Characteristics Of Submental Muscles Function And Hyoid Bone Movement In Patients With Dysphagia After Stroke

1.BackgroundStroke is one of the main diseases that commonly endanger the health and life of middle-aged and elderly people.Its high morbidity rate,high disability rate and high mortality rate bring heavy economic and psychological burden to the patient’s family and society.Dysphagia is one of the common complications after stroke.Studies have shown that the incidence of post-stroke dysphagia(PSD)is as high as 37%-78%.Dysphagia not only seriously affects the quality of life and increases the burden of family life,but also significantly increases the probability of serious adverse consequences such as aspiration pneumonia,malnutrition,and dehydration.It can delay the recovery of patients,increase the fatality rate and treatment costs,prolong the duration of hospitalization,and even endanger life.Therefore,it is very important to explore the swallowing function characteristics and pathogenesis of dysphagia after stroke.2.ObjectivesTo explore the functional characteristics of electromyographic signals of the submental muscles and the movement of the hyoid during swallowing in PSD patients,as well as the coordination between the function of the submental muscles and the movement of the hyoid bone.3.Subjects and methodsFrom 2020 to 2021,patients with post-stroke dysphagia who were inpatients at Zhujiang Hospital of Southern Medical University were selected for inclusion,and the healthy control group were matched for gender and age.Videofluoroscopic swallowing study(VFSS)and surface electromyography(sEMG)of submental muscles were performed simultaneously in PSD patients and healthy control group while swallowing 5 mL of concentrated fluid.The independent samples-t test was used to compare the differences between the sEMG of the submental muscles and the hyoid bone movement between the PSD group and the healthy control group,and further analyze the correlation between the sEMG activity of the submental muscles and the VFSS parameters.4.Results4.1 SubjectsFinally,15 patients were included in the PSD group,including 10 males and 5 females.Among them,7 cases were cerebral infarction,8 cases were cerebral hemorrhage,the average course of disease was 55.20±34.69 days,and the average age was 57.07±6.54 years.There were 15 healthy controls,7 males and 8 females,with an average age of 56.20±6.65 years.There was no significant difference in gender and age between the two groups.4.2 Quantitative analysis results of VFSS4.2.1 Hyoid kinematics parametersThe hyoid anterior movement(HAM)of the PSD group was 7.09±2.89 mm,and the hyoid anterior movement(HAM)of the healthy control group was 9.64±3.28 mm.There was a statistical difference between the groups(t-test:P value,P=0.032;t value,t(28)=2.253).The hyoid superior movement(HSM)distance in the PSD group was 9.12±4.62mm.The HSM distance in the healthy control group was 12.76±3.22 mm.The difference between groups was statistically significant(t-test:P value,P=0.019;t value,t(28)=2.501).4.2.2 Time parameter analysisBecause the stage transition duration of 2 patients with PSD dysphagia was greater than 3 standard deviations,the abnormal values of these two patients were excluded.The stage transition duration of the PSD group was 0.57±0.22 s and that of the healthy control group was 0.12±0.13 s.The difference was statistically significant in two groups(t-test:P value,P<0.001;t value,t(26)=-6.742).The hyoid bone movement time in the PSD group was 1.56±0.44 s,and hyoid bone movement time of the healthy control group was 1.35±0.19 s.The difference was not statistically significant(t-test:P value,P<0.001;t value,t(28)=-1.768).4.3 sEMG signals results of submental musclesThe root mean square(RMS)value of the submental muscles in the PSD group was 19.83±4.03μV,and the RMS value of the submental muscles in the healthy control group was 24.12±4.51μV.The difference between groups was statistically significant(t-test:P value,P=0.010;t value,t(28)=2.748).The peak electromyography of the healthy control group was 46.39±11.27 μV,and the peak electromyography of the PSD group was 37.04±10.48μV.The difference between groups was statistically significant(t-test:P value,P<0.026;t value,t(28)=2.354).The sEMG activity time of the PSD group was 3.34±0.61 s,and in the healthy control group is 1.8 1±0.25 s,and the difference between groups was statistically significant(t-test:P value,P<0.001;t value,t(28)=-9.038).4.4 Correlation analysis between sEMG signals of submental muscles and hyoid motion parametersThere was a significant positive correlation between the maximum hyoid movement distance and the sEMG peak value of submental muscles in the healthy control group(r=0.660,P=0.014).There was a positive correlation between hyoid bone exercise time and myoelectric activity time of the submental muscles in the healthy control group(r’=0.817,P<0.001).However,there was no correlation between the maximum hyoid distance and the peak value of submental muscles in the PSD group(r=-0.425,P=0.148).There was no correlation between hyoid movement time and myoelectric activity time of the submental muscles in the PSD group(r=-0.289,P=0.296).5.ConclusionsThe submental muscles function and hyoid motor function of PSD patients have different degrees of dysfunction,and the coordination between the submental muscle group and the hyoid movement is changed.The findings may help further explore the pathogenesis of dysphagia after stroke.