Stroke survivors often face significant challenges when performing daily self-care activities due to upper limb motor impairments.Traditional surface electromyography(sEMG)analysis typically focuses on isolated hand p...Stroke survivors often face significant challenges when performing daily self-care activities due to upper limb motor impairments.Traditional surface electromyography(sEMG)analysis typically focuses on isolated hand postures,overlooking the complexity of object-interactive behaviors that are crucial for promoting patient independence.This study introduces a novel framework that combines high-density sEMG(HD-sEMG)signals with an improved Whale Optimization Algorithm(IWOA)-optimized Long Short-Term Memory(LSTM)network to address this limitation.The key contributions of this work include:(1)the creation of a specialized HD-sEMG dataset that captures nine continuous self-care behaviors,along with time and posture markers,to better reflect real-world patient interactions;(2)the development of a multi-channel feature fusion module based on Pascal’s theorem,which enables efficient signal segmentation and spatial–temporal feature extraction;and(3)the enhancement of the IWOA algorithm,which integrates optimal point set initialization,a diversity-driven pooling mechanism,and cosine-based differential evolution to optimize LSTM hyperparameters,thereby improving convergence and global search capabilities.Experimental results demonstrate superior performance,achieving 99.58%accuracy in self-care behavior recognition and 86.19%accuracy for 17 continuous gestures on the Ninapro db2 benchmark.The framework operates with low latency,meeting the real-time requirements for assistive devices.By enabling precise,context-aware recognition of daily activities,this work advances personalized rehabilitation technologies,empowering stroke patients to regain autonomy in self-care tasks.The proposed methodology offers a robust,scalable solution for clinical applications,bridging the gap between laboratory-based gesture recognition and practical,patient-centered care.展开更多
Objective To observe the influence of different acupoint combinations on immediate effect of surface electromyography of patients with cervical spondylosis, and to explore the interactions and laws among different acu...Objective To observe the influence of different acupoint combinations on immediate effect of surface electromyography of patients with cervical spondylosis, and to explore the interactions and laws among different acupoint combinations. Methods Acupuncture in three kinds of different acupoint combinations was conducted on 90 patients with cervical spondylosis(three groups): group A [distal point selection group: Kūnlún(昆仑 BL 60) and Hòuxī(后溪 SI 3)]; group B [local point selection group: Fēngchí(风池 GB 20) and Tiānzhù(天柱 BL 10)]; group C(distal and local point selection group: BL 60, SI 3, GB 20 and BL 10). Self control before and after treatment was adopted to observe the mean value of surface electromyography(SEMG) amplitude, to measure the mean values of integrated electromyography(IEMG) and electromyography root mean square(RMS), and to calculate the variation rate of electromyography amplitude of trapezius on the affected side of patients before and after acupuncture. The differences of influences of different acupoint combinations on immediate effect of surface electromyography were compared intra-group, and the differences among the three groups after acupuncture were also compared. Results According to the intragroup comparison before and after acupuncture, the differences of mean value of electromyography amplitude, variation rate of electromyography amplitude, IEMG and RMS were both statistically significant(all P〈0.05). According to the inter-group comparison after acupuncture, the mean value of electromyography amplitude, variation rate of electromyography amplitude, IEMG and RMS varied in different degrees, however, the differences were not significant(all P〉0.05); there was no significant difference in the total effective rate among the three groups(P〉0.05). Conclusion Acupuncture treatment in different acupoint combinations can increase IEMG and RMS and reduce mean value of electromyography amplitude and variation rate of electromyography amplitude, enhance cervical vertebral stability and active contractility of muscle fiber, and improve the fatigue resistance of neck flexion; while, the therapeutic effect of acupuncture on cervical spondylosis has nothing to do with the distance or the number of selected acupoint.展开更多
The research purpose was to improve the accuracy in identifying the prosthetic leg locomotion mode.Surface electromyography(sEMG)combined with high-order zero-crossing was used to identify the prosthetic leg locomotio...The research purpose was to improve the accuracy in identifying the prosthetic leg locomotion mode.Surface electromyography(sEMG)combined with high-order zero-crossing was used to identify the prosthetic leg locomotion modes.sEMG signals recorded from residual thigh muscles were chosen as inputs to pattern classifier for locomotion-mode identification.High-order zero-crossing were computed as the sEMG features regarding locomotion modes.Relevance vector machine(RVM)classifier was investigated.Bat algorithm(BA)was used to compute the RVM classifier kernel function parameters.The classification performance of the particle swarm optimization-relevance vector machine(PSO-RVM)and RVM classifiers was compared.The BA-RVM produced lower classification error in sEMG pattern recognition for the transtibial amputees over a variety of locomotion modes:upslope,downgrade,level-ground walking and stair ascent/descent.展开更多
To explore the mechanisms underlying exercise-induced local muscle fatigue in patients with idiopathic Parkinson's disease (PD),we used surface electromyography to record myoelectric signals from the tibialis anter...To explore the mechanisms underlying exercise-induced local muscle fatigue in patients with idiopathic Parkinson's disease (PD),we used surface electromyography to record myoelectric signals from the tibialis anterior muscle during isometric contraction-induced fatigue until exhaustion.The results revealed no significant differences between patients with idiopathic PD and healthy controls in maximum voluntary contraction of the tibialis anterior muscle.The basic characteristics of surface electromyography were also similar between the two groups.The duration of isometric contraction at 50% maximum voluntary contraction was shortened in PD patients.In addition,PD patients exhibited a stronger increase in mean square amplitude,but a weaker decrease in median frequency and mean power frequency compared with healthy controls during isometric contraction.The skeletal muscles of PD patients revealed specificity of surface electromyography findings,indicating increased fatigability compared with healthy controls.展开更多
BACKGROUND Dystonic gait(DG) is one of clinical symptoms associated with functional dystonia in the functional movement disorders(FMDs). Dystonia is often initiated or worsened by voluntary action and associated with ...BACKGROUND Dystonic gait(DG) is one of clinical symptoms associated with functional dystonia in the functional movement disorders(FMDs). Dystonia is often initiated or worsened by voluntary action and associated with overflow muscle activation. There is no report for DG in FMDs caused by an abnormal pattern in the ankle muscle recruitment strategy during gait.CASE SUMMARY A 52-year-old male patient presented with persistent limping gait. When we requested him to do dorsiflexion and plantar flexion of his ankle in the standing and seating positions, we didn’t see any abnormality. However, we could see the DG during the gait. There were no evidences of common peroneal neuropathy and L5 radiculopathy in the electrodiagnostic study. Magnetic resonance imaging of the lumbar spine, lower leg, and brain had no definite finding. No specific finding was seen in the neurologic examination. For further evaluation, a wireless surface electromyography(EMG) was performed. During the gait, EMG amplitude of left medial and lateral gastrocnemius(GCM) muscles was larger than right medial and lateral GCM muscles. When we analyzed EMG signals for each muscle, there were EMG bursts of double-contraction in the left medial and lateral GCM muscles, while EMG analysis of right medial and lateral GCM muscles noted regular bursts of single contraction. We could find a cause of DG in FMDs.CONCLUSION We report an importance of a wireless surface EMG, in which other examination didn’t reveal the cause of DG in FMDs.展开更多
The loss of speech function due to conditions such as laryngectomy and vocal cord paralysis significantly impacts the quality of life for patients.Achieving effective communication for these patients is a goal pursued...The loss of speech function due to conditions such as laryngectomy and vocal cord paralysis significantly impacts the quality of life for patients.Achieving effective communication for these patients is a goal pursued by researchers.This study primarily explores a method for reconstructing Mandarin speech based on voice-related neck and facial surface electromyography(sEMG).Neck and facial sEMG signals and speech waveform were synchronously collected during normal speech production.A speech reconstruction model for Mandarin speech,based on multi-scale feature extraction from EMG and a generative adversarial network(GAN),was developed.Both subjective and objective evaluations were conducted to assess the speech reconstruction performance of the model.The evaluation results indicate that the model effectively reconstructs speech from neck and facial sEMG signals.The reconstructed speech closely matches the original in terms of spectrogram and fundamental frequency,with mel-cepstrum distortion of 8.45 dB,log F0 RMSE of 0.40,F0 correlation coefficient of 0.71 and F0 voiced/unvoiced estimation accuracy of 0.80.The character error rate of the reconstructed speech is 0.32,while the tone error rate is 0.26.The subjective listening test results show that the naturalness of the reconstructed speech is acceptable,with a mean opinion score greater than 3.This study demonstrates the potential of deep learning techniques in effectively reconstructing Mandarin speech from sEMG.展开更多
Deciphering hand motion intention from surface electromyography(sEMG)encounters challenges posed by the requisites of multiple degrees of freedom(DOFs)and adaptability.Unlike discrete action classification grounded in...Deciphering hand motion intention from surface electromyography(sEMG)encounters challenges posed by the requisites of multiple degrees of freedom(DOFs)and adaptability.Unlike discrete action classification grounded in pattern recognition,the pursuit of continuous kinematics estimation is appreciated for its inherent naturalness and intuitiveness.However,prevailing estimation techniques contend with accuracy limitations and substantial computational demands.Kalman estimation technology,celebrated for its ease of implementation and real-time adaptability,finds extensive application across diverse domains.This study introduces a continuous Kalman estimation method,leveraging a system model with sEMG and joint angles as inputs and outputs.Facilitated by model parameter training methods,the approach deduces multiple DOF finger kinematics simultaneously.The method’s efficacy is validated using a publicly accessible database,yielding a correlation coefficient(CC)of 0.73.With over 45,000 windows for training Kalman model parameters,the average computation time remains under 0.01 s.This pilot study amplifies its potential for further exploration and application within the realm of continuous finger motion estimation technology.展开更多
Background It is believed that defects in upper airway neuromuscular control play a role in sleep apnea pathogenesis. Currently, there is no simple and non-invasive method for evaluating neuromuscular activity for the...Background It is believed that defects in upper airway neuromuscular control play a role in sleep apnea pathogenesis. Currently, there is no simple and non-invasive method for evaluating neuromuscular activity for the purpose of screening in patients with obstructive sleep apnea. This study was designed to assess the validity of chin surface electromyography of routine polysomnography in evaluating the neuromuscular activity of obstructive sleep apnea subjects and probe the neuromuscular contribution in the pathogenesis of the condition. Methods The chin surface electromyography of routine polysomnography during normal breathing and obstructive apnea were quantified in 36 male patients with obstructive sleep apnea. The change of chin surface electromyography from normal breathing to obstructive apnea was expressed as the percent compensated electromyography value, where the percent compensated electromyography value = (normal breath surface electromyography - apnea surface electromyography)/normal breath surface electromyography, and the percent compensated electromyography values among subjects were compared. The relationship between sleep apnea related parameters and the percent compensated electromyography value was examined. Results The percent compensated electromyography value of the subjects varied from 1% to 90% and had a significant positive correlation with apnea hypopnea index (R2=0.382, P 〈0.001). Conclusions Recording and analyzing chin surface electromyography by routine polysomnography is a valid way of screening the neuromuscular activity in patients with obstructive sleep apnea. The neuromuscular contribution is different among subjects with obstructive sleep apnea.展开更多
Recent research has demonstrated that surface electromyography(sEMG)signals have non-Gaussianity and non-linearity properties.It is known that more muscle motor units are recruited and firing rates(FRs)increase as exe...Recent research has demonstrated that surface electromyography(sEMG)signals have non-Gaussianity and non-linearity properties.It is known that more muscle motor units are recruited and firing rates(FRs)increase as exertion increases.A hy-pothesis was proposed that the Gaussianity test(Sg)and linearity test(St)levels of sEMG signals are associated with the num-ber of active motor units(nMUs)and the FR.The hypothesis has only been preliminarily discussed in experimental studies.We used a simulation sEMG model involving spatial(active MUs)and temporal(three FRs)information to test the hypothesis.Higher-order statistics(HOS)from the bi-frequency domain were used to perform Sg and St.Multivariate covariance analysis and a correlation test were employed to determine the nMUs-Sg relationship and the nMUs-St relationship.Results showed that nMUs,the FR,and the interaction of nMUs and the FR all influenced the Sg and St values.The nMUs negatively correlated to both the Sg and St values.That is,at the three FRs,sEMG signals tended to a more Gaussian and linear distribution as exertion and nMUs increased.The study limited experiment factors to the sEMG non-Gaussianity and non-linearity levels.The study quantitatively described nMUs and the FR of muscle that are not directly available from experiments.Our finding has guiding significance for muscle capability assessment and prosthetic control.展开更多
Purpose–Two-handed automobile steering at low vehicle speeds may lead to reduced steering ability at large steering wheel angles and shoulder injury at high steering wheel rates(SWRs).As afirst step toward solving the...Purpose–Two-handed automobile steering at low vehicle speeds may lead to reduced steering ability at large steering wheel angles and shoulder injury at high steering wheel rates(SWRs).As afirst step toward solving these problems,this study aims,firstly,to design a surface electromyography(sEMG)controlled steering assistance interface that enables hands-free steering wheel rotation and,secondly,to validate the effect of this rotation on path-following accuracy.Design/methodology/approach–A total of 24 drivers used biceps brachii sEMG signals to control the steering assistance interface at a maximized SWR in three driving simulator scenarios:U-turn,908 turn and 458 turn.For comparison,the scenarios were repeated with a slower SWR and a game steering wheel in place of the steering assistance interface.The path-following accuracy of the steering assistance interface would be validated if it was at least comparable to that of the game steering wheel.Findings–Overall,the steering assistance interface with a maximized SWR was comparable to a game steering wheel.For the U-turn,908 turn and 458 turn,the sEMG-based human–machine interface(HMI)had median lateral errors of 0.55,0.3 and 0.2 m,respectively,whereas the game steering wheel,respectively,had median lateral errors of 0.7,0.4 and 0.3 m.The higher accuracy of the sEMG-based HMI was statistically significant in the case of the U-turn.Originality/value–Although production automobiles do not use sEMG-based HMIs,and few studies have proposed sEMG controlled steering,the results of the current study warrant further development of a sEMG-based HMI for an actual automobile.展开更多
Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these...Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.展开更多
BACKGROUND Myofascial pain syndrome(MPS)is a common musculoskeletal disease associated with myofascial trigger point(MTrP).Muscle injury is one of the common causes of MPS.Currently,there is no effective treatment for...BACKGROUND Myofascial pain syndrome(MPS)is a common musculoskeletal disease associated with myofascial trigger point(MTrP).Muscle injury is one of the common causes of MPS.Currently,there is no effective treatment for MPS.CASE SUMMARY A 24-year-old female with chronic lower back MPS secondary to quadratus lumborum(QL)injury underwent comprehensive evaluation using validated scales:Pain severity(visual analog scale,McGill Pain Questionnaire),functional disability(Oswestry Disability Index,Roland Morris Disability Questionnaire),and quality of life[short form 36(SF-36)].Objective assessments included sEMG of bilateral QL muscles,Myoton mechanical property analysis,and magnetic resonance imaging volumetric measurements.The patient received four ultrasoundguided platelet-rich plasma(PRP)injections at 4-week intervals,with follow-up evaluations conducted at 1,3,and 6 months post-treatment.CONCLUSION Ultrasound-guided PRP injections alleviated pain,restored function,and improved quality of life in post-traumatic MPS.sEMG demonstrated neuromuscular symmetry restoration in MTrP-affected muscles,supporting the therapeutic potential of PRP.展开更多
In the face of the large number of people with motor function disabilities,rehabilitation robots have attracted more and more attention.In order to promote the active participation of the user's motion intention i...In the face of the large number of people with motor function disabilities,rehabilitation robots have attracted more and more attention.In order to promote the active participation of the user's motion intention in the assisted rehabilitation process of the robots,it is crucial to establish the human motion prediction model.In this paper,a hybrid prediction model built on long short-term memory(LSTM)neural network using surface electromyography(sEMG)is applied to predict the elbow motion of the users in advance.This model includes two sub-models:a back-propagation neural network and an LSTM network.The former extracts a preliminary prediction of the elbow motion,and the latter corrects this prediction to increase accuracy.The proposed model takes time series data as input,which includes the sEMG signals measured by electrodes and the continuous angles from inertial measurement units.The offline and online tests were carried out to verify the established hybrid model.Finally,average root mean square errors of 3.52°and 4.18°were reached respectively for offline and online tests,and the correlation coefficients for both were above 0.98.展开更多
The changes in the evolvement patterns of surface electromyography(EMG)signals during both static and dynamic fatiguing contractions are studied.The main finding is that the EMG signal tends to be more and more regu...The changes in the evolvement patterns of surface electromyography(EMG)signals during both static and dynamic fatiguing contractions are studied.The main finding is that the EMG signal tends to be more and more regular as muscle fatigues.An increase in the summation of all the regular evolvement patterns denoted by Dreg reflects such a tendency.Compared with traditional measurements,Dreg shows less variability among subjects when characterizing a fatigue process.In addition,the calculation of Dreg in the time domain is free from the restrictions disturbing those of spectral parameters.The detection of an increase in the EMG regularity not only proposes a new and easy way to inspect changes in EMG during the fatigue process,but also provides strong supports to estimate muscle fatigue by means of nonlinear analysis methods such as entropy and complexity measures.The detection method of signal regularity can also be applied to other physiological signals.展开更多
Hemiparesis is one of the most common consequences of stroke. Advanced rehabilitation techniques are essential for restoring motor function in hemiplegic patients. Functional electrical stimulation applied to the affe...Hemiparesis is one of the most common consequences of stroke. Advanced rehabilitation techniques are essential for restoring motor function in hemiplegic patients. Functional electrical stimulation applied to the affected limb based on myoelectric signal from the unaffected limb is a promising therapy for hemiplegia. In this study, we developed a prototype system for evaluating this novel functional electrical stimulation-control strategy. Based on surface electromyography and a vector machine model, a self-administered, muki-movement, force-modulation functional electrical stimulation-prototype system for hemiplegia was implemented. This paper discusses the hardware design, the algorithm of the system, and key points of the self-oscillation-prone system. The experimental results demonstrate the feasibility of the prototype system for further clinical trials, which is being conducted to evaluate the efficacy of the proposed rehabilitation technique.展开更多
Objective:To observe the clinical effect of combined acupuncture and kinesiotherapy on upper cross syndrome(UCS) by a parallel randomized clinical trial.Methods:A total of 45 patients with UCS were recruited from the ...Objective:To observe the clinical effect of combined acupuncture and kinesiotherapy on upper cross syndrome(UCS) by a parallel randomized clinical trial.Methods:A total of 45 patients with UCS were recruited from the outpatients of AcupunctureMoxibustion,Tuina and Rehabilitation Department of the First Affiliated Hospital of Hunan University of Chinese Medicine,the students of Hunan University of Chinese Medicine and the patients from the nearby communities in accordance with the inclusion criteria.Using the random number table method,they were divided into a combined treatment group(acupuncture plus kinesiotherapy,23 cases) and a simple kinesiotherapy group(22 patients).Treatment for 4 weeks was one course,and two consecutive courses were required.The visual analog scale(VAS) score,the score of the assessment scale for cervical spondylosis,the value of surface electromyography(root mean square,RMS),and the cervical curvature value were used in the evaluation.The allocation scheme was concealed from the outcome assessors.Results:The data from 23 cases of the combined treatment group and 22 cases of the simple kinesiotherapy group were analyzed.Before treatment,the differences were not statistically significant in the general conditions,VAS score,assessment score of cervical spondylosis,cervical curvature value,and RMS in UCS patients between the two groups(all P> 0.05).After treatment,the VAS score was reduced compared with that before treatment in both groups(all P <0.05).In two courses of treatment,the VAS score decreased as compared with that in one course of treatment in both groups(both P <0.05),and the VAS score in the combined treatment group decreased more obviously after each course of treatment(both P <0.05).The RMS decreased compared with that before treatment in each group(both P <0.05),and the decrease in the combined treatment group was more obvious(P <0.05).After treatment of each course,the assessment score was all increased as compared with that before treatment in two groups(all P <0.05).In two courses of treatment,the assessment score was increased as compared with that in one course of treatment in both groups(both P <0.05),and the score in the combined treatment group was increased more obviously in the two courses of treatment(P <0.05).Regarding either the intra-group comparison or the inter-group comparison before and after treatment,the differences were not statistically significant(all P> 0.05),suggesting no obvious improvement of cervical curvature in the two courses of treatment in patients with UCS.However,cervical curvature tended to improve in the combined treatment group.The total effective rate was significantly different between the two groups(P <0.05),indicating that the total effective rate in the combined treatment group was better than that in the simple kinesiotherapy group.No any adverse reactions occurred.Conclusion:Combined treatment with acupuncture,kinesiotherapy,and kinesiotherapy alleviated pain,relieved the symptoms and physical signs,and improved the daily movement of the patients.However,the combined treatment of acupuncture and kinesiotherapy had a much better effect on UCS.展开更多
BACKGROUND Paraspinal muscle strength and fatigue are considered important in low back pain(LBP)prevention and rehabilitation.High reliability of paraspinal strength and electromyographic(EMG)-fatigue parameters has n...BACKGROUND Paraspinal muscle strength and fatigue are considered important in low back pain(LBP)prevention and rehabilitation.High reliability of paraspinal strength and electromyographic(EMG)-fatigue parameters has not been universally reported.Moreover,the discriminative validity of these parameters requires further exploration,under the threat of potentially poor reliability of the methods examined.AIM To investigate the reliability and discriminative validity of paraspinal strength and EMG-related fatigue in subjects with recurrent LBP and healthy participants.METHODS Test-retest measurements were performed in 26 healthy and 66 LBP volunteers,for reliability.Paraspinal isometric maximal and mean strength were determined with a maximum voluntary isometric contraction(MVIC)protocol,performed in a custom-made device.For the fatigue test,participants performed a 60% MIVC level continuous isometric contraction of the paraspinals,in conjunction with EMG analysis from 4 muscle sites of the lumbar spine.Initial median frequency(IMF),the median frequency slope(MFslope),as well as the root mean square(RMS)slope EMG parameters were used as fatigue measures.Data were analysed with repeated measures ANOVA for test-retest differences.For reliability,the intraclass correlation coefficient(ICC3,1),standard error of the measurement(SEM)and the smallest detectable difference(SDD)were reported.Group-related differences for fatigue measures were analysed with a Multivariate Analysis of Covariance,with age,weight and strength as covariates.RESULTS Isometric strength presented statistically significant between-day differences(P<0.01),however these did not exceed 10%(healthy:7.2%/LBP-patients:9.7%)and ICC reliability values were excellent,yet test-retest error was increased for the patient group(healthy:ICC3,1:0.92-0.96,SEM:5.72-5.94 Hz,SDD:18.51%-18.57%/LBP-patients:ICC3,1:0.91-0.96,SEM:6.49-6.96,SDD:30.75%-31.61%).For the frequency data,IMF reliability was excellent(healthy:ICC3,1:0.91-0.94,SEM:3.45-7.27 Hz,SDD:9.56%-20.14%/patients:ICC3,1:0.90-0.94,SEM:6.41-7.59 Hz,SDD:17.75%-21.02%)and of MF raw and normalised slopes was good(healthy:ICC3,1:0.78-0.82,SEM:4.93-6.02 Hz,SDD:13.66-16.67%/LBP-patients:ICC3,1:0.83-0.85,SEM:6.75-7.47 Hz,SDD:18.69%-20.69%).However,the reliability for RMS data presented unacceptably high SDD values and were not considered further.For discriminative validity,less MVIC and less steep MFslopes were registered for the patient group(P<0.01).CONCLUSION Reliability and discriminative ability of paraspinal strength and EMG-related frequency parameters were demonstrated in healthy participants and patients with LBP.展开更多
Surface Electromyography(sEMG)plays a key role in many applications such as control of Human-Machine Interfaces(HMI)and neuromusculoskeletal modeling.It has strongly nonlinear relations to joint kinematics and reflect...Surface Electromyography(sEMG)plays a key role in many applications such as control of Human-Machine Interfaces(HMI)and neuromusculoskeletal modeling.It has strongly nonlinear relations to joint kinematics and reflects the subjects’intention in moving their limbs.Such relations have been traditionally examined by either integrated biomechanics and multi-body dynamics or gesture-based classification approaches.However,these methods have drawbacks that limit their usability.Different from them,joint kinematics can be continuously reconstructed from sEMG via estimation approaches,for instance,the Artificial Neural Networks(ANNs).The Comparison of different ANNs used in different studies is difficult,and in many cases,impossible.The current study focuses on fairly evaluating four types of ANN over the same dataset and conditions in proportional and simultaneous estimation of 15 hand joint angles from 10 sEMG signals.The presented ANNs are Feedforward,Cascade-Forward,Radial Basis Function(RBFNN),and Generalized Regression(GRNN).Each ANN is applied to its special parametric study.All the methods efficiently solved the regression problem of the complex multi-input multi-output bio-system.The RBFNN has the best performance over the others with a 79.80%mean correlation coefficient over all joints,and its accuracy reaches as high as 92.67%in some joints.Interestingly,the highest accuracy over individual joints is 93.46%,which is achieved via the GRNN.The good accuracy suggests that the proposed approaches can be used as alternatives to the previously adopted ones and can be employed effectively to synchronously control multi-degrees of freedom HMI and for general multi-joint kinematics estimation purposes.展开更多
A surface electromyography(sEMG)signal acquisition circuit based on high-order filtering is designed.We use a two-stage adjustable amplifier and a high-order Sallen-Key bandpass filter to solve the problems of non-adj...A surface electromyography(sEMG)signal acquisition circuit based on high-order filtering is designed.We use a two-stage adjustable amplifier and a high-order Sallen-Key bandpass filter to solve the problems of non-adjustable amplification gain and low filtering order in traditional acquisition circuits.The experimental results show that the designed sEMG signal acquisition device can eliminate power frequency interference effectively,the stopband drop of the filtering part reaches approximately-100 dB/dec,which can effectively extract useful signals between 20-500 Hz,and the amplification gain reaches 60 dB.展开更多
基金supported by the National Natural Science Foundation of China(72061006)the research on the auxiliary diagnosis system of chronic injury of levator scapulae based on the concept of digital twin(Contract No:Qian Kehe Support[2023]General 117)Research on indoor intelligent assisted walking robot for the rehabilitation of walking ability of the elderly(Contract No:Qian kehe Support[2023]General 124).
文摘Stroke survivors often face significant challenges when performing daily self-care activities due to upper limb motor impairments.Traditional surface electromyography(sEMG)analysis typically focuses on isolated hand postures,overlooking the complexity of object-interactive behaviors that are crucial for promoting patient independence.This study introduces a novel framework that combines high-density sEMG(HD-sEMG)signals with an improved Whale Optimization Algorithm(IWOA)-optimized Long Short-Term Memory(LSTM)network to address this limitation.The key contributions of this work include:(1)the creation of a specialized HD-sEMG dataset that captures nine continuous self-care behaviors,along with time and posture markers,to better reflect real-world patient interactions;(2)the development of a multi-channel feature fusion module based on Pascal’s theorem,which enables efficient signal segmentation and spatial–temporal feature extraction;and(3)the enhancement of the IWOA algorithm,which integrates optimal point set initialization,a diversity-driven pooling mechanism,and cosine-based differential evolution to optimize LSTM hyperparameters,thereby improving convergence and global search capabilities.Experimental results demonstrate superior performance,achieving 99.58%accuracy in self-care behavior recognition and 86.19%accuracy for 17 continuous gestures on the Ninapro db2 benchmark.The framework operates with low latency,meeting the real-time requirements for assistive devices.By enabling precise,context-aware recognition of daily activities,this work advances personalized rehabilitation technologies,empowering stroke patients to regain autonomy in self-care tasks.The proposed methodology offers a robust,scalable solution for clinical applications,bridging the gap between laboratory-based gesture recognition and practical,patient-centered care.
基金Supported by “The 12th five-year plan” programmed project of educational science in Hubei Province:2014B095
文摘Objective To observe the influence of different acupoint combinations on immediate effect of surface electromyography of patients with cervical spondylosis, and to explore the interactions and laws among different acupoint combinations. Methods Acupuncture in three kinds of different acupoint combinations was conducted on 90 patients with cervical spondylosis(three groups): group A [distal point selection group: Kūnlún(昆仑 BL 60) and Hòuxī(后溪 SI 3)]; group B [local point selection group: Fēngchí(风池 GB 20) and Tiānzhù(天柱 BL 10)]; group C(distal and local point selection group: BL 60, SI 3, GB 20 and BL 10). Self control before and after treatment was adopted to observe the mean value of surface electromyography(SEMG) amplitude, to measure the mean values of integrated electromyography(IEMG) and electromyography root mean square(RMS), and to calculate the variation rate of electromyography amplitude of trapezius on the affected side of patients before and after acupuncture. The differences of influences of different acupoint combinations on immediate effect of surface electromyography were compared intra-group, and the differences among the three groups after acupuncture were also compared. Results According to the intragroup comparison before and after acupuncture, the differences of mean value of electromyography amplitude, variation rate of electromyography amplitude, IEMG and RMS were both statistically significant(all P〈0.05). According to the inter-group comparison after acupuncture, the mean value of electromyography amplitude, variation rate of electromyography amplitude, IEMG and RMS varied in different degrees, however, the differences were not significant(all P〉0.05); there was no significant difference in the total effective rate among the three groups(P〉0.05). Conclusion Acupuncture treatment in different acupoint combinations can increase IEMG and RMS and reduce mean value of electromyography amplitude and variation rate of electromyography amplitude, enhance cervical vertebral stability and active contractility of muscle fiber, and improve the fatigue resistance of neck flexion; while, the therapeutic effect of acupuncture on cervical spondylosis has nothing to do with the distance or the number of selected acupoint.
基金the Center Plain Science and Technology Innovation Talents(No.194200510016)the Science and Technology Innovation Team Project of Henan Province University(No.19IRTSTHN013)the Key Scien-tific Research Support Project for Institutions of Higher Learning in Henan Province(No.18A413014)。
文摘The research purpose was to improve the accuracy in identifying the prosthetic leg locomotion mode.Surface electromyography(sEMG)combined with high-order zero-crossing was used to identify the prosthetic leg locomotion modes.sEMG signals recorded from residual thigh muscles were chosen as inputs to pattern classifier for locomotion-mode identification.High-order zero-crossing were computed as the sEMG features regarding locomotion modes.Relevance vector machine(RVM)classifier was investigated.Bat algorithm(BA)was used to compute the RVM classifier kernel function parameters.The classification performance of the particle swarm optimization-relevance vector machine(PSO-RVM)and RVM classifiers was compared.The BA-RVM produced lower classification error in sEMG pattern recognition for the transtibial amputees over a variety of locomotion modes:upslope,downgrade,level-ground walking and stair ascent/descent.
文摘To explore the mechanisms underlying exercise-induced local muscle fatigue in patients with idiopathic Parkinson's disease (PD),we used surface electromyography to record myoelectric signals from the tibialis anterior muscle during isometric contraction-induced fatigue until exhaustion.The results revealed no significant differences between patients with idiopathic PD and healthy controls in maximum voluntary contraction of the tibialis anterior muscle.The basic characteristics of surface electromyography were also similar between the two groups.The duration of isometric contraction at 50% maximum voluntary contraction was shortened in PD patients.In addition,PD patients exhibited a stronger increase in mean square amplitude,but a weaker decrease in median frequency and mean power frequency compared with healthy controls during isometric contraction.The skeletal muscles of PD patients revealed specificity of surface electromyography findings,indicating increased fatigability compared with healthy controls.
文摘BACKGROUND Dystonic gait(DG) is one of clinical symptoms associated with functional dystonia in the functional movement disorders(FMDs). Dystonia is often initiated or worsened by voluntary action and associated with overflow muscle activation. There is no report for DG in FMDs caused by an abnormal pattern in the ankle muscle recruitment strategy during gait.CASE SUMMARY A 52-year-old male patient presented with persistent limping gait. When we requested him to do dorsiflexion and plantar flexion of his ankle in the standing and seating positions, we didn’t see any abnormality. However, we could see the DG during the gait. There were no evidences of common peroneal neuropathy and L5 radiculopathy in the electrodiagnostic study. Magnetic resonance imaging of the lumbar spine, lower leg, and brain had no definite finding. No specific finding was seen in the neurologic examination. For further evaluation, a wireless surface electromyography(EMG) was performed. During the gait, EMG amplitude of left medial and lateral gastrocnemius(GCM) muscles was larger than right medial and lateral GCM muscles. When we analyzed EMG signals for each muscle, there were EMG bursts of double-contraction in the left medial and lateral GCM muscles, while EMG analysis of right medial and lateral GCM muscles noted regular bursts of single contraction. We could find a cause of DG in FMDs.CONCLUSION We report an importance of a wireless surface EMG, in which other examination didn’t reveal the cause of DG in FMDs.
基金supported by the National Natural Science Foundation of China,China(Grant 12372299 and Grant 32071315)partly supported by JST CREST,Japan(Grant JPMJCR19A3).
文摘The loss of speech function due to conditions such as laryngectomy and vocal cord paralysis significantly impacts the quality of life for patients.Achieving effective communication for these patients is a goal pursued by researchers.This study primarily explores a method for reconstructing Mandarin speech based on voice-related neck and facial surface electromyography(sEMG).Neck and facial sEMG signals and speech waveform were synchronously collected during normal speech production.A speech reconstruction model for Mandarin speech,based on multi-scale feature extraction from EMG and a generative adversarial network(GAN),was developed.Both subjective and objective evaluations were conducted to assess the speech reconstruction performance of the model.The evaluation results indicate that the model effectively reconstructs speech from neck and facial sEMG signals.The reconstructed speech closely matches the original in terms of spectrogram and fundamental frequency,with mel-cepstrum distortion of 8.45 dB,log F0 RMSE of 0.40,F0 correlation coefficient of 0.71 and F0 voiced/unvoiced estimation accuracy of 0.80.The character error rate of the reconstructed speech is 0.32,while the tone error rate is 0.26.The subjective listening test results show that the naturalness of the reconstructed speech is acceptable,with a mean opinion score greater than 3.This study demonstrates the potential of deep learning techniques in effectively reconstructing Mandarin speech from sEMG.
基金supported in part by the National Key R&D Program of China(#2020YFC2007900)the National Natural Science Foundation of China(#82161160341,#62271477,and #61901464)+2 种基金the Science and Technology Program of Guangdong Province(#2022A0505090007)“The Belt and Road”Innovative Talent Exchange program for foreign experts(DL2022024002L)Jinan 5150 Program for Talents Introduction.
文摘Deciphering hand motion intention from surface electromyography(sEMG)encounters challenges posed by the requisites of multiple degrees of freedom(DOFs)and adaptability.Unlike discrete action classification grounded in pattern recognition,the pursuit of continuous kinematics estimation is appreciated for its inherent naturalness and intuitiveness.However,prevailing estimation techniques contend with accuracy limitations and substantial computational demands.Kalman estimation technology,celebrated for its ease of implementation and real-time adaptability,finds extensive application across diverse domains.This study introduces a continuous Kalman estimation method,leveraging a system model with sEMG and joint angles as inputs and outputs.Facilitated by model parameter training methods,the approach deduces multiple DOF finger kinematics simultaneously.The method’s efficacy is validated using a publicly accessible database,yielding a correlation coefficient(CC)of 0.73.With over 45,000 windows for training Kalman model parameters,the average computation time remains under 0.01 s.This pilot study amplifies its potential for further exploration and application within the realm of continuous finger motion estimation technology.
基金This work was supported by grants from the National Natural Science Foundation of China (No. 30672304, 30730100).
文摘Background It is believed that defects in upper airway neuromuscular control play a role in sleep apnea pathogenesis. Currently, there is no simple and non-invasive method for evaluating neuromuscular activity for the purpose of screening in patients with obstructive sleep apnea. This study was designed to assess the validity of chin surface electromyography of routine polysomnography in evaluating the neuromuscular activity of obstructive sleep apnea subjects and probe the neuromuscular contribution in the pathogenesis of the condition. Methods The chin surface electromyography of routine polysomnography during normal breathing and obstructive apnea were quantified in 36 male patients with obstructive sleep apnea. The change of chin surface electromyography from normal breathing to obstructive apnea was expressed as the percent compensated electromyography value, where the percent compensated electromyography value = (normal breath surface electromyography - apnea surface electromyography)/normal breath surface electromyography, and the percent compensated electromyography values among subjects were compared. The relationship between sleep apnea related parameters and the percent compensated electromyography value was examined. Results The percent compensated electromyography value of the subjects varied from 1% to 90% and had a significant positive correlation with apnea hypopnea index (R2=0.382, P 〈0.001). Conclusions Recording and analyzing chin surface electromyography by routine polysomnography is a valid way of screening the neuromuscular activity in patients with obstructive sleep apnea. The neuromuscular contribution is different among subjects with obstructive sleep apnea.
基金supported by the National High Technology Research and Development Program of China and the National Basic Research Program of China (Grant No. 2011CB7000)
文摘Recent research has demonstrated that surface electromyography(sEMG)signals have non-Gaussianity and non-linearity properties.It is known that more muscle motor units are recruited and firing rates(FRs)increase as exertion increases.A hy-pothesis was proposed that the Gaussianity test(Sg)and linearity test(St)levels of sEMG signals are associated with the num-ber of active motor units(nMUs)and the FR.The hypothesis has only been preliminarily discussed in experimental studies.We used a simulation sEMG model involving spatial(active MUs)and temporal(three FRs)information to test the hypothesis.Higher-order statistics(HOS)from the bi-frequency domain were used to perform Sg and St.Multivariate covariance analysis and a correlation test were employed to determine the nMUs-Sg relationship and the nMUs-St relationship.Results showed that nMUs,the FR,and the interaction of nMUs and the FR all influenced the Sg and St values.The nMUs negatively correlated to both the Sg and St values.That is,at the three FRs,sEMG signals tended to a more Gaussian and linear distribution as exertion and nMUs increased.The study limited experiment factors to the sEMG non-Gaussianity and non-linearity levels.The study quantitatively described nMUs and the FR of muscle that are not directly available from experiments.Our finding has guiding significance for muscle capability assessment and prosthetic control.
文摘Purpose–Two-handed automobile steering at low vehicle speeds may lead to reduced steering ability at large steering wheel angles and shoulder injury at high steering wheel rates(SWRs).As afirst step toward solving these problems,this study aims,firstly,to design a surface electromyography(sEMG)controlled steering assistance interface that enables hands-free steering wheel rotation and,secondly,to validate the effect of this rotation on path-following accuracy.Design/methodology/approach–A total of 24 drivers used biceps brachii sEMG signals to control the steering assistance interface at a maximized SWR in three driving simulator scenarios:U-turn,908 turn and 458 turn.For comparison,the scenarios were repeated with a slower SWR and a game steering wheel in place of the steering assistance interface.The path-following accuracy of the steering assistance interface would be validated if it was at least comparable to that of the game steering wheel.Findings–Overall,the steering assistance interface with a maximized SWR was comparable to a game steering wheel.For the U-turn,908 turn and 458 turn,the sEMG-based human–machine interface(HMI)had median lateral errors of 0.55,0.3 and 0.2 m,respectively,whereas the game steering wheel,respectively,had median lateral errors of 0.7,0.4 and 0.3 m.The higher accuracy of the sEMG-based HMI was statistically significant in the case of the U-turn.Originality/value–Although production automobiles do not use sEMG-based HMIs,and few studies have proposed sEMG controlled steering,the results of the current study warrant further development of a sEMG-based HMI for an actual automobile.
基金supported by the Fundamental Research Funds for Central Public Welfare Research Institute,No.2020CZ-5(to WS and GS)the National Natural Science Foundation of China,No.31970970(to JSR)Fundamental Research Funds for the Central Universities,No.YWF-23-YG-QB-010(to JSR)。
文摘Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.
文摘BACKGROUND Myofascial pain syndrome(MPS)is a common musculoskeletal disease associated with myofascial trigger point(MTrP).Muscle injury is one of the common causes of MPS.Currently,there is no effective treatment for MPS.CASE SUMMARY A 24-year-old female with chronic lower back MPS secondary to quadratus lumborum(QL)injury underwent comprehensive evaluation using validated scales:Pain severity(visual analog scale,McGill Pain Questionnaire),functional disability(Oswestry Disability Index,Roland Morris Disability Questionnaire),and quality of life[short form 36(SF-36)].Objective assessments included sEMG of bilateral QL muscles,Myoton mechanical property analysis,and magnetic resonance imaging volumetric measurements.The patient received four ultrasoundguided platelet-rich plasma(PRP)injections at 4-week intervals,with follow-up evaluations conducted at 1,3,and 6 months post-treatment.CONCLUSION Ultrasound-guided PRP injections alleviated pain,restored function,and improved quality of life in post-traumatic MPS.sEMG demonstrated neuromuscular symmetry restoration in MTrP-affected muscles,supporting the therapeutic potential of PRP.
基金the National Key Research and Development Program of China(No.2020YFC2007500)the Science and Technology Commission of Shanghai Municipality(No.20DZ2220400)。
文摘In the face of the large number of people with motor function disabilities,rehabilitation robots have attracted more and more attention.In order to promote the active participation of the user's motion intention in the assisted rehabilitation process of the robots,it is crucial to establish the human motion prediction model.In this paper,a hybrid prediction model built on long short-term memory(LSTM)neural network using surface electromyography(sEMG)is applied to predict the elbow motion of the users in advance.This model includes two sub-models:a back-propagation neural network and an LSTM network.The former extracts a preliminary prediction of the elbow motion,and the latter corrects this prediction to increase accuracy.The proposed model takes time series data as input,which includes the sEMG signals measured by electrodes and the continuous angles from inertial measurement units.The offline and online tests were carried out to verify the established hybrid model.Finally,average root mean square errors of 3.52°and 4.18°were reached respectively for offline and online tests,and the correlation coefficients for both were above 0.98.
基金The National Basic Research Program of China(973Program)(No.2005CB724303)the Natural Science Foundation of Shanghai(No.09ZR1409600)the Shanghai Leading Academic Discipline Project(No.B412)
文摘The changes in the evolvement patterns of surface electromyography(EMG)signals during both static and dynamic fatiguing contractions are studied.The main finding is that the EMG signal tends to be more and more regular as muscle fatigues.An increase in the summation of all the regular evolvement patterns denoted by Dreg reflects such a tendency.Compared with traditional measurements,Dreg shows less variability among subjects when characterizing a fatigue process.In addition,the calculation of Dreg in the time domain is free from the restrictions disturbing those of spectral parameters.The detection of an increase in the EMG regularity not only proposes a new and easy way to inspect changes in EMG during the fatigue process,but also provides strong supports to estimate muscle fatigue by means of nonlinear analysis methods such as entropy and complexity measures.The detection method of signal regularity can also be applied to other physiological signals.
基金supported by the National Natural Science Foundation of China,No.90307013,90707005a grant from the Science&Technology Pillar Program of Jiangsu Province in China,No.BE2013706
文摘Hemiparesis is one of the most common consequences of stroke. Advanced rehabilitation techniques are essential for restoring motor function in hemiplegic patients. Functional electrical stimulation applied to the affected limb based on myoelectric signal from the unaffected limb is a promising therapy for hemiplegia. In this study, we developed a prototype system for evaluating this novel functional electrical stimulation-control strategy. Based on surface electromyography and a vector machine model, a self-administered, muki-movement, force-modulation functional electrical stimulation-prototype system for hemiplegia was implemented. This paper discusses the hardware design, the algorithm of the system, and key points of the self-oscillation-prone system. The experimental results demonstrate the feasibility of the prototype system for further clinical trials, which is being conducted to evaluate the efficacy of the proposed rehabilitation technique.
基金Supported by Leading Talents Training Program of Hunan Province High-Level Health Talents 225 Project (Hunan Health-20N9-N9S)。
文摘Objective:To observe the clinical effect of combined acupuncture and kinesiotherapy on upper cross syndrome(UCS) by a parallel randomized clinical trial.Methods:A total of 45 patients with UCS were recruited from the outpatients of AcupunctureMoxibustion,Tuina and Rehabilitation Department of the First Affiliated Hospital of Hunan University of Chinese Medicine,the students of Hunan University of Chinese Medicine and the patients from the nearby communities in accordance with the inclusion criteria.Using the random number table method,they were divided into a combined treatment group(acupuncture plus kinesiotherapy,23 cases) and a simple kinesiotherapy group(22 patients).Treatment for 4 weeks was one course,and two consecutive courses were required.The visual analog scale(VAS) score,the score of the assessment scale for cervical spondylosis,the value of surface electromyography(root mean square,RMS),and the cervical curvature value were used in the evaluation.The allocation scheme was concealed from the outcome assessors.Results:The data from 23 cases of the combined treatment group and 22 cases of the simple kinesiotherapy group were analyzed.Before treatment,the differences were not statistically significant in the general conditions,VAS score,assessment score of cervical spondylosis,cervical curvature value,and RMS in UCS patients between the two groups(all P> 0.05).After treatment,the VAS score was reduced compared with that before treatment in both groups(all P <0.05).In two courses of treatment,the VAS score decreased as compared with that in one course of treatment in both groups(both P <0.05),and the VAS score in the combined treatment group decreased more obviously after each course of treatment(both P <0.05).The RMS decreased compared with that before treatment in each group(both P <0.05),and the decrease in the combined treatment group was more obvious(P <0.05).After treatment of each course,the assessment score was all increased as compared with that before treatment in two groups(all P <0.05).In two courses of treatment,the assessment score was increased as compared with that in one course of treatment in both groups(both P <0.05),and the score in the combined treatment group was increased more obviously in the two courses of treatment(P <0.05).Regarding either the intra-group comparison or the inter-group comparison before and after treatment,the differences were not statistically significant(all P> 0.05),suggesting no obvious improvement of cervical curvature in the two courses of treatment in patients with UCS.However,cervical curvature tended to improve in the combined treatment group.The total effective rate was significantly different between the two groups(P <0.05),indicating that the total effective rate in the combined treatment group was better than that in the simple kinesiotherapy group.No any adverse reactions occurred.Conclusion:Combined treatment with acupuncture,kinesiotherapy,and kinesiotherapy alleviated pain,relieved the symptoms and physical signs,and improved the daily movement of the patients.However,the combined treatment of acupuncture and kinesiotherapy had a much better effect on UCS.
基金Supported by Greek State Scholarships Foundation(IKY),Athens,Greece,No.T104830098Hospital Saving Association(HSA),London,United Kingdom,No.99/2.
文摘BACKGROUND Paraspinal muscle strength and fatigue are considered important in low back pain(LBP)prevention and rehabilitation.High reliability of paraspinal strength and electromyographic(EMG)-fatigue parameters has not been universally reported.Moreover,the discriminative validity of these parameters requires further exploration,under the threat of potentially poor reliability of the methods examined.AIM To investigate the reliability and discriminative validity of paraspinal strength and EMG-related fatigue in subjects with recurrent LBP and healthy participants.METHODS Test-retest measurements were performed in 26 healthy and 66 LBP volunteers,for reliability.Paraspinal isometric maximal and mean strength were determined with a maximum voluntary isometric contraction(MVIC)protocol,performed in a custom-made device.For the fatigue test,participants performed a 60% MIVC level continuous isometric contraction of the paraspinals,in conjunction with EMG analysis from 4 muscle sites of the lumbar spine.Initial median frequency(IMF),the median frequency slope(MFslope),as well as the root mean square(RMS)slope EMG parameters were used as fatigue measures.Data were analysed with repeated measures ANOVA for test-retest differences.For reliability,the intraclass correlation coefficient(ICC3,1),standard error of the measurement(SEM)and the smallest detectable difference(SDD)were reported.Group-related differences for fatigue measures were analysed with a Multivariate Analysis of Covariance,with age,weight and strength as covariates.RESULTS Isometric strength presented statistically significant between-day differences(P<0.01),however these did not exceed 10%(healthy:7.2%/LBP-patients:9.7%)and ICC reliability values were excellent,yet test-retest error was increased for the patient group(healthy:ICC3,1:0.92-0.96,SEM:5.72-5.94 Hz,SDD:18.51%-18.57%/LBP-patients:ICC3,1:0.91-0.96,SEM:6.49-6.96,SDD:30.75%-31.61%).For the frequency data,IMF reliability was excellent(healthy:ICC3,1:0.91-0.94,SEM:3.45-7.27 Hz,SDD:9.56%-20.14%/patients:ICC3,1:0.90-0.94,SEM:6.41-7.59 Hz,SDD:17.75%-21.02%)and of MF raw and normalised slopes was good(healthy:ICC3,1:0.78-0.82,SEM:4.93-6.02 Hz,SDD:13.66-16.67%/LBP-patients:ICC3,1:0.83-0.85,SEM:6.75-7.47 Hz,SDD:18.69%-20.69%).However,the reliability for RMS data presented unacceptably high SDD values and were not considered further.For discriminative validity,less MVIC and less steep MFslopes were registered for the patient group(P<0.01).CONCLUSION Reliability and discriminative ability of paraspinal strength and EMG-related frequency parameters were demonstrated in healthy participants and patients with LBP.
基金This work is funded by the Deanship of Research at Jordan University of Science and Technology,Grant number 20180035.
文摘Surface Electromyography(sEMG)plays a key role in many applications such as control of Human-Machine Interfaces(HMI)and neuromusculoskeletal modeling.It has strongly nonlinear relations to joint kinematics and reflects the subjects’intention in moving their limbs.Such relations have been traditionally examined by either integrated biomechanics and multi-body dynamics or gesture-based classification approaches.However,these methods have drawbacks that limit their usability.Different from them,joint kinematics can be continuously reconstructed from sEMG via estimation approaches,for instance,the Artificial Neural Networks(ANNs).The Comparison of different ANNs used in different studies is difficult,and in many cases,impossible.The current study focuses on fairly evaluating four types of ANN over the same dataset and conditions in proportional and simultaneous estimation of 15 hand joint angles from 10 sEMG signals.The presented ANNs are Feedforward,Cascade-Forward,Radial Basis Function(RBFNN),and Generalized Regression(GRNN).Each ANN is applied to its special parametric study.All the methods efficiently solved the regression problem of the complex multi-input multi-output bio-system.The RBFNN has the best performance over the others with a 79.80%mean correlation coefficient over all joints,and its accuracy reaches as high as 92.67%in some joints.Interestingly,the highest accuracy over individual joints is 93.46%,which is achieved via the GRNN.The good accuracy suggests that the proposed approaches can be used as alternatives to the previously adopted ones and can be employed effectively to synchronously control multi-degrees of freedom HMI and for general multi-joint kinematics estimation purposes.
基金Science and Technology Plan Project of Weinan City(No.2020ZDYF-JCYJ-177)Power Supply Technology Innovation Team of Shaanxi Railway Engineering Vocational and Technical College(No.KJTD201901)Graduate Program Funded Project of Shaanxi Railway Engineering Vocational and Technical College Scientific Research Fund(No.KY2018-77)。
文摘A surface electromyography(sEMG)signal acquisition circuit based on high-order filtering is designed.We use a two-stage adjustable amplifier and a high-order Sallen-Key bandpass filter to solve the problems of non-adjustable amplification gain and low filtering order in traditional acquisition circuits.The experimental results show that the designed sEMG signal acquisition device can eliminate power frequency interference effectively,the stopband drop of the filtering part reaches approximately-100 dB/dec,which can effectively extract useful signals between 20-500 Hz,and the amplification gain reaches 60 dB.