Suprahyoid Muscle Activity Research Articles

Reliability and Validity of Measuring the Strength of the Chin-Tuck Maneuver in Community-Dwelling Older Adults as a Means of Evaluating Swallowing-Related Muscle Strength

Background: The chin-tuck maneuver has been suggested to increase suprahyoid muscle activation, but a method to measure the strength of the chin-tuck maneuver has not been established. We developed a method to measure the strength of the chin-tuck maneuver (chin-tuck strength) and examined the reliability and validity of chin-tuck-strength measurement in community-dwelling older adults. Participants and Methods: The participants were 233 older adults aged ≥65 years without dysphagia or physical disability. Chin-tuck strength was measured twice consecutively using the developed device, and reproducibility was analyzed using intraclass correlation coefficients (ICCs). In addition, maximum tongue pressure, oral diadochokinesis, grip strength, knee extension strength, and the timed up and go test (TUGT) were measured as indices of swallowing-related muscle function and appendicular muscle function. The associations of chin-tuck strength with swallowing-related muscle function and appendicular muscle function were analyzed statistically. Results: The ICCs for chin-tuck strength were 0.82 (95% confidence interval [CI]: 0.73–0.88) in males and 0.87 (95% CI: 0.70–0.93) in females. Chin-tuck strength was significantly associated with maximum tongue pressure, grip strength, knee extension strength, and TUGT. Conclusions: This study suggests that chin-tuck strength is a reliable and valid assessment of swallowing-related muscle strength.

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.

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.

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.

The effect of craniocervical flexors endurance training on suprahyoid muscle activation in healthy adults: A randomised controlled trial.

Cervical posture affects swallowing function through contractile and non-contractile structures. Craniocervical flexor endurance training (CCFET), which focuses on the activation of deep cervical muscles, is used to ensure cervical posture stability. The aim of this study was to investigate the effect of CCFET on the suprahyoid muscles (SH), which play an important role in swallowing function. Eighty healthy individuals (52 female and 28 male, mean age 21.77 ± 1.81 years) were recruited and randomly assigned to groups that underwent either deep cervical flexor (DCF) training with a pressure biofeedback unit (CCFET group, n = 41) or no intervention (control group, n = 39). The intervention was applied for 4 weeks (five sessions per week). Static endurance and activation of DCF muscles (Craniocervical Flexion Test, CCFT), tragus-wall distance (TWD) for forward head posture and surface electromyographic (sEMG) activation of suprahyoid muscles were evaluated. The endurance and activation of the DCF muscles were significantly increased in the CCFET group (p = <.001). In the CCFET group, TWD significantly lower than the control group (p = <.001) Peak SH amplitude and mean SH amplitude were lower in the CCFET group compared to the control group (p = .013, p = .003). The study shows that 4 weeks of CCFET reduced SH muscle activation, allowing the same work to be done with fewer motor units. CCFET can be included in rehabilitation programs as an additional method that has an effect on the muscles involved in swallowing by providing cervical motor control.

Tongue pressure and maxillofacial muscle activities during swallowing in patients with mandibular prognathism.

Coordination among lip, cheek and tongue movements during swallowing in patients with mandibular prognathism remains unclear. This study aimed to identify the temporal sequences of tongue pressure and maxillofacial muscle activities during swallowing in patients with mandibular prognathism and compared characteristics with those of healthy volunteers. Seven patients with mandibular prognathism (mandibular prognathism group) and 25 healthy volunteers with individual normal occlusion (control group) were recruited. Tongue pressures and masseter, orbicularis oris, mentalis and supra- and infrahyoid muscle activities while swallowing gel were measured simultaneously using a sensor sheet system with five measurement points and surface electromyography, respectively. Onset time, offset time and durations of tongue pressure and muscle activities were analysed. In the mandibular prognathism group, tongue pressure was often produced first in more peripheral parts of the palate. Offset of tongue pressure in the posteromedian and peripheral parts of the palate and maxillofacial muscle activities except for orbicularis oris were delayed. Duration of tongue pressure in the anteromedian part of the palate was significantly shorter and durations of masseter, mentalis and suprahyoid muscle activities were significantly longer. Times to onset of orbicularis oris and suprahyoid muscle activities based on first onset of tongue pressure were significantly shorter. These results suggest that patients with mandibular prognathism may exhibit specific patterns of tongue pressure production and maxillofacial muscle activities during swallowing.

Formulation of Functional Liquid Diets Under IDDSI Levels 0 to 2 for Dysphagia Patients: Physico-Chemical, Sensory, Antioxidant and Electromyographic Oral Processing Analyses.

Dysphagia is a significant health concern especially amongst the old age population. It is an ailment brought on by the weakening of the swallowing muscles. To reduce the risk of choking in dysphagia patients, the food is usually diluted to suit their swallowing ability. But dilution results in reducing the nutritional density of the foods thus causing undernutrition and malnutrition in patients. In this study, functional liquid diets were formulated under International Dysphagia Diet Standardization Initiative (IDDSI) levels 0-2. The developed diets were analysed for their proximate composition, colour, antioxidant and sensory properties. Antioxidant activities were determined using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and total phenolic content (TPC) methods. The highest ABTS+ value was observed in pumpkin puree (level-2) i.e. 98.59%. Black carrot juice (level-1) showed the highest DPPH free radical scavenging activity and FRAP value viz. 88.43% and 689.33µM TE/g, respectively. Electromyography (EMG) is an upcoming technique of food texture evaluation which provides real-time information about food oral processing. In this study, an EMG was conducted to measure the myoelectrical activity of human suprahyoid and masseter muscles by placing electrodes on the skin's surface during the oral processing of liquid. The EMG parameters correlated significantly with viscosity, ease of swallowing and IDDSI levels of the formulated diets. Hence EMG can be used as a tool for design and development of textured-modified diets for dysphagia patients. The sensory scores of formulated diets in this study were high indicating that these liquid diets may be incorporated into the diet plans of dysphagia patients.

Predicting Dysphonia by Measuring Surface Electromyographic Activity of the Supralaryngeal Muscles.

This study set out to investigate whether individuals with dysphonia, as determined by either self-assessment or clinician-based auditory-perceptual judgment, exhibited differences in perilaryngeal muscle activities using surface electromyography (sEMG) during various phonatory tasks. Additionally, the study aimed to assess the effectiveness of sEMG in identifying dysphonic cases. A total of 77 adults (44 women, 33 men, Mage = 30.4 years) participated in this study, with dysphonic cases identified separately using either a 10-item Voice Handicap Index (VHI-10) or clinician-based auditory-perceptual voice quality (APVQ) evaluation. sEMG activities were measured from the areas of suprahyoid and sternocleidomastoid muscles during prolonged vowel /i/ phonations at different pitch and loudness levels. Normalized root-mean-square value against the maximal voluntary contraction (RMS %MVC) of the sEMG signals was obtained for each phonation and compared between subject groups and across phonatory tasks. Additionally, binary logistic regression analysis was performed to determine how the sEMG measures could predict the VHI-10-based or APVQ-based dysphonic cases. Participants who scored above the criteria on either the VHI-10 (n = 29) or APVQ judgment (n = 17) exhibited significantly higher RMS %MVC in the right suprahyoid muscles compared to the corresponding control groups. Although the RMS %MVC value from the right suprahyoid muscles alone was not a significant predictor of self-evaluated dysphonic cases, a combination of the RMS %MVC values from both the right and left suprahyoid muscles significantly predicted APVQ-based dysphonic cases with a 69.66% fair level. This study found that individuals with dysphonia, as determined by either self-assessment or APVQ judgment, displayed more imbalanced suprahyoid muscle activities in voice production compared to nondysphonic groups. The combination of the sEMG measures from both left and right suprahyoid muscles showed potential as a predictor of dysphonia with a fair level of confidence. https://doi.org/10.23641/asha.25112804.

Effect of Visual Biofeedback Obtained Using the Iowa Oral Performance Instrument on the Suprahyoid Muscle Activation Level During Effortful Swallowing Maneuver.

Effortful swallowing (ES) is a maneuver prescribed for patients who experience pharyngeal residues after swallowing owing to weakness of the tongue and pharyngeal constrictor muscles. ES can increase the pharyngeal contraction force by intentionally increasing the degree of effort during swallowing. However, the effect is limited as the nature of swallowing makes it difficult to maintain a constant high-effort level. The aim of this study was to assess the effect of visual feedback, delivered by the Iowa Oral Performance Instrument (IOPI), a tongue pressure measurement device on ES maneuver effort. Overall, 34 healthy adults performed five sets of ten ES, once every 10s. The ES maneuver was conducted under two conditions, ES with and without IOPI biofeedback in a crossover design. IOPI biofeedback was provided at 80% of the maximum posterior oral tongue pressure. The suprahyoid muscle activation level was assessed using surface electromyography during the ES maneuver. The mean suprahyoid muscle activation levels in all sets for which IOPI biofeedback was provided were significantly higher than those during ES maneuver without biofeedback (p < 0.05). IOPI biofeedback can help maintain the ES maneuver target effort, utilizing a constantly high swallowing pressure potentially promoting better pharyngeal pressures and muscle strength.

Changes In the Activation of Supra-hyoid Muscles and Heart Rate of College Students During Food Intake According to Watching Mukbang

Objectives: Watching mukbang contributes to changes in eating habits and related behaviors. In this study, we aimed to analyze the changes in supra-hyoid muscles′ activation and heart rate of college students according to watching mukbang. Methods: The study participants were 30 college students. During the watching of mukbang, water, and yogurt were allowed to be consumed, and then the changes in suprahyoid muscles′ activation and heart rate were analyzed. Surface EMG of VatalStim Plus was used to measure the supra-hyoid muscles′ activation and the average, maximum, and minimum values were measured. An Apple Watch measured heart rate and average heart rate was determined. Results: Through watching mukbang, the average and maximum values of the supra-hyoid muscles′ activation showed a statistically significant increase in the case of both food intakes. Conclusions: During food intake, watching mukbang induces changes in the supra-hyoid muscles′ activation. Therefore, the changes in food intake should be considered according to the increase in the supra-hyoid muscles′ activation due to the influence of watching mukbang. Follow-up studies to verify effects on eating behavior and intake should be conducted.

Surface electromyographic (sEMG) activity of the suprahyoid and sternocleidomastoid muscles in pitch and loudness control.

Purpose: This study set out to determine the contributions of the suprahyoid and sternocleidomastoid (SCM) muscles in changing pitch and loudness during phonation among vocally healthy populations. Method: Thirty-nine participants were first recruited, and twenty-nine of them who passed the screening test (Voice Handicap Index [VHI]-10 score ≤11, auditory-perceptual voice rating score ≤2) were finally selected (mean age = 28.2years). All participants were measured for their surface electromyographic (sEMG) activity collected from the bilateral suprahyoid and SCM muscles when producing the vowel /a/, /i/, and /u/ in natural (baseline) and at different pitch (+3, +6, -3, -6 semitones) and loudness (+5, +10, -5dB) levels. Linear mixed-effects models were performed to determine the influencing factors on the root-mean-square percentage of maximal voluntary contraction (RMS %MVC) value of the sEMG signals. Results: Compared with the baseline, a significant decrease of RMS %MVC was found in the suprahyoid muscles during overall phonations of lower pitches (-3 and -6 semitones) and loudness (-5dB). However, no significant change was detected when producing speech at higher pitch (+3 and +6 semitones) and loudness (+5 and +10dB) levels. Among the three vowels, /i/ demonstrated significantly higher RMS %MVC than those of /a/ and /u/. The SCM muscles, however, did not show any significant change in the RMS %MVC values among different vowels in relation to the pitch and loudness changes. When the muscles were compared across the two sides, significantly higher RMS %MVC was found in the right side of the suprahyoid (in pitch and loudness control) and SCM (in pitch control) when compared to the left side. Conclusions: The suprahyoid muscle activities were significantly decreased when producing lower pitches and intensities compared to the natural baselines. The production of sustained /i/ required significantly more suprahyoid muscle activities than those of /a/ and /u/. The SCM muscles did not show much sEMG activity in any of the pitch and loudness levels, which could be used potentially as the calibration or normalization of peri-laryngeal sEMG measurement. The findings also showed a tendency for bilateral asymmetry in the use of suprahyoid and SCM muscles.

Functional evaluation of jaw and suprahyoid muscle activities during chewing.

It has not yet been clarified how the type of the chewing task affects related muscle activity and how the suprahyoid muscles contribute to masticatory function in humans. This study aimed to investigate the difference in the suprahyoid muscle activity between the freely and unilaterally chewing tasks and between the working and non-working sides during chewing. Twenty healthy volunteers were instructed to chew peanuts and two different types of rice crackers in two ways: freely and unilaterally while surface electromyograms of the masseter and suprahyoid muscles were recorded. The chewing duration, number of chewing cycles and chewing rate were compared between the tasks. Furthermore, the masseter and suprahyoid muscle activities per chewing cycle were compared between the sides. The chewing duration was significantly longer, and the chewing rate was significantly higher during unilaterally chewing than freely chewing. The chewing duration differed significantly among the different foods; the harder the food, the longer the duration. Chewing rate and suprahyoid activity were significantly higher during soft rice cracker chewing. Masseter activity was higher on the chewing side than on the non-chewing side while there was no difference in suprahyoid activity between the sides. The current results demonstrate a difference in the masticatory efficacy between the chewing tasks and a functional role of the suprahyoid muscles during chewing, which does not differ between the chewing and non-chewing sides.

The effects of tongue elevation using a weighted plastic bottle on the tongue pressure and activity of suprahyoid muscles.

A rise in tongue pressure coincides with an increase in the suprahyoid muscle activity. The aim was to investigate the effects of holding a weighted plastic bottle on tongue pressure and the suprahyoid muscle activity. Eighteen participants (8 men and 10 women; mean age 42 ± 16 years) participated in this study. All participants had no history of speech, language, hearing or swallowing disorders and no tooth loss, and they did not require dentures. Healthy participants held gauzes connected with a plastic bottle with increasing resistive loads of 0g, 250 g, 500 g and 750 g, between their palate and tongue. The maximum tongue pressure and average tongue pressure were measured during a 5s hold. The average tongue pressure was defined as the mean tongue pressure data in each task. The suprahyoid muscle activity was measured using the electromyogram (EMG). The root mean square of the EMG signals measured while lifting different loads and while performing the head lifting exercises was compared. All variables were examined using the Friedman's test and Wilcoxon signed-rank test. The maximum tongue pressure (p < .05) and average tongue pressure values (p < .05) increased gradually in the anterior-median region with increasing resistive loads, and the root mean square amplitudes for 250 g, 500 g and 750 g were not significant compared with head lifting exercises. These results indicated that plastic bottle holding could be a potential strength training tool for the tongue and the suprahyoid muscles.

Strength and morphology of a suprahyoid muscle and their relationship to forward head posture in healthy older adults.

Forward head posture, an abnormality in head and trunk positioning, adversely affects suprahyoid muscle activity. Jaw-opening force, which reflects suprahyoid muscle strength, is a useful index of dysphagia. However, the relationship between forward head posture and strength and morphology of suprahyoid muscles remains unclear. This study aims to clarify the relationship between forward head posture, jaw-opening force and morphology of suprahyoid muscles. During October 2018, we enrolled older adults aged ≥65 years. The craniovertebral angle was measured, and an angle <49° was defined as forward head posture. Jaw-opening force was also measured. The geniohyoid muscle (GHM) was selected to represent the suprahyoid muscles, and its cross-sectional area and length were measured using ultrasonography. Sarcopenia was also determined based on the criteria of the 2019 Asian Working Group for Sarcopenia. Multiple regression analyses were conducted to determine the association between morphological characteristics of the suprahyoid muscle and jaw-opening force as well as the association between the former and forward head posture. Data of 87 participants were analyzed. Sex, cross-sectional area and length of the GHM, and sarcopenia were significantly associated with jaw-opening force. In addition, sex and forward head posture were significantly associated with the length of the GHM. Our study demonstrated that an overextended length of suprahyoid muscles mediates the relationship between forward head posture and jaw-opening force. Forward head posture is easily visualized and can be a useful indicator of decline in suprahyoid muscle strength. Geriatr Gerontol Int 2022; 22: 779-784.

Effectiveness of Chin Tuck Against Resistance (CTAR) Exercise upon Feeding Performance of patients with Cerebrovascular Accident

Stroke is a medical emergency. It is the second leading cause of death worldwide. Dysphagia presents in approximately 55% of all acute stroke patients admitted to hospital. In order to improve the overall outcome after stroke it is essential that the feeding performance need to be improved through Chin Tuck Against Resistance (CTAR) Exercise. This study was aimed to evaluate the effectiveness of Chin Tuck Against Resistance (CTAR) exercise in improvement of feeding performance among patients with CVA. Methods: A Quasi- experimental study was conducted after obtaining ethical clearance and setting permission. The data was collected after obtaining consent from 70 CVA patients, who were selected by consecutive sampling technique. Pretest data was collected from both the groups by predetermined and pretested tools such as demographic variable Performa, clinical variable proforma and FOIS (Functional Oral Intake scale) through interview and observation method. Chin Tuck Against Resistance Exercise was administered for 8 consecutive days, 3 times a day for experimental group of patients with CVA. Posttest assessment of feeding performance in both the groups was conducted after one week of intervention. Results: Study findings revealed that there was no significant different in mean pretest score of feeding performance in the control group (M=2.63, S.D+1.12) and experimental group (M=2.05, S.D+1.28) with ‘t’ value 1.95(p&gt;0.05).Whereas, there was a significant difference in the posttest scores of feeding performance in the experimental group (M=6.4,S.D+3.25) which was higher than control group (M=3.13,S.D+1.23) with ‘t’ value of 18.22, (p&lt;0.001). It can be attributed to the effectiveness of CTAR exercise to improve suprahyoid muscle activity and tongue pressure Conclusion: Chin Tuck Against Resistance Exercise was helpful in improving the feeding performance upon patients with CVA dysphagia.

Correlation between cervical auscultation and electromyography in the pharyngeal phase of swallowing

Objective: Correlate the acoustic data of cervical auscultation to the electrical activity of the muscles involved in the pharyngeal phase of swallowing. Methods: This is an observational, cross-sectional study involving a quantitative approach and was approved on January by CEP/UFSCPA (number 1.389.050). All participants of the study signed an informed consent form. The pharyngeal phase of swallowing was assessed by employing auscultation and surface electromyography. Individuals ingested 90 ml of water. The auscultation data were transferred to DeglutiSom® software, the duration and amplitude of electromyographic activity was measured during swallowing using a Miotec® surface electromyography device. The level of significance adopted was 5%. Results: Fifty-seven women participated in this study. The average age was 23.4 years on average. It must be highlighted that the greater the average peak frequency of auscultation, lower was the average peak of the suprahyoid muscle and the greater the intensity, the greater was the peak, as well as the average of the suprahyoid peaks. It was possible to demonstrate that the peak of suprahyoid muscle activity was significantly higher than the peak of infra hyoid muscle activity for swallowing 90 ml of water. Conclusion: The acoustic swallowing parameters in healthy individuals are correlated with the electrical activity of muscles involved in the pharyngeal phase of swallowing.

Possible Impact of Mylohyoid Muscle Architecture on Reduced Hyolaryngeal Elevation

One of the most important problems in swallowing function is the risk of inadequate airway closure and aspiration. Insufficient hyolaryngeal elevation during swallowing is one of the reasons for this risk. Suprahyoid (SH) muscles are fundamental structures responsible for hyolaryngeal elevation. Inadequate activation of SH muscles causes insufficient and reduced hyolaryngeal elevation. Reduced hyolaryngeal elevation causes insufficient opening of the upper esophageal sphincter (UES), leading an increase in the amount of pharyngeal residue and a risk of aspiration. Superior hyolaryngeal excursion during swallowing contributes to airway protection and prevention of aspiration. Anterior hyolaryngeal excursion is related to the UES opening and its crucial for the safe transition of bolus to esophagus without aspiration. Our study hypothesized that the long sarcomere length of mylohyoid muscle could be a contributing or responsible factor to the reduction in the hyolaryngeal elevation. There is no study on the pathophysiology on sarcomere properties of reduced hyolaryngeal elevation. Reduced hyolaryngeal elevation emerges as a symptom that reveals the cause of aspiration. Explaining the potential mechanism of reduction in hyolaryngeal elevation may contribute to the development of new treatment approaches based on architectural features in dysphagia rehabilitation practices. Furthermore, based on our hypothesis, we recommend new therapy approaches that may contribute to reducing the hyolaryngeal elevation.

Effects of Craniocervical Flexion on Suprahyoid and Sternocleidomastoid Muscle Activation in Different Exercises.

This study aims to investigate the effects of craniocervical flexion (CCF) on the activation of suprahyoid and sternocleidomastoid (SCM) muscles in Shaker and Resistant Jaw Opening (RJO) exercises, and to compare the effects of these two exercises on the same muscles with the Chin Tuck Against Resistance (CTAR) exercise. The study recruited a total of 37 healthy participants (20 female and 17 male, mean age: 27.45 ± 7.32years). All participants received craniocervical flexion training with the biofeedback pressure unit (Stabilizer™, Chattanooga Group Inc. USA). Shaker, Shaker with CCF, RJO, RJO with CCF and CTAR exercises were performed and surface electromyographic (sEMG) activations of the suprahyoid and SCM muscles were recorded. In addition, the maximum sEMG activations of suprahyoid and SCM muscles were recorded for the normalization procedure. CCF increased the effect of Shaker exercise on the suprahyoid muscle activation (p < 0.001); but this effect was not seen in RJO exercise (p > 0.05). Suprahyoid muscle activation was lower in Shaker exercise compared to RJO and CTAR exercises (p < 0.016). SCM muscle activation was greater in CTAR exercise compared to Shaker and RJO exercises (p < 0.016). The addition of CCF to the Shaker and RJOE exercises did not affect the ranking among the three exercises for both the suprahyoid and SCM muscles. The result of this study suggest that integration of CCF movement to the Shaker exercise would have a greater therapeutic effect. In addition, RJO exercise can be included in the rehabilitation program as an alternate to CTAR exercise.

Reliability of Ultrasound Examination of Hyoid Bone Displacement Amplitude: A Systematic Review and Meta-Analysis.

In swallowing, the hyoid bone moves up and forward in response to the activation of suprahyoid muscles, opening the upper esophageal sphincter and aiding the airway protection mechanism. This displacement measure has been analyzed with ultrasound images because this method does not expose the patient to radiation, has a good cost-benefit ratio, and is safe for the patient. However, there is no consensus on the reliability of this ultrasound measure. The objective of this study was to analyze the reliability of measuring hyoid bone displacement amplitude in swallowing with ultrasound. The systematic review encompassed five databases (MEDLINE, Scopus, EMBASE, Web of Science, Cochrane Library) and gray literature. There was no limitation of language or year of publication. The search/selection/extraction methodology was conducted by two authors blindly and independently, and differences were solved by a third rater. Three studies met the eligibility criteria: two of them analyzed the reliability in non-dysphagic populations and the other, in dysphagic patients. The transducer was positioned in the submandibular region in all studies. The authors were not clear about the training time to acquire and analyze ultrasound images. The meta-analysis had an interrater reliability of 0.858 (95% CI: 0.744-0.924) and intrarater reliability of 0.968 (95% CI: 0.903-0.990). There was, however, heterogeneity of p = 0.005 for intrarater reliability. Despite good reliability, the heterogeneity reinforces the importance of training and protocol standardization for image acquisition and analysis.

Effects of a tongue training program in Parkinson's disease: Analysis of electrical activity and strength of suprahyoid muscles

ObjectiveTo assess the electrical activity of the suprahyoid muscle and the tongue pressure in a two-wing program of tongue strengthening in individuals with Parkinson's disease (PD). MethodsA pre-post-detraining design study included sixty PD patients assigned to two groups randomly. The experimental group (EG) performed tongue isometric pressure exercises using the Iowa Oral Performance Instrument with an increasing scheme of 5% load weekly and traditional tongue therapy for 8 weeks. The control group (CG) performed only traditional therapy. The electrical activity of suprahyoids was measured using surface electromyography (sEMG) during tongue-to-palate pressure. Four selected domains of the Swallowing Quality of Life Questionnaire (SWAL-QOL) mostly related to tongue strength were considered. ResultsThe experimental group showed increased sEMG values of suprahyoid muscles reaching statistically significant difference at the fourth week of tongue training, while the control did it at the eighth week. Experimental group showed significant improvements in tongue strength (d = 2.128; p = 0.000). Only controls showed detraining effect. Statistically significant difference within groups were found in one and three dimensions of the SWAL-QOL in the CG and EG, respectively. ConclusionAnalysis of electrical activity on suprahyoids muscles provided a better understanding of the changes underlying the outcomes of tongue strength gains obtained through a combined tongue strengthening exercises protocol in PD. Such protocol led not only to increased tongue strength but also to a better perceived swallowing function in PD subjects.