Electromyographic Studies Of Suprahyoid Muscles And Infrahyoid Muscles In Dogs

Objective:To study synchronous electromyograhic features of suprahyoid muscles(anterior digastric muscle,AD,posterior digastric muscle,PD,stylohyoid muscle,STH,mylohyoid muscle,MH,and geniohyoid muscle,GH),infrahyoid muscles(sternohyoid muscle,SH,sternothyoid muscle,ST,thyrohyoid muscle,TH) and intrinsic laryngeal muscles(lateral cricoarytenoid muscle,LCA,and posterior cricoarytenoid muscle,PCA)under the circumstances of breath,swallowing and phonation.Select the exterior laryngeal muscles whose myoelectric feathers are similar to LCA or PCA.Method:synchronous electromyograhic features of 13 dogs were observed under the circumstances of breath,swallowing and phonation,including of time taken in advance of myoelectricity,peak amplitude,contraction activity lasting, amplitude and duration.Compare synchronous electromyograhic features of suprahyoid muscles to infrahyoid muscles in 5 dogs.The relation of myoelectricity of laryngeal muscle and laryngeal function was analyzed as well.Result:1.AD,PD,STH,MH,GH,SH,ST and PCA discharge during inspiratory phase,while TH and LCA discharge during expiratory phase.All the above muscles have a reinforced discharge in condition of deep breath.During the inspiratory phase GH is synchronized with PCA,and the wave shape, amplitude,duration and intensity of myoelectricity of GH are similar to those of PCA respectively,and TH is synchronized with LCA during the expiratory phase.2.during swallowing,AD,PD,STH,MH,GH,TH and LCA show intensive synchronous discharge.The myoelectricity of PCA is suppressed while myopotential can be detected during intermission.SH and ST show obsolete myoelectricity activities.During swallowing MH,GH and TH are synchronized with LCA;and the wave shape,amplitude,duration and intensity of MH,GH and TH are similar to those of LCA respectively.3.during phonation,AD,PD,SH,ST,TH,LCA and PCA show an intensive synchronous discharge,while emergence time of PCA is later.GH and STH show obsolete myoelectricity activities.During phonation MH and TH are synchronized with LCA;and the wave shape,amplitude,duration and intensity of MH and TH are similar to those of LCA respectively.Conclusion:1.During phonation MH and TH are synchronized with LCA;and the wave shape,amplitude,duration and intensity of myoelectricity of MH and TH are similar to those of LCA respectively.MH and TH can be chosen as the backup muscle for the reestablishment of glottic adducent function.2.During the inspiratory phase GH and ST are synchronized with PCA, and the wave shape,amplitude,duration and intensity of myoelectricity of GH and ST are similar to those of PCA respectively,so GH and STcan be chosen as the backup muscles for the reestablishment of vocal cord abducens function.3.During the expiratory phase TH is synchronized with LCA;and the wave shape,amplitude,duration and intensity of myoelectricity of TH are similar to those of LCA respectively.TH can be chosen as the backup muscle for the reestablishment of glottic adducent function.4.During swallowing MH and TH are synchronized with LCA;and the wave shape,amplitude,duration and intensity of myoelectricity of MH and TH are similar to those of LCA respectively.MH and TH can be chosen as the backup muscle for the reestablishment of glottic adducent function.