Suprahyoid Research Articles

Effects of multi directional chin tuck against resistance exercise on tongue pressure and thickness and suprahyoid muscle activity

The chin tuck against resistance (CTAR) exercise is a therapeutic method developed to activate and strengthen the oropharyngeal muscles related to swallowing in patients experiencing post-stroke dysphagia. However, existing CTAR exercises could be improved by considering the complex characteristics of the suprahyoid muscles. To investigate the efficacy of multidirectional (md-) CTAR on tongue pressure and suprahyoid muscle activity in older adults. Thirty-four older adults were enrolled and randomly assigned to two groups (n = 17/group). Group 1 performed md-CTAR exercises in the left and right diagonal and vertical directions, using the prototype device developed for this study. In contrast, group 2 performed only the vertical-directional (vd-) CTAR exercise using the same device as group 1. Both groups performed the same exercise for 5 days over 6 weeks. Outcome measures were tongue pressure, tongue thickness, and suprahyoid muscle activity, which were evaluated using the Iowa Oral Performance Instrument, ultrasound, and surface electromyography, respectively. As a results, group 1 exhibited significantly higher maximal tongue pressure, tongue thickness, and suprahyoid muscle activity during swallowing than group 2 (p < .05). In conclusion, This study demonstrated that the md-CTAR exercise was more effective than the vd-CTAR exercise in activating the suprahyoid muscles while promoting greater maximal tongue pressure and thickness in older adults.

Application of Action Observation Therapy in Swallowing Rehabilitation: A Randomised Controlled Study.

Action Observation Therapy (AOT) has emerged as a potential neurorehabilitation therapy to promote motor control for individuals with neurological dysphagia (ND), facilitating neural plasticity through activation of the mirror nervous system. The aim of this study was to investigate the effect of AOT-based dysphagia rehabilitation on suprahyoid (SH) muscle activation, swallowing difficulties, swallowing function, depressive symptom and quality of life in ND patients. Thirty-four participants with ND were randomly allocated to the AOT group (n = 17) or control group (n = 17). All participants underwent a 4-week (5 sessions per week) conventional swallowing therapy. The AOT group watched exercise videos before doing these exercises, and the control group performed the same exercises without the videos. Surface electromyographic (sEMG) activation of suprahyoid muscles, Eating Assessment Tool 10 Turkish Version (T-EAT 10) and Swallowing Ability and Function Evaluation (SAFE) for swallowing difficulties and swallowing function, Swallow Quality of Life Questionnaire (SWAL-QOL) and Beck Depression Inventory (BDI) for quality of life and depressive symptom severity were evaluated. Post-treatment SH amplitude level and T-EAT-10 scores were significantly lower in the AOT group compared to the control group (p = 0.001, p = 0.012). There was a significant improvement in SAFE after treatment in the AOT group (p < 0.05); however, there was no significant difference between the two groups (p > 0.05). Both groups showed similar improvement in quality of life and depression. This study showed that AOT can be a good option for improving the SH muscle activation and dysphagia difficulties in ND patients. ClinicalTrials.gov identifier: NCT05782790.

The activation level of the floor-of-the-mouth muscles is systematically modulated using tongue-pressing and swallowing tasks in healthy elderly

ObjectiveThis study aimed to examine how muscle activity of the floor-of-the-mouth (FOM) muscles changes with different target exercise intensities of 40%, 60%, 80%, and 100% of maximum isometric pressure (MIP) during tongue-pressing and swallowing tasks in healthy elderly. DesignThis prospective, repeated-measures within-participant study included 35 participants (mean age: 75.2 ± 4.8 years, 26 women). Each participant performed 16 tasks using the Iowa Oral Performance Instrument (IOPI) in a randomized order, with two repetitions per task (anterior/posterior tongue × pressing/swallowing task × 40/60/80/100% of the MIP). Furthermore, FOM-muscle activity during the task was simultaneously measured using surface electromyography. Statistical analysis was conducted using repeated-measures analysis of variance (ANOVA). ResultsSignificant differences in FOM-muscle activity were observed across most intensity levels during pressing tasks (p < 0.001), with fewer significant differences noted during swallowing tasks, particularly involving the posterior tongue. A significant correlation was found between tongue pressure of the anterior/posterior tongue and FOM-muscle activation level (p < 0.001 and r = 0.517 and 0.447 for the isometric tongue pressure of the anterior and posterior tongue, respectively; r = 0.370 for the swallowing pressure of the anterior tongue) except for posterior tongue swallowing task. ConclusionsThese findings suggest that healthy elderly can systematically modulate suprahyoid muscle activity using a tongue-pressure-measurement device when performing accuracy training. However, they may require personalized systematic feedback and sufficient practice. The study underscores the potential of the IOPI in swallowing rehabilitation for elderly, while also highlighting the need for further research on patients with dysphagia.

The activity of suprahyoid muscles during sevoflurane-induced gasping in mice

Sevoflurane-induced gasping in mice involves an enormous increase in inspiratory effort, mandibular movement, and a marked decrease in respiratory frequency (fR). We examined differences in breathing patterns and electromyogram activity (EMGSH) of the suprahyoid muscles (SHMs) during eupnea under 3.2 % (1 MAC: minimum alveolar concentration) sevoflurane inhalation and sevoflurane-induced gasping under 6.5 % (2 MAC) sevoflurane inhalation in eight spontaneously breathing, tracheally intubated, adult mice. We found that the phasic EMGSH is obtained only during inspiration in eupnea and gasping and that integrated EMGSH increases more, as a percent of baseline (% baseline) than tidal volume (VT) during gasping (median [interquartile range]; integrated EMGSH: 720 [425–1965] vs. VT: 300 [238–373], P < 0.05). We also found that the onset of EMGSH precedes the start of airflow while maintaining a bell-shaped EMGSH contour, which characterizes the EMG of upper airway dilator (UAD) muscles during eupnea and gasping. Vigorous respiratory-related mandibular movements were never observed during eupnea but were observed in seven of 8 mice during sevoflurane-induced gasping. Our observations indicate that SHMs act as a preferentially activating UAD muscle, contributing to the development of mandibular respiratory movements.

High-density surface electromyography evaluation of the suprahyoid muscles in patients with Parkinson's disease

Background and purposeHigh-density surface electromyography (HD-sEMG) allows non-invasive analysis of motor unit (MU) activity and recruitment. This study examines MU recruitment features as well as action potential using HD-sEMG in the suprahyoid muscles of patients with Parkinson's disease (PD) and assesses alterations caused by cervical percutaneous interferential current stimulation. MethodsElectrical activity of the suprahyoid muscles during tongue elevation was measured using HD-sEMG. Maximum voluntary contraction (MVC) was measured, then the modified entropy, coefficient of variation, correlation coefficient, and root mean square (RMS) were examined. For comparison, HD-sEMG was also conducted on healthy controls. In addition, this study assessed the impact of cervical percutaneous interferential current stimulation on HD-sEMG in patients with PD (Hoehn–Yahr stages 2–4) over 8 weeks. ResultsTwenty-two patients with PD (mean age 71.7 ± 6.0, 7 females) and 14 healthy controls (mean age 74.9 ± 6.1, 7 females) were included. The RMS at 60 % MVC was significantly lower in patients with PD than in healthy controls (p = 0.007). After cervical percutaneous interferential current stimulation, the correlation coefficients at 40 % and 60 % MVC significantly decreased (p = 0.040 and p = 0.048, respectively), and the RMS at 60 % MVC significantly increased (p = 0.035). ConclusionHD-sEMG of the suprahyoid muscles showed characteristic findings in patients with PD and was able to detect subtle changes due to electrical stimulation intervention. Thus, HD-sEMG could be a promising tool for evaluating swallowing-related muscle conditions and interventions.

Virtues of routine suprahyoid release during tracheal resection and anastomosis in patients with post intubation stenosis.

Postintubation tracheal stenosis is the most common cause of benign tracheal stenosis. Surgical treatment is more challenging in long-segment stenosis. Suprahyoid release can increase tracheal length resected without anastomotic tension in patients with post-intubation tracheal stenosis. Its effect on swallowing has not been objectively studied and this article aims to explore its virtues and potential complications in a tertiary center for airway surgery. A prospective cohort study was conducted on forty consecutive patients from June 2020 till December 2023. Patients of both genders had tracheal resection anastomosis surgery with routine suprahyoid muscle release for resected tracheal segment of more than 2.5 cm in length aiming to decrease the anastomotic tension. Within two weeks postoperatively, a video naso-laryngoscope was done on all the patients to detect any vocal cord disorders, then they were examined by video fluoroscopy swallowing study VFSS to detect swallowing problems. Follow up was done for 6 months postoperatively. 40 patients were studied. Twenty-five patients (62.5%) were males. 21 patients (52.5%) had a cricotracheal resection. VFSS was performed on 38 patients (two patients excluded for serious morbidity). Six (15.7%) and four (10.5%) patients had residual semisolid and solid food in the vallecula and pyriform fossa respectively during swallowing. Five patients (13%) out of eight patients with abnormal VFSS had aspiration and dysphagia. Video nasolaryngoscopy was done pre- and post-operatively and showed that 7 patients (17.5%) had unilateral vocal cord paralysis, two of them had the same lesion preoperatively. Two patients developed postoperative anastomotic complications. All symptoms of dysphagia improved within 3 weeks of the procedure and improvement persisted for 6 months. Suprahyoid muscle release had a considerable reversible drawback on the process of swallowing. Its routine use in high-risk patients requiring long segment tracheal resections could be considered.

Tongue brushing enhances the myoelectric activity of the suprahyoid muscles in older adults: a six-week randomized controlled trial

Tongue brushing improves respiratory function in older adults. Considering connection between the respiratory-related and suprahyoid muscles, this study aimed to investigate whether tongue-brushing interventions can improve myoelectric activity during respiration. A six-week randomized controlled trial was conducted in Kitakyushu, Japan, with 50 participants aged ≥ 65 years. The participants were allocated to the intervention (tongue brushing with routine oral hygiene) or control (routine oral hygiene alone) groups. Surface electromyography (sEMG) was used to assess the myoelectric activity of the suprahyoid muscles during inhalation, exhalation, and forced vital capacity (FVC). A survey was conducted at baseline and the end of the follow-up period. Thirty-six participants were recruited for the analysis. The root mean squares (RMS) of sEMG during exhalation increased significantly at the end of the follow-up period compared with that at baseline in the intervention group [48.7 (18.0–177.5) vs. 64.9 (21.6–163.0), p = 0.001], but not in the control group. The generalized linear model revealed that the ratio of change in FVC was correlated with the change in the RMS of sEMG of the suprahyoid muscles during exhalation after adjusting for potential confounders. Tongue brushing enhances the myoelectric activity of the suprahyoid muscle.

MyotonPRO as a new valid tool for measuring cervical muscle tension. A reliability study

Objective The main objective of this study is to test the reliability of a non-invasive objective method for the measurement of biomechanical parameters of cervicofacial muscle groups, with the purpose of diagnosis and evaluation of voice disorders’ treatments, especially focused on muscle tension dysphonia. Study design Prospective study. Methods The device used is a handheld myotonometer (MyotonPRO) that measures biomechanical and viscoelastic properties in superficial soft tissues frequency, stiffness, elasticity, relaxation time and creep. It is used in the field of medicine, sport and research. This pilot study includes 10 subjects, who have been measured in the masseter, sternocleidomastoid, orbicularis oris, semispinalis capitis, suprahyoid, infrahyoid and trapezius muscles on each side. Measurements were performed by 2 evaluators to assess inter-evaluator reliability. Subsequently, one of them repeated the measurements to assess intra-evaluator reliability. Results The results revealed good to excellent inter-rater reliability for the masseter, sternocleidomastoid, trapezius and suprahyoid muscles, with lower ICCs for the stiffness and creep properties. Intra-rater reliability was good to excellent for the masseter, sternocleidomastoid, semispinalis capitis and suprahyoid muscles. The lowest ICCs were found in the stiffness and creep properties. Conclusion The use of a myotonometer to measure the mechanical properties of selected cervical and orofacial muscles is a reliable and reproducible method. Future research is needed to establish an association between the properties of these muscles and their role in voice disorders, as well as to determine whether this tool can aid diagnosis with quantifiable and objectifiable indicators, and for monitoring and treatment efficacy.

Extrinsic Laryngeal Muscle Activity and Vocal Economy in Professionally Trained Voices During Vocal Vibrato

Summary PurposeThe purpose of the present study was to determine the extrinsic laryngeal muscle activity and vocal economy during two different singing conditions (straight-tone singing vs. vibrato singing) over a physiologically relevant singing range. MethodsThirty professional singers or voice coaches participated in the study. The participants sang a sustained /a:/ vowel for approximately 5 seconds, once in straight-tone singing conditions and once more in vibrato. The target pitches were C3, F3, A3, C4, F4, A4, and C5. Surface electromyographic (sEMG) measures were performed in the infrahyoid (IH) muscle region and the suprahyoid (SH) muscle region. Contact quotient (CQ), sound pressure level (SPL), and fundamental frequencies were measured to derive the electroglottographic-based vocal economy parameter quasi-output cost ratio (QOCR). ResultssEMG measures show that IH and SH muscles significantly increased in activity with ascending pitch. IH and SH muscle activity were significantly higher when singing in vibrato than straight-tone. Moreover, SPL also increased with ascending pitch and when sung in vibrato. CQ increased and QOCR decreased as pitch ascended but did not significantly change when sung in vibrato. ConclusionSinging higher pitches were generally associated with higher extrinsic laryngeal muscle activity and lower QOCR values. When comparing the two singing conditions, the extrinsic laryngeal muscle activity was higher during vibrato, implicating that the IH and the SH muscles may contribute to rhythmic pulsations of pitch changes. Although the QOCR value did not show significant differences between the two singing conditions, a significantly high SPL during vibrato may indicate acoustical and physiological advantages while singing in vibrato.

Effect of home-based tongue-strengthening exercise using a portable tool on oropharyngeal muscles in older adults with sarcopenic dysphagia: A randomised controlled study.

Tongue-strengthening exercises may be used at home to strengthen swallowing-related oropharyngeal muscles in community-dwelling older adults with sarcopenic dysphagia; however, evidence of their effectiveness remains unclear. This study aimed to investigate the effects of a home-based tongue-strengthening exercise (hTSE) using portable tool on swallowing-related oropharyngeal muscles in community-dwelling older adults with sarcopenic dysphagia. Forth community-dwelling older adults with sarcopenic dysphagia were enrolled in the study. The participants were randomly assigned to the experimental and control groups. 1-Repetition Maximum (1-RM) of tongue muscle was measured in the experimental group using the Iowa Oral Performance Instrument, and hTSE was performed using a portable tool with an intensity corresponding to approximately 70%-80% of the range based on the 1-RM value (90 times/day, 5 days/week, for 8 weeks). The control group did not perform any tongue exercises. The primary outcome measures were tongue strength and thickness. The secondary outcome measure was suprahyoid muscle strength (digastric and mylohyoid muscles). The experimental group showed significantly greater increases in suprahyoid muscle (mylohyoid and digastric) thickness (p = .01 and .011, d = 1.0 and .55), as well as tongue strength and thickness (p < .001 and .029, d = 2.2 and .6) than the control group. This study confirmed that hTSE using a portable tool is effective in increasing swallowing-related oropharyngeal muscle activity in older adults with sarcopenic dysphagia. Therefore, hTSE is recommended as an inexpensive, safe, and easy-to-use therapy for sarcopenic dysphagia in older adults.

Residual effect of sequential 4-channel neuromuscular electrical stimulation evaluated by high-resolution manometry

BackgroundHigh-resolution manometry (HRM) can quantify swallowing pathophysiology to evaluate the status of the pharynx. Sequential 4-channel neuromuscular electrical stimulation (NMES) was recently developed based on the normal contractile sequences of swallowing-related muscles. This study aimed to examine the effects of sequential 4-channel NMES for compensatory application during swallowing and to observe the residual effects after the application of NMES using HRM.ResultsSequential 4-channel NMES significantly improved the HRM parameters, with respect to the maximal pressure and area of the velopharynx (VP), maximal pressure and area of the mesopharynx (MP), and upper esophageal sphincter (UES) activation and nadir duration. Furthermore, the improvement in the pressure and area variables of the VP and MP showed a tendency to maintain even when measured after NMES, but there are no significant differences.ConclusionsThe present study suggests that the sequential 4-channel NMES application of the suprahyoid and infrahyoid muscles during swallowing improves the pressure, area, and time variables of the oropharynx, as measured by HRM, and it is likely that the effects may persist even after stimulation.Trial Registration Clinicaltrials.gov, registration number: NCT02718963 (initial release: 03/20/2016, actual study completion date: 06/24/2016, last release: 10/20/2020).

Comparison between botulinum toxin type A injection on masseter muscle only and additional injection on anterior belly of digastric muscle in sleep bruxism patients: A clinical trial.

This study aims to evaluate the effects on bite force and muscle thickness of the botulinum toxin (BoNT) injection for patients with sleep bruxism (SB) by comparing injections into the masseter muscle only and both the masseter and the anterior belly of the digastric muscle (ABDM) in a clinical trial. Twelve SB patients received BoNT-A injections using US-guided techniques into the masseter muscle only (Group A), while the remaining 12 SB patients received injections into both the masseter and ABDM (Group B). Bite force and muscle thickness were measured before injection, as well as 1 and 2 months after injection. The bite force and masseter muscle thickness decreased in both Group A and Group B before injection, and at 1 and 2 months after injection. However, there was no significant difference (p > .05, repeated measures analysis of variance) between the two groups, and there was also no significant difference in ABDM thickness (p > .05, repeated measures analysis of variance). This study is the first to assess the short-term effects of BoNT injected into ABDM for SB control. Results show no influence on SB reduction, suggesting the need for further research on BoNT's effectiveness in controlling intense ABDM contractions during sleep and assessing suprahyoid muscle potential impact on rhythmic masticatory muscle activity occurrence.

Effect of carbonation and thickening on voluntary swallow in healthy humans.

Liquid modification is a widely established strategy of treatment for patients with dysphagia. The modification of liquid particularly by thickening or carbonation is a common approach to promote safe swallowing. This study sought to investigate how carbonated and/or thickened water modulates swallowing behaviours during swallowing in healthy young individuals. Thirty-one healthy volunteers (9 men, 22 women; mean age ± standard deviation [SD], 25.7 ± 6.2 years) were instructed to swallow 20 mL of water, carbonated water and carbonated juice with and without added thickening agent. Electromyograms (EMGs) of the suprahyoid (S-hyo) muscles were recorded to evaluate swallowing behaviours. Obtained S-hyo EMG bursts was analysed using the following outcome parameters: onset latency, the time between swallowing que to onset of EMG burst; rising time and falling time, defined as the time between onset and peak, and between peak and offset, respectively; duration, defined as the time between onset and offset of EMG burst; and area integral value under the waveform. Effects of thickening demonstrated the extended onset latency, EMG burst duration including falling time and the larger area of EMG in thickened liquid compared to thin liquid, but there was not much difference between thin and thickened carbonated liquids. Carbonation significantly decreased the duration including falling time for thickened but not for thin liquids. Patients with dysphagia can benefit from use of carbonated or thickened water while the effects on swallowing physiology may differ between carbonation and thickening.

Assessing the oral and suprahyoid muscles in healthy adults using muscle ultrasound to inform the swallowing process: a proof-of-concept study

The oral and suprahyoid muscles are responsible for movements of swallowing. Our study aimed to determine the reproducibility of static and dynamic measurements of these muscles using bedside ultrasound equipment. Forty healthy participants were recruited prospectively. Primary outcomes were evaluation of mass measurements of the anterior bellies of the digastric, mylohyoid, geniohyoid and tongue in B-mode ultrasound. Secondary outcomes were evaluation of geniohyoid muscle layer thickness and function using M-mode. Muscle mass measurements demonstrated little within-participant variability. Coefficient of Variance (CoV) across muscles were: anterior belly digastric (5.0%), mylohyoid (8.7%), geniohyoid (5.0%) and tongue (3.2%). A relationship between sex (r2 = 0.131 p = 0.022) was demonstrated for the geniohyoid muscle, with males having higher transverse Cross Sectional Area (CSA) (14.3 ± 3.6 mm vs. 11.9 ± 2.5 mm, p = 0.002). Tongue size was correlated with weight (r2 = 0.356, p = 0.001), height (r2 = 0.156, p = 0.012) and sex (r2 = 0.196, p = 0.004). Resting thickness of the geniohyoid muscle layer changed with increasing bolus sizes (f = 3.898, p = 0.026). Velocity increased with bolus size (p = < 0.001, F = 8.974). However swallow time and slope distance did not, potentially influenced by higher coefficients of variation. Oral and suprahyoid muscle mass are easily assessed using bedside ultrasound. Ultrasound may provide new information about muscle mass and function during swallowing.

The Characterization of Normal Male and Female Voice from Surface Electromyographic Parameters.

Currently, there is no consensus on the characterization of the human voice. The objective of the present study is to describe the myoelectric behavior of the extrinsic musculature of the larynx in 146 people with normal voice (Spanish speakers), aged between 20 and 50 years old. Different vocal tasks were recorded using a surface electromyograph (SEMG). In all vocal tasks, it was observed that women had higher activation (µV) in the suprahyoid and sternocleidomastoid muscles than men, while men had higher activation in the infrahyoid muscles. SEMG is a valid procedure to help define normal vocal characteristics in the studied population, providing reference values during clinical examination. However, it is necessary to adopt a universal system of assessment tasks and standardized measurement techniques to allow for comparisons with future studies.

SEMG as complementary tool for VFSS: A synchronized study in patients with neurogenic oropharyngeal dysphagia

The neurogenic oropharyngeal dysphagia is a prevalent functional swallowing disorder resulting from neurological causes. The conventional diagnosis involves ionizing radiation in Videofluoroscopy Swallowing Studies (VFSS). Surface electromyography (sEMG) offers a non-invasive alternative by recording muscle activity. This research compares bolus passage timing through anatomical structures using VFSS and sEMG-related activation times. Fifty confirmed oropharyngeal dysphagia patients underwent synchronized VFSS and sEMG, evaluating muscle groups during cracker and fluid ingestion. sEMG revealed activation patterns in masseters, suprahyoid, and infrahyoid muscles, occurring before bolus passage through the mandibular line and concluding near the upper esophageal sphincter complex. sEMG identified differences in dysphagia severity (EAT-10 score), age, and diagnosis, contrasting VFSS results. Results indicate potential complementarity between sEMG and VFSS for dysphagia screening, diagnosis, and monitoring.

Reliability of Measuring Geniohyoid Cross-Sectional Area with B-Mode Ultrasound.

B-mode ultrasound is a safe noninvasive procedure that has been used to characterize aspects of the oropharyngeal swallow. The submental suprahyoid muscles are often investigated with ultrasound because of their contributions to hyolaryngeal elevation. There are several techniques for positioning the ultrasound transducer in the coronal plane, however, there is limited research on how reliability of measurement of the cross-sectional area (CSA) of the geniohyoid differs across transducer placement technique. This study examined three methods of transducer placement in the coronal plane by two examiners to determine the reliability of measurement of CSA of the geniohyoid muscle. Forty healthy adults participated in the study. Each participant's geniohyoid muscles were imaged using B-mode ultrasound under three transducer placement conditions in the coronal plane by two examiners. Geniohyoid CSA was measured from each ultrasound image. A three-way mixed-methods ANOVA was used to determine whether there were significant differences in geniohyoid CSA among transducer position conditions, trials, and examiners. There were significant differences among the transducer placement conditions, indicating that each condition was measuring a different portion of the muscle. There were no significant differences among repeated trials nor between examiners within each method of transducer placement. All three conditions of transducer placement were reliable at measuring geniohyoid CSA across trials and examiners. This study emphasizes the need for consistency of placement, whichever method is selected. It also highlights the need for researchers to provide a precise description of methods for positioning the transducer so that placement is reproducible.

Determinated area (DA) treatment goal when treating malocclusions with jaw functional orthopedics (JFO): Contribution to scientific evidence

One of the goals of malocclusion treatment with Jaw Functional Orthopedics (JFO) is to obtain touch of the inferior incisors against the superior incisors in Determinate Area (DA). It is postulated that this touch would bring better stimuli and consequently faster results. Surface electromyographic study of the muscles was performed in Masseter, Temporal and suprahyoid muscles bilaterally from 159 patients undergoing malocclusion treatment with functional orthopedic appliances (FOA). To record muscle electric activity were used a conditioning signal module from Lynx Electronics Ltda with 8 channels, model EMG1000; software AqDAnalysis 4,18 from Lynx Electronics Ltda.; Software Lynx BioInspector 1,8r; passive surface electrodes (Ag/AgCl) from Noraxon Dual Electrodes (USA); dischargeable reference electrodes Kendall Meditrace (Ag/AgCl) – Canada. Frequency calibration was 2000 Hz, with 2048 sample by channel and time 1,024 seconds, and filters regulation was 20 Hz and 1000 Hz. The results found prove that there is a better electromyographic activity (bilaterally balanced) of the studied muscles when there is touch on DA. Conclusion. Touch in DA improves the neuromuscular response of patients treated with JFO. sEMG is a trustable tool to analyze masticatory muscles function for Diagnosis, Treatment and evaluation post treatment/gained objective.

Analysis of the suprahyoid muscles during tongue elevation: High-density surface electromyography as a novel tool for swallowing-related muscle assessment.

High-density surface electromyography (HD-sEMG) has enabled non-invasive analysis of motor unit (MU) activity and recruitment, but its application to swallowing-related muscles is limited. We aimed to investigate the utility of HD-sEMG for quantitatively evaluating the MU recruitment characteristics of the suprahyoid muscles during tongue elevation. We measured the sEMG activity of the suprahyoid muscles of healthy participants during tongue elevation using HD-sEMG. Maximum voluntary contraction (MVC) was measured, followed by data collection during sustained and ramp-up tasks to capture suprahyoid muscle activity. Changes in the temporal/spatial MU recruitment patterns within individual suprahyoid muscles were analysed. This study enrolled 16 healthy young adults (mean age: 27.8 ± 5.3 years; eight males and eight females). Increasing muscle force corresponded to a decrease in modified entropy and correlation coefficient and an increase in the coefficient of variation. No significant differences were observed between male and female participants. The results of this study, consistent with those observed in other muscles, such as the vastus lateralis muscle, suggest that HD-sEMG is a valuable and reliable tool for quantitatively evaluating MU recruitment in the suprahyoid muscles. This measurement technique holds promise for novel assessments of swallowing function.

Deglutition dynamics of patients with obstructive sleep apnea.

In the present study, we performed a detailed analysis of deglutitive dynamics during sleep in patients with obstructive sleep apnea (OSA) using a methodology developed by Sato etal. We hypothesized that the frequency of deglutition would decrease with increasing severity of OSA. The aim of this study is to clarify the involvement of deglutitive dynamics during sleep in OSA by investigating the correlations between deglutition and sleep parameters. This study included 30 adult patients with OSA. To analyze deglutition dynamics during sleep, surface electromyography recordings of the suprahyoid and thyrohyoid neck muscles, which are involved in deglutition, were performed simultaneous with conventional polysomnography. The "index of deglutition" was defined as the frequency of deglutition per hour of sleep. We examined correlations between this index and sleep parameters (apnea-hypopnea index [AHI], apnea index, hypopnea index, and lowest blood oxygen saturation). By analyzing the obtained polysomnography and electromyography waveforms, we identified two deglutition patterns with and without respiratory arousal during sleep. We found a significant negative correlation between the index of deglutition in sleep stage 1 and the AHI, with a correlation coefficient of -0.48. (p=0.02). In the current study, we distinguished deglutition during sleep with and without arousal. In addition we discovered a significant negative correlation between the index of deglutition in sleep stage 1 and the AHI. This new finding will provide a platform for future research on OSA in aspiration pneumonia.