BACKGROUND Functional epiphora is a clinical condition which is not due to an anatomic defect.Most studies agree that it involves the action of the orbicularis oculi muscle,particularly its deeper segment(Horner’s mu...BACKGROUND Functional epiphora is a clinical condition which is not due to an anatomic defect.Most studies agree that it involves the action of the orbicularis oculi muscle,particularly its deeper segment(Horner’s muscle),but the exact mechanism is not clear.AIM To evaluate the orbicularis oculi muscle in functional epiphora patients using electromyography(EMG).METHODS A total of 8 Chinese patients(16 eyes)with functional epiphora were enrolled in this study,and ten volunteers(10 eyes)were included as normal controls.Five epiphora patients(five eyes)with facial palsy served as positive controls.Quantitative EMG was performed in the deeper segment of orbicularis oculi muscle.The average duration of each EMG waveform was measured.RESULTS The average duration of EMG waveforms in the normal control group,the functional epiphora group,and the facial palsy group were 6.39±0.73 ms,9.39±1.32 ms and 11.2±1.42 ms,respectively.The duration of EMG waveforms was significantly longer in the functional epiphora group than in the normal control group(P<0.05),and shorter than that in the facial palsy group(P<0.05).CONCLUSION These data indicate the presence of neurogenic orbicularis oculi muscle damage in epiphora patients,which may be the cause of functional epiphora.The etiology of neurogenic damage in the orbicularis oculi muscle requires further investigation.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
Sports compression garments are common-selected sportswear to improve athletic performance and reduce sports injury. Since they consist of elastic textile that exerts compression and pressure onto the muscle,muscle ac...Sports compression garments are common-selected sportswear to improve athletic performance and reduce sports injury. Since they consist of elastic textile that exerts compression and pressure onto the muscle,muscle activation is of interest to sports compression garment manufactures who seek to enhance sports performance through gradient compression garment design.However,there are few scientific investigations to explore this effect of muscle activation to evaluate the performance of sports compression garments during sport activity. In this paper, a systemic experimental protocol was presented to improve the quality of evaluation test under a standardized running test. Then muscle activation with and without wearing sport compression garments to highlight the changes caused by compression garment was investigated. The electromyography( EMG) signal was collected and processed by the proposed method to represent the muscle activation combined with gait analysis of running. As a result,the average muscle activation of gait cycle for the major muscles such as rectus femoris( RF) and gastrocnemius medialis( GM) revealed that they needed to exert more muscle force without wearing garment at certain periods for mid-stand and pre-swing phase within gait cycle. These lower muscle activation levels prolonged activity duration,reduced fatigue,and presented low risk for sport injury.Such an evaluation study therefore would scientifically prove the effect of compression garment and provide information on muscle activation and the ergonomic efficacy of gradient compression garment design.展开更多
BACKGROUND Bruxism is a rhythmic masticatory muscle activity that occurs involuntarily in a non-physiologically functional state.There is a lack of research classifying the functional status of masticatory muscles in ...BACKGROUND Bruxism is a rhythmic masticatory muscle activity that occurs involuntarily in a non-physiologically functional state.There is a lack of research classifying the functional status of masticatory muscles in patients with different mandibular movement types(centric clenching or eccentric grinding)of bruxism.AIM To assess the differences of the masticatory muscle activity in patients with different types of bruxism.METHODS A total of 21 subjects with centric bruxism(CB)and 21 subjects with eccentric bruxism(ECB)were screened from college students according to a questionnaire and their tooth wear features.Sixteen subjects with no bruxism were also recruited.The surface electromyography(EMG)signals of the temporalis anterior(TA)and superficial masseter muscle(MM)were measured in different mandibular positions and during the chewing task.The EMG amplitude and chewing cycle duration parameters were then analyzed.RESULTS The CB group showed fewer muscle maximal motor units,with the MM being more pronounced,a higher proportion of muscle contractions to be recruited for the same load of chewing activity,and a longer chewing cycle.The ECB group showed more TA maximal motor units and higher MM activity on the nonworking side in unilateral chewing.CONCLUSION CB mainly affects the MM,and patients with CB show reduced masticatory muscle contraction efficiency and chewing cycle efficiency.ECB mainly affects the TA,and patients with ECB show enhanced contraction of non-functional lateral muscle bundles.展开更多
This study is to investigate the changes of back muscle electromyography (EMG) in occupational low back pain (LBP) patients pre-and post-rehabilitation.20 occupational LBP patients were asked to perform sepcially desi...This study is to investigate the changes of back muscle electromyography (EMG) in occupational low back pain (LBP) patients pre-and post-rehabilitation.20 occupational LBP patients were asked to perform sepcially designed symmetrical and asymmetrical actions,which include"carrying"weights up and down with a 45° left rotation.Back muscle EMG signals were recorded from surface of paraspinal muscles.The tests performed in the weeks immediately before and after 12-week rehabilitation treatment.The profile and mean power frequency (MPF) of EMG were compared between pre-and post-rehabilitation.EMG profiles showed unchangeable,but the MPF showed significantly increase in post-rehabilitation comparing to pre-rehabilitation.That suggested that the muscle activity strategies could not be modified by rehabilitation,but the rehabilitation would increase the threshold of fatigue and reduce the possible muscle pain in back paraspinal muscles.展开更多
Electric vehicles have been rapidly developing worldwide due to the use of new energy.However,at the same time,serious traffic accidents caused by driver fatigue in emergency situations have also drawn widespread atte...Electric vehicles have been rapidly developing worldwide due to the use of new energy.However,at the same time,serious traffic accidents caused by driver fatigue in emergency situations have also drawn widespread attention.The lack of datasets in real vehicle test environments has always been a bottleneck in the research of driver fatigue in electric vehicles.Therefore,this study establishes a dataset from real vehicle test,applies the Bayesian optimization support vector machine(BOA-SVM)algorithm to take features of electromyography(EMG)and electrocardiography(ECG)signals as input and develop an early warning model for driving fatigue detection.Firstly,the driver’s EMG and ECG signals are collected through real vehicle testing experiments and then combined with the driver’s subjective fatigue evaluation scores to establish the dataset.Secondly,the study establishes a driver fatigue early warning model for emergency situations.Time-domain and frequency-domain features are extracted from the EMG signals.Principal component analysis(PCA)is applied for dimensionality reduction of these features.The experimental results show that based on the input of dimensionality reduced EMG features and ECG features,the BOA-SVM algorithm achieved an accuracy of 94.4%in classification.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
文摘BACKGROUND Functional epiphora is a clinical condition which is not due to an anatomic defect.Most studies agree that it involves the action of the orbicularis oculi muscle,particularly its deeper segment(Horner’s muscle),but the exact mechanism is not clear.AIM To evaluate the orbicularis oculi muscle in functional epiphora patients using electromyography(EMG).METHODS A total of 8 Chinese patients(16 eyes)with functional epiphora were enrolled in this study,and ten volunteers(10 eyes)were included as normal controls.Five epiphora patients(five eyes)with facial palsy served as positive controls.Quantitative EMG was performed in the deeper segment of orbicularis oculi muscle.The average duration of each EMG waveform was measured.RESULTS The average duration of EMG waveforms in the normal control group,the functional epiphora group,and the facial palsy group were 6.39±0.73 ms,9.39±1.32 ms and 11.2±1.42 ms,respectively.The duration of EMG waveforms was significantly longer in the functional epiphora group than in the normal control group(P<0.05),and shorter than that in the facial palsy group(P<0.05).CONCLUSION These data indicate the presence of neurogenic orbicularis oculi muscle damage in epiphora patients,which may be the cause of functional epiphora.The etiology of neurogenic damage in the orbicularis oculi muscle requires further investigation.
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.
基金the Special Fund for Basic Scientific Research of Central Colleges,Chang'an University,China(Nos.2014G2320006,2013G3322009,and 2014G1321040)the Key Science and Technology Program of Shaanxi Province,China(No.2014K05-59)
文摘Sports compression garments are common-selected sportswear to improve athletic performance and reduce sports injury. Since they consist of elastic textile that exerts compression and pressure onto the muscle,muscle activation is of interest to sports compression garment manufactures who seek to enhance sports performance through gradient compression garment design.However,there are few scientific investigations to explore this effect of muscle activation to evaluate the performance of sports compression garments during sport activity. In this paper, a systemic experimental protocol was presented to improve the quality of evaluation test under a standardized running test. Then muscle activation with and without wearing sport compression garments to highlight the changes caused by compression garment was investigated. The electromyography( EMG) signal was collected and processed by the proposed method to represent the muscle activation combined with gait analysis of running. As a result,the average muscle activation of gait cycle for the major muscles such as rectus femoris( RF) and gastrocnemius medialis( GM) revealed that they needed to exert more muscle force without wearing garment at certain periods for mid-stand and pre-swing phase within gait cycle. These lower muscle activation levels prolonged activity duration,reduced fatigue,and presented low risk for sport injury.Such an evaluation study therefore would scientifically prove the effect of compression garment and provide information on muscle activation and the ergonomic efficacy of gradient compression garment design.
文摘BACKGROUND Bruxism is a rhythmic masticatory muscle activity that occurs involuntarily in a non-physiologically functional state.There is a lack of research classifying the functional status of masticatory muscles in patients with different mandibular movement types(centric clenching or eccentric grinding)of bruxism.AIM To assess the differences of the masticatory muscle activity in patients with different types of bruxism.METHODS A total of 21 subjects with centric bruxism(CB)and 21 subjects with eccentric bruxism(ECB)were screened from college students according to a questionnaire and their tooth wear features.Sixteen subjects with no bruxism were also recruited.The surface electromyography(EMG)signals of the temporalis anterior(TA)and superficial masseter muscle(MM)were measured in different mandibular positions and during the chewing task.The EMG amplitude and chewing cycle duration parameters were then analyzed.RESULTS The CB group showed fewer muscle maximal motor units,with the MM being more pronounced,a higher proportion of muscle contractions to be recruited for the same load of chewing activity,and a longer chewing cycle.The ECB group showed more TA maximal motor units and higher MM activity on the nonworking side in unilateral chewing.CONCLUSION CB mainly affects the MM,and patients with CB show reduced masticatory muscle contraction efficiency and chewing cycle efficiency.ECB mainly affects the TA,and patients with ECB show enhanced contraction of non-functional lateral muscle bundles.
文摘This study is to investigate the changes of back muscle electromyography (EMG) in occupational low back pain (LBP) patients pre-and post-rehabilitation.20 occupational LBP patients were asked to perform sepcially designed symmetrical and asymmetrical actions,which include"carrying"weights up and down with a 45° left rotation.Back muscle EMG signals were recorded from surface of paraspinal muscles.The tests performed in the weeks immediately before and after 12-week rehabilitation treatment.The profile and mean power frequency (MPF) of EMG were compared between pre-and post-rehabilitation.EMG profiles showed unchangeable,but the MPF showed significantly increase in post-rehabilitation comparing to pre-rehabilitation.That suggested that the muscle activity strategies could not be modified by rehabilitation,but the rehabilitation would increase the threshold of fatigue and reduce the possible muscle pain in back paraspinal muscles.
基金Supported by the Key Research and Development Program of Ningbo(No.2023Z218)the Joint Funds of the National Natural Science Founda-tion of China(No.U21A20121)+1 种基金the National Natural Science Foundation of China(No.51775325)the Young Eastern Scholars Program of Shanghai(No.QD2016033).
文摘Electric vehicles have been rapidly developing worldwide due to the use of new energy.However,at the same time,serious traffic accidents caused by driver fatigue in emergency situations have also drawn widespread attention.The lack of datasets in real vehicle test environments has always been a bottleneck in the research of driver fatigue in electric vehicles.Therefore,this study establishes a dataset from real vehicle test,applies the Bayesian optimization support vector machine(BOA-SVM)algorithm to take features of electromyography(EMG)and electrocardiography(ECG)signals as input and develop an early warning model for driving fatigue detection.Firstly,the driver’s EMG and ECG signals are collected through real vehicle testing experiments and then combined with the driver’s subjective fatigue evaluation scores to establish the dataset.Secondly,the study establishes a driver fatigue early warning model for emergency situations.Time-domain and frequency-domain features are extracted from the EMG signals.Principal component analysis(PCA)is applied for dimensionality reduction of these features.The experimental results show that based on the input of dimensionality reduced EMG features and ECG features,the BOA-SVM algorithm achieved an accuracy of 94.4%in classification.
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.
