A Study Of Surface Electromyography Characteristics In Functional Dysphonia

Functional dysphonia（FD）is defined as vocal disorders without organic lesions in the larynx,manifested as hoarseness,articulatory fatigue,painful articulation,etc.,which may seriously affect the quality of life of patients.Its causative factors and mechanisms of occurrence,physiological and psychological characteristics are not clear.Clinical examination mostly relies on empirical diagnosis,and there is a lack of reliable qualitative and quantitative studies.Therefore,clearer diagnostic indicators are needed as references for clinical assessment,treatment planning and efficacy observation,and surface electromyography（sEMG）characteristics are one of the key references for the diagnosis of functional vocal disorders.In this study,we analyzed the sEMG characteristics of functional dysphonia in a more comprehensive and systematic way,verified the validity of the indexes by classification tests,with the aim of screening sEMG indexes that may be applied to the diagnosis of functional vocal disorders,and providing a reference for further diagnosis of functional dysphonia based on large data sets.In this study,24 patients with functional dysphonia（experimental group）and 15 healthy subjects without voice disorders（control group）were selected and analyzed for 64 sEMG indices of the trapezius,sternocleidomastoid,supraglottis,subglottis,and cricothyroid muscles during 6active events（clearing the throat,shrugging the shoulders,deep breathing,swallowing,turning the head left,and turning the head right）and 8 articulation events（loud /a/,loud /i/,high /a/,high /i/,long /a/,long /i/,loud high /a/,loud high /i/）.Parameters that were significantly different（p<0.05）between the experimental and control groups were statistically analyzed and screened using independent samples t-test,one-way ANOVA.k-NN,logistic regression,SVM,CART were used to verify the classification performance of sEMG indicators.The results of the analysis showed that 64 sEMG parameters that were significantly different between patients with functional dysphonia and healthy subjects in different muscles and tasks were correlated with the muscle recruitment by the task,and showed the EMG characteristic of muscle tension and muscle fatigue,which indicating that the sEMG indicators of different muscles under different tasks are important references for the assessment,diagnosis,and treatment of functional dysphonia:1.sEMG parameters of muscles recruited in phonation tasks in patients with functional dysphonia showed muscle tension and over-recruitment,while muscles recruited in functional activity tasks showed muscle fatigue,muscle weakness and muscle imbalance.2.Vowel /a/ compared to vowel /i/,and long and loud high phonation task compared to loud and high task were more effective for assessment of functional dysphonia.3.The significance（p<0.05）and F value can effectively screen the sEMG diagnostic and assessment indicators of functional dysphonia,which can provide a reference for the index screening and assessment diagnosis of sEMG signal of functional dysphonia.