Performance, reliability and fatigue in prone bridge test and supine unilateral bridge test.

INTRODUCTION: 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. METHODS: 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. RESULTS: 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 (ICC >0.836; 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. CONCLUSION: 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.

Punctual mechanical oscillation in modulation of muscular tonus in children with spasticity

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.

Are there differences in muscular activation to maintain balance between individuals with chronic obstructive pulmonary disease and controls?

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.

A utilização do código de quick response no ensino da anatomia humana do aparelho locomotor / The use of quick response code in teaching musculoskeletal anatomy

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.

The study of human anatomy is a relevant part of the curriculum of health course graduation students. Given the constant reduction of hours destinated to the study of Anatomy and the debates regarding new teaching methods, the use of the Quick Response Code (QR code) has shown to be promising. Therefore, the Anatomy Department at the State University of Londrina (UEL) has developed a cataloging process concerning anatomical structures with the application of QR code, and this paper has the purpose of reporting on such experience. In the process, the structures dissected in UEL's Anatomy Laboratory were cataloged based on a spreadsheet which contained the correlation between these structures and numbers; the information regarding each structure was then transcribed into a QR code using a digital generator, with posterior printing, lamination and attachment to the body part. The labels were made by sewing the numbered tags onto the structures. Within the discussion regarding alternative teaching methods, examples can be given regarding lamination, three-dimension projection and prospection. The use of the QR code has proven to be a valid alternative in aggregating knowledge to academic curriculum. Through the activities performed in the process of cataloging, it was possible not only to dedicate more time to the theorical and practical learning of human anatomy, but also to increase the independence in studying and developing research. Furthermore, there is an opportunity to expand the analysis directed toward human anatomy teaching and toward new learning methods.

Fatigue in complete spinal cord injury and implications on total delay.

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.

Anatomia humana na clínica cirúrgica: programa de formação complementar no ensino da medicina / Human anatomy surgical clinic: complementary training program in medicine teaching

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.

The aim of this study is to report the importance of the complementary training program referred to as "Anatomical subsidies for surgical clinic" provided to medical students. The data were collected between 2006 and 2016. During that period, a total of 339 students from the Medicine course were registered, and the surgery clinical areas covered in the program included: head and neck surgery, orthopedic surgery and oncology (breast cancer and prostatectomy) surgery, as well as biopsies. In general, it could be noted that the activities developed in the teaching program fulfilled the purpose based on the experiences of the students and professors, increasing the basic and indispensable knowledge of anatomy to the professional life of a clinical doctor or surgeon. It also instigated the participating students to produce research that will further contribute to the creation of new techniques related to surgical approaches.

Reduction in knee pain symptoms in athletes using an acupuncture protocol / Redução da sintomatologia dolorosa de joelho em atletas utilizando protocolo de acupuntura

ABSTRACT Pain in the lower limbs is common in athletes and a limiting factor in performance. Acupuncture has shown positive effects as an analgesic treatment and may potentially be used for pain reduction in runners. This study aimed to analyze the parameters associated with knee pain by correlating strength parameters of the musculature assessed in runners treated with acupuncture. A descriptive longitudinal study was conducted on 34 runners of both sexes aged 20 to 52 years, who presented with knee-related pain from January to June, 2015. Two pain questionnaires and a maximal strength test with electromyographic evaluation of the rectus femoris, vastus lateralis, and medialis muscles were used, and patients were monitored during five follow-up visits after an acupuncture protocol. All participants reported experiencing a decrease in knee pain after treatment. The affected limbs showed an increase in average strength by 34% and 25% compared to the contralateral limb. An increase in the number of motor units recruited for the three muscles was observed in both limbs. In conclusion, the proposed acupuncture protocol was effective in reducing pain symptoms in the knee region of athletes, thus influencing their gain in strength and muscle balance. Level of Evidence IV, Case series.

RESUMO A dor em membros inferiores é comum em atletas e representa um aspecto limitante ao rendimento. Buscando atenuação para a dor desta população, utiliza-se a acupuntura por apresentar bons efeitos na analgesia. Objetivo: analisar os parâmetros relacionados à dor de joelho correlacionando os parâmetros de força das musculaturas avaliadas em corredores submetidos a tratamento de acupuntura. Métodos: Foi realizado um estudo longitudinal, de janeiro a junho de 2015, com 34 corredores de 20 a 52 anos de ambos os sexos, que apresentassem dor de joelho. Foram aplicados dois questionários de dor e um teste de força máxima com avaliação eletromiográfica dos músculos reto femoral, vasto lateral e medial, com cinco atendimentos seguindo um protocolo de acupuntura. Resultados: Todos os voluntários relataram diminuição da dor de joelho após o tratamento. A média de força do membro afetado teve incremento de 34% e do membro contralateral de 25%. Verificou-se aumento no número de recrutamento de unidades motoras para os três músculos avaliados em ambos os membros. Conclusão: O protocolo proposto se mostrou eficaz na diminuição da sintomatologia dolorosa na região de joelhos de atletas corredores, interferindo no ganho de força e no equilíbrio muscular. Nível de Evidência IV, Série de casos.

Investigation of the Relationship Between Electrical Stimulation Frequency and Muscle Frequency Response Under Submaximal Contractions.

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.

Mechanomyography-Based Wearable Monitor of Quasi-Isometric Muscle Fatigue for Motor Neural Prostheses.

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.

REDUCTION IN KNEE PAIN SYMPTOMS IN ATHLETES USING AN ACUPUNCTURE PROTOCOL.

Pain in the lower limbs is common in athletes and a limiting factor in performance. Acupuncture has shown positive effects as an analgesic treatment and may potentially be used for pain reduction in runners. This study aimed to analyze the parameters associated with knee pain by correlating strength parameters of the musculature assessed in runners treated with acupuncture. A descriptive longitudinal study was conducted on 34 runners of both sexes aged 20 to 52 years, who presented with knee-related pain from January to June, 2015. Two pain questionnaires and a maximal strength test with electromyographic evaluation of the rectus femoris, vastus lateralis, and medialis muscles were used, and patients were monitored during five follow-up visits after an acupuncture protocol. All participants reported experiencing a decrease in knee pain after treatment. The affected limbs showed an increase in average strength by 34% and 25% compared to the contralateral limb. An increase in the number of motor units recruited for the three muscles was observed in both limbs. In conclusion, the proposed acupuncture protocol was effective in reducing pain symptoms in the knee region of athletes, thus influencing their gain in strength and muscle balance. Level of Evidence IV, Case series.

A dor em membros inferiores é comum em atletas e representa um aspecto limitante ao rendimento. Buscando atenuação para a dor desta população, utiliza-se a acupuntura por apresentar bons efeitos na analgesia. Objetivo: analisar os parâmetros relacionados à dor de joelho correlacionando os parâmetros de força das musculaturas avaliadas em corredores submetidos a tratamento de acupuntura. Métodos: Foi realizado um estudo longitudinal, de janeiro a junho de 2015, com 34 corredores de 20 a 52 anos de ambos os sexos, que apresentassem dor de joelho. Foram aplicados dois questionários de dor e um teste de força máxima com avaliação eletromiográfica dos músculos reto femoral, vasto lateral e medial, com cinco atendimentos seguindo um protocolo de acupuntura. Resultados: Todos os voluntários relataram diminuição da dor de joelho após o tratamento. A média de força do membro afetado teve incremento de 34% e do membro contralateral de 25%. Verificou-se aumento no número de recrutamento de unidades motoras para os três músculos avaliados em ambos os membros. Conclusão: O protocolo proposto se mostrou eficaz na diminuição da sintomatologia dolorosa na região de joelhos de atletas corredores, interferindo no ganho de força e no equilíbrio muscular. Nível de Evidência IV, Série de casos.

Effects of additional external load manipulation on perceptual and physiological responses during exergame

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.(AU)

Electromyographic analysis of postural overload caused by bulletproof vests on public security professionals

Abstract 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.

Influence of subcutaneous fat on mechanomyographic signals at three levels of voluntary effort

Abstract 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 (G<10) (8 participants) and ST higher than 35mm (G>35) (7 participants). Student t tests were employed to investigate differences between G<10 and G>35 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 G<10. For the modulus, the aRMS value showed correlation with ST values for group G>35 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.

Artificial motor control for electrically stimulated upper limbs of plegic or paretic people

Introduction: Functional Electrical Stimulation (FES) is a technique used in the restoration and generation of movements performed by subjects with neuromuscular disorders such as spinal cord injury (SCI). The purpose of this article is to outline the state of the art and perspectives of the use of FES in artificial motor control of the upper limbs in paretic or plegic people. Methods The databases used in papers selection were Google Scholar and Capes’ Portals as well as proceedings of the Annual Conference of the International Functional Electrical Stimulation Society (IFESS). Results Approximately 85% of the reviewed studies showed FES profile with pulse duration ranging from 1 to 300 μs and modulating (burst) frequency between 10 and 40 Hz. Regarding the type of electrodes, 88% of the studies employed transcutaneous electrodes. Conclusion We concluded that FES with closed-loop feedback and feedforward are the most used and most viable systems for upper limbs motor control, because they perform self-corrections slowing neuromuscular adaptation, allowing different planes and more range of movement and sensory-motor integration. One of the difficulties found in neuroprosthesis systems are electrical wires attached to the user, becoming uninteresting in relation to aesthetics and break. The future perspectives lead to a trend to miniaturization of the stimulation equipment and the availability of wireless networks, which allow the attachment of modules to other components without physical contact, and will become more attractive for daily use.

Correlation between spectral and temporal mechanomyography features during functional electrical stimulation

Abstract Introduction: Signal analysis involves time and/or frequency domains, and correlations are described in the literature for voluntary contractions. However, there are few studies about those correlations using mechanomyography (MMG) response during functional electrical stimulation (FES) elicited contractions in spinal cord injured subjects. This study aimed to determine the correlation between spectral and temporal MMG features during FES application to healthy (HV) and spinal cord injured volunteers (SCIV). Methods: Twenty volunteers participated in the research divided in two groups: HV (N=10) and SCIV (N=10). The protocol consisted of four FES profiles transcutaneously applied to quadriceps femoris muscle via femoral nerve. Each application produced a sustained knee extension greater than 65º up to 2 min without adjusting FES intensity. The investigation involved the correlation between MMG signal root mean square (RMS) and mean frequency (MF). Results: HV and SCIV indicated that MMGRMS and MMGMF variations were inversely related with -0.12 ≥ r ≥ -0.82. The dispersion between MMGMF and MMGRMS reached 0.50 ≤ r2 ≤ 0.64. Conclusion The increase in MMGRMS and the decrease in MMGMF may be explained by the motor units coherence during fatigue state or by motor neuron adaptation (habituation) along FES application (without modification on parameters).

Lung analysis in children mechanically ventilated with atelectasis after cardiac surgery / Análise pulmonar em crianças mecanicamente ventiladas com atelectasia após cirurgia cardíaca / Análisis pulmonar en niños mecánicamente ventilados con atelectasia después de cirugía cardiaca

ABSTRACT The main objective of this study is to associate the healthy area of the lung (evaluated by radiography) with the data of respiratory mechanics in children with atelectasis after cardiac surgery, under mechanical ventilation in the assisted controlled mode. Altogether, 46 children were selected, but 16 were excluded due to irregular respiratory waves or lack of the data on arterial blood gases. A group of 30 children under assisted controlled mode were analyzed, and 10 from this group developed atelectasis. The data were analyzed before and after the onset of atelectasis, and respiratory mechanics was correlated to radiography. We also analyzed the data related to arterial blood gas of these children - who initially had no pulmonary complication - to verify possible changes due to assisted controlled cycles. Atelectasis may modify some parameters of respiratory mechanics. In the association of the healthy area of the lung with the respiratory mechanics, the Spearman correlation results showed statistical significance of the lung area with airway resistance (ρ=−0.648 and p=0.043). Our results show that it is possible to analyze respiratory mechanics waves by selecting controlled cycles in the assisted controlled mode, since we found insignificant changes in potential ionic hydrogen. The analysis of respiratory mechanics allows checking lung function and undesired lung injuries; the analysis of respiratory mechanics can be daily performed in these children to have important information on the pulmonary function. Our research also showed that under the assisted controlled mode is also possible to evaluate respiratory mechanics.

RESUMO O objetivo deste estudo é associar a área saudável do pulmão (avaliada pela radiografia) aos dados de mecânica respiratória em crianças no pós-operatório de cirurgia cardíaca, com atelectasia em ventilação mecânica no modo assistido controlado. No total, foram selecionadas 46 crianças, das quais 16 foram excluídas devido às ondas respiratórias irregulares ou à falta de dados da gasometria arterial. Foi analisado um grupo de 30 crianças em modo assistido controlado, sendo que 10 crianças desenvolveram atelectasia. Os dados foram analisados antes e após o início da atelectasia, e a mecânica respiratória foi correlacionada às medidas da área do pulmão. Nas 30 crianças, inicialmente sem complicação pulmonar, foram analisados os dados da gasometria arterial para verificar possíveis mudanças devido aos ciclos assistidos. A atelectasia pode modificar alguns parâmetros da mecânica respiratória. Na associação da área saudável do pulmão com a mecânica respiratória, os resultados da correlação de Spearman mostraram significância estatística entre a área do pulmão com a resistência das vias aéreas (ρ=-0,648 e p=0,043). Os resultados demonstraram que é possível a análise das ondas de mecânica respiratória através da seleção dos ciclos controlados, uma vez que não houve alteração significativa no potencial de hidrogênio iônico. A análise da mecânica respiratória permite verificar a função pulmonar e as possíveis lesões pulmonares. A análise da mecânica respiratória pode ser usada diariamente nessas crianças, permitindo obter informações importantes da função pulmonar. O estudo também mostrou que no modo ventilatório assistido controlado também é possível avaliar a mecânica respiratória.

RESUMEN El objetivo de este estudio es asociar la área sana del pulmón (evaluado mediante radiografía) a los datos de mecánica respiratoria en niños en el postoperatorio de cirugía cardiaca, con atelectasia en ventilación mecánica en el modo asistido controlado. En el total, fueron seleccionados 46 niños, de los cuales 16 fueron excluidos debido a las ondas respiratorias irregulares o a la falta de datos de la gasometria arterial. Se analizó un grupo de 30 niños en el modo asistido controlado, de los cuales 10 han desarrollado atelectasia. Los datos fueron analizados antes y después del inicio de la atelectasia, y la mecánica respiratoria se correlacionó a las medidas del área del pulmón. En los 30 niños inicialmente sin complicación pulmonar fueron analizados los datos de la gasometria arterial para comprobar posibles cambios debido a los ciclos asistidos. La atelectasia puede modificar algunos parámetros de la mecánica respiratoria. En la asociación del área saludable del pulmón con la mecánica respiratoria, los resultados de correlación de Spearman demostraron significancia estadística entre el área del pulmón con la resistencia de las vías aéreas (ρ=-0,648 y p=0,043). Los resultados mostraron que es posible el análisis de las ondas de mecánica respiratoria a través de la selección de los ciclos controlados, puesto que no hubo alteración significativa en el potencial de hidrógeno iónico. El análisis de la mecánica respiratoria permite comprobar la función pulmonar y las posibles lesiones pulmonares. Es posible utilizar el análisis de la mecánica respiratoria diariamente en estos niños, permitiendo obtener informaciones importantes de la función pulmonar. El estudio también mostró que en el modo de ventilación controlada es posible evaluar la mecánica respiratoria.

Advances and perspectives of mechanomyography

INTRODUCTION: The evaluation of muscular tissue condition can be accomplished with mechanomyography (MMG), a technique that registers intramuscular mechanical waves produced during a fiber's contraction and stretching that are sensed or interfaced on the skin surface. OBJECTIVE: Considering the scope of MMG measurements and recent advances involving the technique, the goal of this paper is to discuss mechanomyography updates and discuss its applications and potential future applications. METHODS: Forty-three MMG studies were published between the years of 1987 and 2013. RESULTS: MMG sensors are developed with different technologies such as condenser microphones, accelerometers, laser-based instruments, etc. Experimental protocols that are described in scientific publications typically investigated the condition of the vastus lateralis muscle and used sensors built with accelerometers, third and fourth order Butterworth filters, 5-100Hz frequency bandpass, signal analysis using Root Mean Square (RMS) (temporal), Median Frequency (MDF) and Mean Power Frequency (MPF) (spectral) features, with epochs of 1 s. CONCLUSION: Mechanomyographic responses obtained in isometric contractions differ from those observed during dynamic contractions in both passive and functional electrical stimulation evoked movements. In the near future, MMG features applied to biofeedback closed-loop systems will help people with disabilities, such as spinal cord injury or limb amputation because they may improve both neural and myoelectric prosthetic control. Muscular tissue assessment is a new application area enabled by MMG; it can be useful in evaluating the muscular tonus in anesthetic blockade or in pathologies such as myotonic dystrophy, chronic obstructive pulmonary disease, and disorders including dysphagia, myalgia and spastic hypertonia. New research becomes necessary to improve the efficiency of MMG systems and increase their application in rehabilitation, clinical and other health areas.

Iontophoresis: principles and applications / Iontoforese: princípios e aplicações

Introduction Iontophoresis is a noninvasive technique used to increase transdermal penetration of substances through the skin layer (epidermis, dermis and hypodermis) in a controlled manner. Technological advance in recent decades have provided reduced cost of equipment needed for implementation, which allowed for the expansion of this technique. Objective The aim of this paper is to present the state of the art on iontophoresis, ranging from the atomic characteristics of the ion formation to the current applications of the technique. Methods Were researched papers from databases: IOP publishing, ScienceDirect, Pubmed, Springer, IEEE Xplore, Google Scholar and books with keywords iontophoresis, ions, topical applications between 1967 and 2010. Results Were selected (number of papers and database) 1 IOP Publishing, 1 from ScienceDirect, Central, 1 from Springer, 2 from PubMed, 11 from IEEE Xplore, 35 from Google Scholar, and 15 books, totaling 66 references and websites with nationally marketed electrotherapy products. Conclusion Iontophoresis is suitable for applications such as acetic acid (calcific tendinitis and myositis ossificans), calcium chloride and magnesium sulfate (control of musculoskeletal spasms), dexamethasone (inflammation), lidocaine (inflammation of soft tissues), zinc oxide (rheumatoid arthritis). It is also used in cosmetic applications with devices attached to the skin and for eye treatment aimed at specific tissues of the eye, providing a treatment option for various eye diseases, reducing the complications secondary to traditional methods of treatment. The advantages are the significant increase in the release and control of therapeutic agents, including drugs with high molecular weight. The disadvantages of iontophoresis are the complexity of the drug release system and prolonged exposure of the skin to an electrical current. .

Introdução A iontoforese é uma técnica não invasiva utilizada para aumentar, de forma controlada, a penetração transdermal de substâncias através das camadas da pele (epiderme, derme e hipoderme). O avanço tecnológico nas últimas décadas proporcionou uma redução no custo dos equipamentos necessários à sua aplicação, o que possibilitou a expansão dessa técnica. Objetivo Apresentar o estado da arte sobre iontoforese, abrangendo desde as características atômicas da formação do íon até as atuais aplicações da técnica. Métodos Foram pesquisados artigos das bases de pesquisa: IOP publishing, ScienceDirect, Pubmed, Springer, IEEE Xplore, Google Scholar e livros com os unitermos: iontophoresis, ions, topical applications entre os anos de 1967 e 2010. Resultados Foram selecionados (número de artigos e base de pesquisa) 1 da IOP Publishing, 1 da ScienceDirect, 1 da Springer, 2 da PubMed, 11 da IEEE Xplore, 35 do Google Scholar e 15 livros, totalizando 66 referências, além de websites com produtos comerciais nacionais de eletroterapia. Conclusão A iontoforese é indicada para aplicações como de ácido acético (tendinite calcificante e miosite ossificante), cloreto de cálcio e sulfato de magnésio (controle de espasmos musculoesqueléticos), dexametasona (inflamação), lidocaína (inflamação de tecidos moles), óxido de zinco (artrite reumatóide). Também é utilizada em aplicações cosméticas com dispositivos aderidos à pele e em tratamento ocular visando tecidos específicos do olho, oferecendo uma forma de tratamento para diversas doenças oculares, diminuindo as complicações apresentadas em métodos clássicos de tratamento. As vantagens ...

Mechanomyography energy decreases during muscular fatigue in paraplegics.

The present work investigated the response of triaxial MMG signals acquired from the rectus femoris muscle of spinal cord injured volunteers during fatigue protocol electrically evoked. A custom functional electrical stimulator voltage-controlled was configured as: pulse frequency set to 1 kHz (20% duty cycle) and burst (modulating) frequency set to 70 Hz (20% active period). The triaxial MMG signal of rectus femoris muscle was processed with third-order 5-50 Hz bandpass Butterworth filter and the values were normalized. A load cell was used to register the force. The stimulator output voltage was increased until the maximal electrically-evoked extension (MEEE) of knee joint. After the load cell placement, the stimuli magnitude required to reach the MEEE was applied and registered by the load cell as muscular force-100% response. Stimuli intensity was increased until and during the control to keep the force in force-100%. Four instants with force functional electrical stimulation (FES)-controlled were selected between force-100% and slope down to force-30%. The MMG energy decreased with FES application due neuromuscular fatigue in paraplegic subjects. X-axis between instant I (1 ± 0) and instant IV (0.74 ± 0.27), and the same tendency was found to Y-axis between instant II (1.14 ± 0.44) and instant IV (0.91 ± 0.3).

Relationship between peak and mean amplitudes of the stimulating output voltage for functional control of the knee by spinal cord patients and healthy volunteers

INTRODUCTION: Functional electrical stimulation (FES) may evoke movements in people with movement impairments due to neurological lesion. The mean value of electrical current or voltage during FES depends on the stimulatory profile parameters. To investigate the relationship between peak and mean amplitudes of the stimulator output voltage while causing a knee extension angle change from 90º to 40º to choose the best and safest profile to be applied in people who have suffered a spinal cord injury. METHODS: Healthy (N = 10) volunteers and those with spinal cord injuries (N = 10) participated in this study. Each FES profile (P1, P2, P3 and P4) had 1-kHz pulses (100 µs or 200 µs on and 900 µs or 800 µs off) with burst frequencies of 50 Hz (3 ms on and 17 ms off) or 70 Hz (3 ms on and 11 ms off) and peak amplitudes set between 53-125V for healthy volunteers and 68-198 V for volunteers with spinal cord injury. RESULTS: The highest mean amplitude were obtained using a FES profile with active/total pulse period of 200 us/1000 us and burst frequency of 3ms/14ms. The best results of mean amplitude were observed using a FES profile duty cycle of 10% for pulses (100 µs/1000 µs) and 15% for bursts (3 ms/20 ms). CONCLUSION: The FES profile (100 µs - 50 Hz) seems to be the most suitable for both groups, inasmuch as it presents smaller mean amplitudes and peak amplitudes similar to other FES profiles.