p = 0.016); in the spectral analysis, EMGMF reduction in the right iliocostalis (p = 0.027) and right and left side in the stratified sample, in individuals over 31 years old and with more than 10 years of service. Conclusion The used protocol highlighted a decrease in the amplitude of the electromyographic signal, as well as possible muscle fatigue on the right side where officers usually carry their weapons.

A motor neural prosthesis based on surface functional electrical stimulation (sFES) can restore functional movement (e.g., standing, walking) in patients with a spinal cord injury (SCI). sFES generates muscle contractions in antigravity muscles and allows balance-assisted standing. This induced standing has several benefits, such as improved cardiovascular function, decreased incidence of urinary infections, reduced joint contractures, and muscle atrophy. The duration of sFES assisted standing is limited due to the quick onset of muscle fatigue. Currently, there is no method available to reliably estimate real-time muscle fatigue during sFES. Simply monitoring the M-wave changes is not suitable due to the high signal disturbances that arise during multi-channel electrical stimulation. Mechanomyography (MMG) is immune to electrical stimulation artifacts and can be used to detect subtle vibrations on the surface of the skin related to activation of the underlying muscle's motor units (MU). The aim of this study was to develop a method for detecting muscle fatigue brought on by sFES. The method was tested in three different heads of the quadriceps muscle in SCI patients during electrically elicited quasi-isometric contraction. Six spinal cord-injured male volunteers, with no voluntary control of the quadriceps muscle participated in the study. Electrical bursts of voltage-controlled monophasic square pulses at frequencies of 1 kHz (50% duty cycle) at 50 Hz (15% duty cycle) were used to generate thigh muscle contractions that controlled the knee joint in the sagittal plane. The pulse amplitudes were set to position the knee joint at a 5° angle from the horizontal plane and when the knee angle dropped to 20° (e.g., the quadriceps were unable to hold the lower leg in the desired position), the test was terminated. Two data segments lasting 10 s each, at the beginning and end of each test, were analyzed. The muscle contraction was assessed by MMG sensors positioned on the rectus femoris, vastus lateralis, and vastus medialis muscles. Data segments were decomposed into 11 frequency bands using a Cauchy wavelet transform. In the initial time interval (non-fatigued muscle), the power peak was concentrated in the 11.31 Hz frequency band. In the final interval (muscle fatigued) this peak shifted to lower frequencies (2 and 6 Hz frequency bands). The decreased frequency was most prominent during the last 4 s of the recordings. It was shown that MMG could be used as a real-time indicator of muscle fatigue during FES-induced isometric contraction of quadriceps; hence, MMG could be used in closed-loop control as a fatigue detector. Subsequent studies for non-isometric contractions could possibly lead to prediction of muscle fatigue before contractile failure during functional use of the muscle.

The core muscles can be evaluated through functional tests, such as the prone bridge test (PBT) and supine unilateral bridge test (SUBT). However, there are differences in reliability and muscle fatigue related to these tests.The study evaluated 30 sedentary individuals and 30 individuals who practiced resistance exercises. Participants performed the PBT and SUBT in association with muscle recruitment, through surface electromyography of the upper and lower limbs and trunk muscles. The order of the tests was random and the participants performed one repetition of each test until fatigue. After a 30-min rest interval the participants repeated the tests. After one week, the participants returned and repeated the tests.The resistance group (RG) presented longer PBT holding time (RG 111.8 ± 9.4 and sedentary group (SG) 81 ± 7.7; p = 0.01), while the holding time in the SUBT was similar for both groups (RG = 100.7 ± 8.1 and SG = 79 ± 9.2; p = 0.09). Good to excellent reliability (ICC0.836; SEM 3.85) was established for the PBT and SUBT. Comparing the two groups there were no significant differences or interactions regarding muscle fatigue. The intragroup analysis on the PBT indicated greater gluteus maximus muscle fatigue, and for the SUBT the rectus abdominis presented greater fatigue, in both groups.The PBT and SUBT are reliable. Resistance exercise practitioners maintain the PBT for a longer time. The PBT led to greater gluteus maximus muscle fatigue, while the SUBT generated greater fatigue in the rectus abdominis and gluteus medius, in both groups.

Functional electrical stimulation (FES) is a method of activating paralyzed muscles. During FES application, fast muscle fatigue can occur (the inability of stimulated muscles to generate force). Therefore, it is beneficial to estimate the muscle fatigue for FES closed-loop control for walking to prevent unexpected muscle collapse and adapt the FES strategy in real time. Mechanomyography (MMG) is a noninvasive technique for registering myofiber vibrations, representing an ideal candidate for the provision of feedback. The hypothesis was that MMG signals could effectively detect muscle fatigue and, thus, provide feedback. We tested this hypothesis by analyzing the wavelet transform of signals from an MMG sensor positioned over the rectus femoris muscle during electrically evoked contractions in subjects with spinal cord injury (SCI). The signals were collected from a total of 24 lower limb muscles. We investigated both legs of 15 participants with spinal cord injury (male, YOA = 27.13 ± 5.05, M = 75.8 ± 10.35 kg, and H = 1.78 ± 0.07 m, American Spinal Injury Impairment Scale (AIS) A and B). All MMG signals were analyzed in 12 frequency bands from 5 to 53 Hz. We found different trends in the magnitudes in different frequency bands. The magnitude decreased in 13, 16, 20, 25, and 35 Hz bands in correlation with fatigue. The greatest statistical difference was found at 20 Hz and 25 Hz. This result suggests that processed MMG signals indicate muscle fatigue and can, thus, be used as the feedback in FES systems.

The Paralympic boccia is a sport played by athletes with spasticity and severe impairment in the four limbs. Three (BC1, BC2, and BC3) of the four classes in boccia allow People with Cerebral Palsy (CP) to participate. The ranking is performed manually through the American Spasticity Scale. Like all qualitative scales, however, this evokes controversy among the evaluation board members who apply it, altering the classification of the athletes. A helpful option would be the use of mechanomyography (MMG), a method of acquiring muscle vibrations quantitatively based on accelerometers. Thus, the objective of this article was to conduct a pilot study analyzing the differences in the MMG signals of flexors and extensors muscles between two groups: 6 boccia athletes with spasticity and 6 non-impaired. Volunteers remained seated on the wheelchair, with their elbow bent close to 90°. They were verbally stimulated to perform the manual grip by pressing the evaluator’s hand while the MMG signals were recorded and stored. The mean MMGRMS descriptor was calculated for each signal. The experimental tests indicated differences between the two groups. For the spasticity group: 0.4058 and 0.4258 mV for the left flexor and extensor wrist muscles, respectively; 0.4215 and 0.4529 mV for the right flexor and extensor wrist muscles, respectively. For the non-impaired group, the MMGRMS was 0.3694 and 0.3945 mV for the left flexor and extensor wrist muscles, respectively; 0.35033 and 0.3728 mV for the right flexor and extensor wrist muscles, respectively. Thus, these results indicate greater spasticity for the spastic group and so, volunteers classification in lower levels.

This work proposes the classification of motor imagery signals for brain-machine interfaces with functional electrical stimulation in the quadriceps muscle. Five volunteers participated in the test, 3 healthy participants, aged 28 ± 3 years, and 2 paraplegic volunteers, aged 43 (ASIA-B, C7 level - 16 years) and 47 (ASIA-A, T7 level - 20 years) years respectively. In total, each participant performed 90 repetitions of motor imaging of the lower limb under electrical stimulation, with frequencies of 20Hz, 35Hz, and 50Hz and current amplitude of 20mA. The patterns were analyzed off-line and submitted to the classification architectures after application of spatial filtering to extract the characteristics. The classification of the patterns was performed using the architectures: (i) Linear Discriminant Analysis (LDA), (ii) Multilayer Perceptron (MLP), and (iii) Support Vector Machine (SVM). To validate the proposal, the performance was compared between the classifiers through the accuracy of cross validation, variance, precision, and sensitivity. With the SVM classifier, the best accuracy percentage was 86.5%. These results are promising and the trained architectures are feasible for implementation in neuroprostheses with lower computational resources.

The use of neuromuscular electrical stimulation (NMES) to artificially restore movement in people with complete spinal cord injury (SCI) induces an accelerated process of muscle fatigue. Fatigue increases the time between the beginning of NMES and the onset of muscle force (DelayTOT ). Understanding how much muscle fatigue affects the DelayTOT in people with SCI could help in the design of closed-loop neuroprostheses that compensate for this delay, thus making the control system more stable. The aim of this study was to evaluate the impact of the extent of fatigue on DelayTOT and peak force of the lower limbs in people with complete SCI. Fifteen men-young adults with complete SCI (paraplegia and tetraplegia) and stable health-participated in the experiment. DelayTOT was defined as the time interval between the beginning of NMES application until the onset of muscle force. The electrical intensity of NMES applied was adjusted individually and consisted of the amplitude required to obtain a full extension of the knee (0°), considering the maximum electrically stimulated extension (MESE). Subsequently, 70% of the MESE was applied during the fatigue induction protocol. Significant differences were identified between the moments before and after the fatigue protocol, both for peak force (P ≤ .026) and DelayTOT (P ≤ .001). The medians and interquartile range of the DelayTOT were higher in postfatigue (199.0 ms) when compared to the moment before fatigue (146.5 ms). The medians and interquartile range of the peak force were higher in unfatigued lower limbs (0.43 kgf) when compared to the moment postfatigue (0.27 kgf). The results support the hypothesis that muscle fatigue influences the increase in DelayTOT and decrease in force production in people with SCI. For future applications, the combined evaluation of the delay and force in SCI patients provides valuable feedback for NMES paradigms. The study will provide potentially critical muscle mechanical evidence for the investigation of the evolution of atrophy.

O objetivo do presente estudo é relatar sobre a importância do programa complementar de ensino “Subsídios anatômicos para a clínica cirúrgica” ao estudante de Medicina. Os dados apresentados foram coletados entre os anos de 2006 a 2016. Neste período foram inscritos 339 graduandos do curso de Medicina e as áreas da clínica cirúrgica contempladas no programa foram: cirurgias de cabeça e pescoço, ortopédicas e oncológicas (mastectomia e prostatectomia), além de biópsias. Em linhas gerais, concluiu-se que as atividades desenvolvidas neste programa de ensino cumpriram seu propósito baseado nas experiências vivenciadas pelos estudantes e docentes à medida que incrementaram os conhecimentos básicos e indispensáveis da Anatomia para o exercício da vida profissional da área médica. Também instigou os acadêmicos participantes a elaborar pesquisas que contribuam para a criação de novas técnicas de abordagem cirúrgica.

Introduction This study aims to assess the influence of different skinfold thicknesses (ST) and their relation to the attenuation of the mechanomyographic (MMG) signal at different force levels (maximal voluntary contraction – MVC, 40% of MVC and 70% of MVC) of the rectus femoris muscle. Methods Fifteen volunteers were divided in two groups: ST lower than 10mm (G35) (7 participants). Student t tests were employed to investigate differences between G35 regarding MMG analysis parameters (acceleration root mean square – aRMS, zero crossing – ZC, and median frequency – MDF), for the X, Y and Z axes, as well as for the modulus of these three axes. Results We found that thicker layers of body fat act as attenuator filters for the MMG signal [MDFMVC: X (p = 0.005), Z (p = 0.003); MDF70%MVC: X (p = 0.034); ZCMVC: Z (p = 0.037), modulus (p = 0.005); ZC70%MVC: Z (p = 0.047)]. We found significant correlation between ST values and aRMS in three levels, in the Yaxis (p = 0.591), for the group G35 in 40%MVC (R2 = 0.610), and 70%MVC (R2 = 0.592). The MDF parameter showed correlation with ST values only in the Yaxis in 70%MVC (R2 = 0.700) for G>35. Conclusions We observed MMG signal attenuation in at least one of the parameters analyzed for each level of the rectus femoris muscle force, indicating that MMG signals are significantly attenuated with increasing thickness of the subcutaneous fat layer.

Background The mechanisms underlying impaired balance in chronic obstructive pulmonary disease (COPD) are poorly understood, which makes it difficult to choose the best therapeutic approaches. Therefore, this study aimed to investigate patterns of muscular activation to maintain balance and its determinants in this population. Methods Thirty-three subjects with COPD and 33 controls were assessed by a force platform in four tasks: standing with eyes opened (FHEO) and closed (FHEC); standing on unstable surface (SUS) and one-legged stance (OLS). Electromyographic activity of lower limb, trunk and neck muscles was concomitantly recorded. To asses functional balance, Brief-balance evaluation systems and timed up & go (TUG) tests were applied. Lung function, exercise capacity and muscle force were also assessed. Results Subjects with COPD presented worse balance and higher scalene activation than controls in OLS (mean difference 23.0 [95%CI 1.7–44.3] %Δ μVRMS; P = 0.034), besides presenting also higher activation of gluteus medius during FHEC task (mean difference 1.5 [95%CI 0.2–2.8] %Δ μVRMS; P = 0.023) and taking longer to complete the TUG (mean difference 0.6 [95%CI 0.1–1.2] seconds; P = 0.042). Exercise capacity and peripheral muscle force were determinants of functional balance (r2 = 0.505), whereas age (OR = 1.24; 95%CI 1.02–1.52) and total lung capacity (OR = 2.42; 95%CI 1.05–5.56) were determinants of static balance. Conclusion Individuals with COPD have worse static and functional balance in comparison with controls, besides presenting higher activation of scalene and gluteus medius during static balance tasks. Exercise capacity and peripheral muscle force emerged as determinants of functional balance, whereas age and lung hyperinflation contributed to poor static balance.

The application of low-intensity electrical stimulation (LIES) to neural tissue increases neurochemical factors responsible for regeneration as nerve growth factor. Stem cell (SC) therapy for patients with Spinal cord injury (SCI) promote some increase functional improvement.ObjectiveInvestigate the electromyographic response in paraplegic dogs undergoing LIES and SC transplantation.Methods27 dogs paraplegics with SCI were divided into three groups with different types of therapy. GADSC: two SC transplants (n = 9); GLIES: LIES (n = 8); GCOMB: two SC transplants and LIES (n = 10). Adipose derived mesenchymal stem cells (ADSCs) were transplanted by lumbar puncture in the amount of 1.2 × 106 cells/50 μL. Acupuncture needles positioned in the interspinous space were used for stimulation. The electrical stimulation was applied with a mean voltage ∼30 mV and four consecutive modulated frequencies (5 Hz, 10 Hz, 15 Hz and 20 Hz) within 5 min each. The patients motor performance was evaluated before (Pre) the procedure and after 30 (Post30) and 60 (Post60) days, from electromyography root mean square (EMGRMS) registered with subcutaneous electrodes in the vastus lateralis muscle, while the animals were in quadrupedal position.ResultsAll three groups showed a significant intra-group increase of EMGRMS (Pre vs. Post30 or Pre vs. Post60). However, there were no statistically significant differences between Post30 and Post60. The inter-group test (GADSC X GLIES X GCOMB) did not present significance when compared the instants Pre (p = 0.34), Post30 (p = 0.78) and Post60 (p = 0.64).ConclusionSome dogs recovered motor activity, expressed by the EMGRMS, in all groups, in pre vs. post (30 or 60 days) comparisons. This is the peer-reviewed version of the article: Krueger, E., Magri, L.M.S., Botelho, A.S., Bach, F.S., Rebellato, C.L.K., Fracaro, L., Fragoso, F.Y.I., Villanova, J.A., Brofman, P.R.S., Popović-Maneski, L., 2019. Effects of low-intensity electrical stimulation and adipose derived stem cells transplantation on the time-domain analysis-based electromyographic signals in dogs with SCI. Neuroscience Letters 696, 38–45. [https://doi.org/10.1016/j.neulet.2018.12.004] Published version: [https://hdl.handle.net/21.15107/rcub_dais_4595]

The muscle-machine interface assists in the neuroplasticity of healthy with lesions during the combination of electromyography techniques and functional electrical stimulation (EMG-FES). This case report aimed to evaluate this interface for rehabilitation in a post-stroke participant. For the treatment, an EMG-FES interface was associated with functional exercises for wrist and finger extension. This case report aimed to evaluate this interface for rehabilitation in a post-stroke participant. The protocol was applied 3x/week during 12 sessions. Were applied eliminatory tests (Mini mental exam, active range of motion and Ashworth modified scale), functional tests (Fugl Meyer scale and 9 hole peg test) and electromyography evaluation in time (EMGRMS) and frequency (EMGMDF) domain. In the functional tests occurred increase in sensibility, mobility, oriented tasks and pain reduction (18/48 to 23/48) and the electromyography showed an increase 35.12 VRMS in EMGRMS and 123 Hz in EMGMDF. This interface is effective for improving voluntary movement of hand extension after stroke.

Aims: This study tested whether performing exergames with and without additional external load could induce to different internal load demand for young adults. Methods: Fifteen young women (24.4 ± 4.06 years) participated in the study. Electromyography (EMG) activity, heart rate (HR) and overall and local rating of perceived exertion (RPE) were determined in “Just Dance” and “Ski” exergames without additional external load and with additional external load of 5% of body mass attached bilaterally to the ankles in “Just Dance” and using a weight vest in “Ski”. Results: EMG, HR and overall RPE presented similar responses between loads in both exergames (p>.05). However, local RPE differentiate internal load only in “Just Dance”, with higher values with additional load (with additional load: 11.2 ± 2.1 RPE; without additional load: 10.3 ± 1.4 RPE; p = .037). Conclusion: Therefore, performing exergames with an additional external load of 5% of young women body mass did not induce different internal load demand in “Just Dance” and “Ski” exergames compared to performing such games without external load. However, the greater local RPE in “Just Dance” exergame after adding the external load suggests that a higher amount of load (i.e., > 5% of body mass) to this population may generate different internal load demand.

Neuromuscular electrical stimulation (NMES) is a common tool that is used in clinical and laboratory experiments and can be combined with mechanomyography (MMG) for biofeedback in neuroprostheses. However, it is not clear if the electrical current applied to neuromuscular tissues influences the MMG signal in submaximal contractions. The objective of this study is to investigate whether the electrical stimulation frequency influences the mechanomyographic frequency response of the rectus femoris muscle during submaximal contractions. Thirteen male participants performed three maximal voluntary isometric contractions (MVIC) recorded in isometric conditions to determine the maximal force of knee extensors. This was followed by the application of nine modulated NMES frequencies (20, 25, 30, 35, 40, 45, 50, 75, and 100 Hz) to evoke 5% MVIC. Muscle behavior was monitored by the analysis of MMG signals, which were decomposed into frequency bands by using a Cauchy wavelet transform. For each applied electrical stimulus frequency, the mean MMG spectral/frequency response was estimated for each axis (X, Y, and Z axes) of the MMG sensor with the values of the frequency bands used as weights (weighted mean). Only with respect to the Z (perpendicular) axis of the MMG signal, the stimulus frequency of 20 Hz did not exhibit any difference with the weighted mean (P = 0.666). For the frequencies of 20 and 25 Hz, the MMG signal displayed the bands between 12 and 16 Hz in the three axes (P 0.050). In the frequencies from 30 to 100 Hz, the muscle presented a higher concentration of the MMG signal between the 22 and 29 Hz bands for the X and Z axes, and between 16 and 34 Hz bands for the Y axis (P 0.050 for all cases). We observed that MMG signals are not dependent on the applied NMES frequency, because their frequency contents tend to mainly remain between the 20- and 25-Hz bands. Hence, NMES does not interfere with the use of MMG in neuroprosthesis.

The modified Ashworth scale (MAS) is the most widely used measurement technique to assess levels of spasticity. In MAS, the evaluator graduates spasticity considering his/her subjective analysis of the muscular endurance during passive stretching. Therefore, it is a subjective scale. Mechanomyography (MMG) allows registering the vibrations generated by muscle contraction and stretching events that propagate through the tissue until the surface of the skin. With this in mind, this study aimed to investigate possible correlations between MMG signal and muscle spasticity levels determined by MAS. We evaluated 34 limbs considered spastic by MAS, including upper and lower limbs of 22 individuals of both sexes. Simultaneously, the MMG signals of the spastic muscle group (agonists) were acquired. The features investigated involved, in the time domain, the median energy (MMGME) of the MMG Z-axis (perpendicular to the muscle fibers) and, in the frequency domain, the median frequency (MMG mf ). The Kruskal-Wallis test (p me . There was a high linear correlation between the MMG me and MAS (R2=0.9557) and also a high correlation as indicated by Spearman test (ρ=0.9856; p mf did not present significant differences between MAS spasticity levels. There was moderate linear correlation between MAS and MMG mf (R2=0.4883 and Spearman test [ρ = 0.4590; p < 0.001]). Between the two investigated features, we conclude that the median energy is the most viable feature to evaluate spasticity due to strong correlations with the MAS.