Physical loads on upper extremity muscles while interacting with virtual objects in an augmented reality context.

Augmented reality (AR) environments are emerging as prominent user interfaces and gathering significant attention. However, the associated physical strain on the users presents a considerable challenge. Within this background, this study explores the impact of movement distance (MD) and target-to-user distance (TTU) on the physical load during drag-and-drop (DND) tasks in an AR environment. To address this objective, a user experiment was conducted utilizing a 5× 5 within-subject design with MD (16, 32, 48, 64, and 80 cm) and TTU (40, 80, 120, 160, and 200 cm) as the variables. Physical load was assessed using normalized electromyography (NEMG) (%MVC) indicators of the upper extremity muscles and the physical item of NASA-Task load index (TLX). The results revealed significant variations in the physical load based on MD and TTU. Specifically, both the NEMG and subjective physical workload values increased with increasing MD. Moreover, NEMG increased with decreasing TTU, whereas the subjective physical workload scores increased with increasing TTU. Interaction effects of MD and TTU on NEMG were also significantly observed. These findings suggest that considering the MD and TTU when developing content for interacting with AR objects in AR environments could potentially alleviate user load.

Changes in acceleration and deceleration factors associated with active gait speed adjustment.

[Purpose] The ability to actively adjust walking speed is fundamental and the factors enabling it should be assessed. The present study aimed to demonstrate how active gait speed is kinematically adjusted. [Participants and Methods] Walking acceleration and deceleration were evaluated in 16 healthy adults using three-axis accelerometers and surface electromyographs. The root mean square (RMS) of each axis in the center-of-gravity acceleration was calculated as an index of gait stability. Electron myograph data were obtained from images captured of the right lower muscles, and the integral value of total muscle activity per gait cycle was calculated. [Results] The RMS of each axis increased during acceleration and decreased during deceleration. The integral values of total activity of the gastrocnemius, biceps femoris, and tibialis anterior muscles increased in acceleration. In contrast, the values increased in the biceps femoris but decreased in other muscles during deceleration. [Conclusion] These results suggest that the specific kinematic mechanisms of each factor regulate the acceleration and deceleration of walking. In addition, these mechanisms and factors indicate how exercise therapy may be used in rehabilitation to improve the ability to adjust walking speed in daily life.

Actual state of the diurnal masseteric electromyogram: Differences between awareness and non-awareness of awake bruxism.

PURPOSE: This study aimed to elucidate the relationship between diurnal masseter muscle activity and awareness of diurnal awake bruxism (d-AB) by conducting a comparative analysis of electromyographic (EMG) data from individuals with and without awareness of diurnal awake bruxism (d-AB), utilizing EMG data gathered from multiple subjects. METHODS: Unilateral masseter electromyography (EMG) recordings were performed during the daytime using an ultraminiature wearable EMG device. A total of 119 participants (59 with awareness of diurnal tooth clenching [d-TC] and 60 without awareness of d-TC) were included. Waveforms longer than 0.25 s with the two amplitude conditions, exceeding twice the baseline and >5% of maximum voluntary clenching, were extracted. In addition, the number of bursts and episodes (groups of bursts), burst duration, and burst peak amplitude were calculated for each participant. RESULTS: There were no significant differences in the EMG parameters between the groups with and without awareness of d-TC. Additionally, the frequency distribution of the number of EMG waveforms exhibited wide ranges and substantial overlap between the two groups. CONCLUSIONS: The variability in the number of bursts and episodes, burst peak amplitude, and burst duration among subjects suggests the need for an objective classification of d-AB severity based on EMG values. The absence of significant differences and large overlap in frequency distributions between the groups with and without awareness of d-TC indicate difficulty in predicting muscle activity solely based on awareness of d-AB.

Effects of facilitatory and inhibitory Kinesio taping on lateral gastrocnemius muscle activity, motor neuron excitability, and countermovement jump height in university athletes from multiple sports: A randomized controlled trial.

Objectives: This study aims to investigate the temporal effects of two Kinesio Taping (KT) techniques on lateral gastrocnemius muscle activity, motor neuron excitability, and countermovement jump height in university athletes from hockey, football, basketball, and volleyball. Additionally, it investigates whether the athletes' playing positions-either attacker or defender-influence these outcomes following the KT application. Methods: Forty-eight subjects were randomly assigned to one of three groups: Group A (n = 16), Group B (n = 16), and Group C (n = 16). All groups were further subdivided into attackers and defenders. Adhesive Kinesio tape was applied to the lateral gastrocnemius using the Y-shaped technique for three days. Facilitatory KT was applied from the origin to the insertion of the lateral gastrocnemius, while inhibitory KT was applied from the insertion to the origin. Motor neuron excitability, electromyographic activity, and countermovement jump height were tested at baseline, as well as after KT application, to evaluate if the dependent variables had changed. One-way ANOVA was used for baseline comparison, and mixed ANOVA was applied to assess post-interventional effects on the outcome measures. Results: Significant group effects for lateral gastrocnemius activation were found, measured using percentage of maximum voluntary isometric contraction (% MVIC) average root mean square (RMS). In motor neuron excitability, maximal M-wave (Mmax) was significantly improved in group comparison. Further, there was also a significant increase in countermovement jump height. There was no significant difference in outcome measures based on playing position (attacker and defender). Conclusion: Both KT techniques effectively influenced the lateral gastrocnemius muscle's activity, motor neuron excitability, and jump height when compared with the control group. Additionally, there is no effect of playing position, specifically attacker or defender, on the examined variables following KT application.

Cerebellar TMS Induces Motor Responses Mediating Modulation of Spinal Excitability: A Literature Review.

Since individuals with cerebellar lesions often exhibit hypotonia, the cerebellum may contribute to the regulation of muscle tone and spinal motoneuron pool excitability. Neurophysiological methods using transcranial magnetic stimulation (TMS) of the cerebellum have been recently proposed for testing the role of the cerebellum in spinal excitability. Under specific conditions, single-pulse TMS administered to the cerebellar hemisphere or vermis elicits a long-latency motor response in the upper or lower limb muscles and facilitates the H-reflex of the soleus muscle, indicating increased excitability of the spinal motoneuron pool. This literature review examined the methods and mechanisms by which cerebellar TMS modulates spinal excitability.

Shoulder Muscle Activity While Swimming in Different Wetsuits and Across Different Paces.

A triathlon wetsuit is an important piece of equipment during the swim portion of the triathlon for the benefits of thermoregulation and additional buoyancy. However, a lack of knowledge exists about whether or not shoulder muscle activity is influenced by wearing a wetsuit. The purpose of this study was to determine if there were changes in shoulder muscle activity during front crawl with four different wetsuit conditions: Full sleeve (FSW), Sleeveless (SLW), Buoyancy shorts (BS), No wetsuit (NWS) in three different subjective swimming paces (slow, medium, and fast). Eight subjects (5 males, 3 females: mean ± SD, age = 39.1 ± 12.5 years; height = 1.8 ± 0.1 m; mass = 74.6 ± 12.9 kg; percent body fat = 19.0 ± 7.8%) completed twelve total swim conditions (4 wetsuits x 3 swimming pace) in a 25-m indoor pool. Muscle activity in anterior deltoid (AD) and posterior deltoid (PD) were measured using a wireless waterproofed electromyography (EMG) system. Stroke rate (SR) was calculated using the time to complete five-stroke cycles. The AD, PD EMG, and SR were compared using ANOVA with repeated measures. None of the dependent variables showed the interaction between wetsuit conditions and swimming paces (p > 0.05). Both AD and PD muscle activity as well as SR were influenced by swimming pace (p < 0.05) but not wetsuit conditions (p > 0.05). In conclusion, shoulder muscle activity and SR were not influenced by types of wetsuits but influenced by swimming pace.

Pelvic floor evaluation in CrossFit® athletes and urinary incontinence: a cross-sectional observational study.

Athletic urinary incontinence is characterized by urinary loss during sports practice. This condition occurs in the case of CrossFit®, a modality based on high intensity training and functional movements, it can also be considered as having a high impact on the pelvic floor. This study aimed to compare the force and the contraction capacity of the pelvic floor musculature and urinary incontinence between female CrossFit® practitioners (AG) and non-practitioners (CG). We performed a cross-sectional observational study in the period from December 2018 and May 2019. Complaints of urinary incontinence was assessed by the International Consultation on Incontinence Questionnaire - Short Form (ICIQ-SF); the functional evaluation of the pelvic floor was performed by digital palpation; resting tone, maximum voluntary contraction, fast contractions and sustained contraction of the pelvic floor muscles was tested by electromyography. The prevalence of urinary incontinence was significantly higher in AG compared with CG (p < .001). Nevertheless, we did not find significant differences between the two groups for functional assessment and electromyographic parameters. The AG presented a prevalence 60% of UI, while CG only 9,5 (p < 0,001). Considering this point, tailored prevention strategies seem mandatory in this population, in order to allow early identification and management of urinary incontinence.

Occupational Therapy Assessment for Upper Limb Rehabilitation: A Multisensor-Based Approach.

Most post-stroke patients experience varying degrees of impairment in upper limb function and fine motor skills. Occupational therapy (OT) with other rehabilitation trainings is beneficial in improving the strength and dexterity of the impaired upper limb. An accurate upper limb assessment should be conducted before prescribing upper limb OT programs. In this paper, we present a novel multisensor method for the assessment of upper limb movements that uses kinematics and physiological sensors to capture the movement of the limbs and the surface electromyogram (sEMG). These sensors are Kinect, inertial measurement unit (IMU), Xsens, and sEMG. The key assessment features of the proposed model are as follows: (1) classification of OT exercises into four classes, (2) evaluation of the quality and completion of the OT exercises, and (3) evaluation of the relationship between upper limb mobility and muscle strength in patients. According to experimental results, the overall accuracy for OT-based motion classification is 82.2%. In addition, the fusing of Kinect and Xsens data reveals that muscle strength is highly correlated with the data with a correlation coefficient (CC) of 0.88. As a result of this research, occupational therapy specialists will be able to provide early support discharge, which could alleviate the problem of the great stress that the healthcare system is experiencing today.

Single bout of vibration-induced hamstrings fatigue reduces quadriceps inhibition and coactivation of knee muscles after anterior cruciate ligament (ACL) reconstruction.

Persistent quadriceps strength deficits in individuals with anterior cruciate ligament reconstruction (ACLr) have been attributed to arthrogenic muscle inhibition (AMI). The purpose of the present study was to investigate the effect of vibration-induced hamstrings fatigue on AMI in patients with ACLr. Eight participants with unilateral ACLr (post-surgery time: M = 46.5, SD = 23.5 months; age: M = 21.4, SD = 1.4 years) and eight individuals with no previous history of knee injury (age: M = 22.5, SD = 2.5 years) were recruited. A fatigue protocol, consisting of 10 min of prolonged local hamstrings vibration, was applied to both the ACLr and control groups. The central activation ratio (CAR) of the quadriceps was measured with a superimposed burst of electrical stimulation, and hamstrings/quadriceps coactivation was assessed using electromyography (EMG) during isometric knee extension exercises, both before and after prolonged local vibration. For the ACLr group, the hamstrings strength, measured by a load cell on a purpose-built chair, was significantly (P = 0.016) reduced about 14.5%, indicating fatigue was actually induced in the hamstrings. At baseline, the ACLr group showed a trend (P = 0.051) toward a lower quadriceps CAR (M = 93.2%, SD = 6.2% versus M = 98.1%, SD = 1.1%) and significantly (P = 0.001) higher hamstrings/quadriceps coactivation (M = 15.1%, SD = 6.2% versus M = 7.5%, SD = 4.0%) during knee extension compared to the control group. The fatigue protocol significantly (P = 0.001) increased quadriceps CAR (from M = 93.2%, SD = 6.2% to M = 97.9%, SD = 2.8%) and significantly (P = 0.006) decreased hamstrings/quadriceps coactivation during knee extension (from M = 15.1%, SD = 6.2% to M = 9.5%, SD = 4.5%) in the ACLr group. In conclusion, vibration-induced hamstrings fatigue can alleviate AMI of the quadriceps in patients with ACLr. This finding has clinical implications in the management of recovery for ACLr patients with quadriceps strength deficits and dysfunction.

Enhancement of spinal reciprocal inhibition depends on the movement speed and range of repetitive passive movement.

Repetitive passive movement (RPM) is a rehabilitation technique that increases spinal reciprocal inhibition (RI) as movement speed increases. However, characterization of the RPM number, frequency and range relative to the afferent impulses of muscle spindles and RI modulation has not been performed. In this study, we attempted to clarify these factors and evaluate their relationship to RI. We used 20 healthy adults for our first experiment (Experiment 1) and 16 healthy adults for our second experiment (Experiment 2). In Experiment 1, the RPM task was performed in the 80°-120° range for the ankle joint for 618 times at 80°/s (80°/s_618 times), 309 times at 160°/s (160°/s_309 times) and 618 times at 160°/s (160°/s_618 times). In Experiment 2, the RPM task focused on two ranges for the ankle joint (80°-100° and 100°-120°) and was performed at 160°/s with a movement time of 10 min. To measure RI, electrical stimulation was used to evoke a conditioning stimulus in the common peroneal nerve and the test stimulus in the tibial nerve. Conditions included the test stimulus only and conditioning stimulation-test stimulation intervals (CTI) of 2 and 20 ms. RI was measured before (Pre); immediately after; and 5, 10, 15 and 20 min after the task. Our findings suggest that the faster the movement speed of the RPM and the wider the movement range, the greater the increase in Ia firing. This may have enhanced RI by activating the inhibitory interneurons of RI.

Effects of repetitive passive movement on ankle joint on spinal reciprocal inhibition.

Repetitive passive movement (RPM) activates afferent Ia fibers. The input of afferent Ia fibers from antagonist muscle may modulate the extent of spinal reciprocal inhibition (RI). However, effects of RPM on RI remain unknown. We aimed to clarify these effects in 20 healthy adults. Four RPM tasks (40°/s, 80°/s, 120°/s, and 160°/s), with the range of ankle joint movement set to 40°, ranging from 10° in dorsiflexion to 30° in plantar flexion, were performed for 10 min. For measuring RI, a deep peroneal nerve as a conditioning stimulus, tibial nerve as a test stimulus, and three condition-test stimulus intervals (CTIs; single, 2 ms, and 20 ms) were used. The stimulation frequency was 0.3 Hz for 36 times (3 stimulation conditions × 12 sets). RI was measured before, immediately after, and 5, 10, 15, and 20 min (Pre, Post 5, 10, 15, and 20, respectively) after the task. The extent of reciprocal Ia inhibition (CTI 2 ms) significantly increased in Post 5 and 10 at RPM speed of ≥ 120°/s. The extent of D1 inhibition (CTI 20 ms) significantly increased in Post 5 and 10 at RPM speed of ≥ 80°/s, and continued to increase until Post 15 at RPM speed of 160°/s. The extent of RI was the highest at RPM speed of 160°/s for both Ia and D1. Therefore, high RPM may increase the extent of reciprocal Ia inhibition and D1 inhibition, suggesting that rapid movements affect RI by increasing the firing frequency from the muscle spindle to afferent Ia fibers.

Intraoperative Triggered Electromyography Recordings from the External Urethral Sphincter Muscles During Spine Surgeries.

INTRODUCTION: Bowel and bladder function are at risk during tumor resection and other surgeries of the conus, cauda equina, and nerve roots. This study demonstrates the ability to acquire triggered electromyography (t-EMG) from the external urethral sphincter (EUS) muscles by utilizing a urethral catheter with an electrode attached. METHODS: A retrospective analysis of neurophysiological monitoring data from two medical centers was performed. Seven intradural tumors and three tethered cord release surgeries that used urethral sphincter electrodes to record t-EMG were included in the analysis. The patients consisted of five females and five males with ages ranging from eight months to 67 years (median: 49 years). Our neuromonitoring paradigm included upper and lower extremity somatosensory evoked potentials (SSEPs) and transcranial electrical motor evoked potentials (TCeMEPs), as well as spontaneous and triggered electromyography (EMG) from the external anal sphincter (EAS), EUS muscles and lower extremity muscles bilaterally. A catheter with urethral electrodes attached was used for recording spontaneous electromyography (s-EMG), t-EMG, and TCeMEPs from the skeletal muscle of the EUS. Train of four (TOF) was also recorded from the abductor hallucis muscle as well for monitoring the level of muscle relaxant. RESULTS: We were able to successfully record t-EMG responses from the EUS muscles in all patients (100%). It is worthy to note that only one patient presented preoperatively with bladder incontinence, urgency, and frequency. Almost immediately in the postoperative phase, the patient's frequency and urgency improved, and the bladder function normalized within two weeks of having the tumor removed. CONCLUSIONS: In this small series, we were able to acquire t-EMG in 100% of patients when recorded from the EUS using a urethral catheter with electrodes built into it. T-EMGs can be attempted in surgeries that put the function of the pelvic floor at risk. More study is needed to establish better statistical methods, better modality efficacy, and a better understanding of intraoperative countermeasures that may be employed when an alert is encountered to prevent impending neurological sequelae.

sEMG-angle estimation using feature engineering techniques for least square support vector machine.

In the practical implementation of control of electromyography (sEMG) driven devices, algorithms should recognize the human's motion from sEMG with fast speed and high accuracy. This study proposes two feature engineering (FE) techniques, namely, feature-vector resampling and time-lag techniques, to improve the accuracy and speed of least square support vector machine (LSSVM) for wrist palmar angle estimation from sEMG feature. The root mean square error and correlation coefficients of LSSVM with FE are 9.50 ± 2.32 degree and 0.971 ± 0.018 respectively. The average training time and average execution time of LSSVM with FE in processing 12600 sEMG points are 0.016 s and 0.053 s respectively. To evaluate the proposed algorithm, its estimation results are compared with those of three other methods, namely, LSSVM, radial basis function (RBF) neural network, and RBF with FE. Experimental results verify that introduction of time-lag into feature vector can greatly improve the estimation accuracy of both RBF and LSSVM; meanwhile the application of feature-vector resampling technique can significantly increase the training and execution speed of RBF neural network and LSSVM. Among different algorithms applied in this study, LSSVM with FE techniques performed best in terms of training and execution speed, as well as estimation accuracy.

Effectiveness of ultrasonography and nerve conduction studies in the diagnosing of carpal tunnel syndrome: clinical trial on accuracy.

BACKGROUND: The aim of this study was to evaluate the effectiveness of two diagnostic tests routinely used for diagnosing carpal tunnel syndrome (CTS)-ultrasonography (US) and nerve conduction studies (NCS)-by comparing their accuracy based on surgical results, with the remission of paresthesia as the reference standard. METHODS: We enrolled 115 patients, all of the female gender with a high probability of a clinical diagnosis of CTS. All patients underwent US and NCS for a diagnosis and subsequent surgical treatment. As a primary outcome, the accuracy of the US and NCS diagnoses was measured by comparing their diagnoses compared with those determined by the surgical outcomes. Their accuracy was secondarily evaluated based on before and after scores of the Boston Carpal Tunnel Questionnaire (BCTQ). RESULTS: Overall, 104 patients (90.4%) were diagnosed with CTS by the surgical reference standard, 97 (84.3%) by NCS, and 90 (78.3%) by US. The concordance of NCS and surgical treatment (p < 0.001; kappa = 0.648) was superior to that of US and surgical treatment (p < 0.001; kappa = 0.423). The sensitivity and specificity of US and NCS were similar (p = 1.000 and p = 0.152, respectively: McNemar's test). The BCTQ scores were lower after surgery in patients diagnosed by both US and NCS (p < 0.001and p < 0.001, respectively: analysis of variance). CONCLUSIONS: US and NCS effectively diagnosed CTS with good sensitivity but were not effective enough to rule out a suspicion of CTS. TRIAL REGISTRATION: This study was registered at September, 10 th, 2015, and the registration number was NCT02553811 .

Effects of Reciprocal Ia Inhibition on Contraction Intensity of Co-contraction.

Introduction: Excessive co-contraction interferes with smooth joint movement. One mechanism is the failure of reciprocal inhibition against antagonists during joint movement. Reciprocal inhibition has been investigated using joint torque as an index of intensity during co-contraction. However, contraction intensity as an index of co-contraction intensity has not been investigated. In this study, we aimed to evaluate the influence of changes in contraction intensity during co-contraction on reciprocal inhibition. Methods: We established eight stimulus conditions in 20 healthy adult males to investigate the influence of changes in contraction intensity during co-contraction on reciprocal inhibition. These stimulus conditions comprised a conditioning stimulus-test stimulation interval (C-T interval) of -2, 0, 1, 2, 3, 4, or 5 ms plus a test stimulus without a conditioning stimulus (single). Co-contraction of the tibialis anterior and soleus muscles at the same as contraction intensity was examined at rest and at 5, 15, and 30% maximal voluntary contraction (MVC). Results: At 5 and 15% MVC in the co-contraction task, the H-reflex amplitude was significantly decreased compared with single stimulation at a 2-ms C-T interval. At 30% MVC, there was no significant difference compared with single stimulation at a 2-ms C-T interval. At a 5-ms C-T interval, the H-reflex amplitude at 30% MVC was significantly reduced compared with that at rest. Discussion: The findings indicated that during co-contraction, reciprocal Ia inhibition worked at 5 and 15% MVC. Contrary inhibition of reciprocal Ia inhibition did not apparently work at 30% MVC, and presynaptic inhibition (D1 inhibition) might work.

Efeito da terapia vocal associada ao biofeedback eletromiográfico em mulheres com disfonia comportamental: ensaio clínico randomizado, controlado e cego / Effect of vocal therapy associated with electromyographic biofeedback in women with behavioral dysphonia: randomized controlled blinded clinical trial

Introdução: as disfonias podem acometer o nível respiratório, glótico e ressonantal/articulatório, limitar a eficiência da comunicação e gerar prejuízos na qualidade de vida. Quando a etiologia da disfonia está relacionada ao uso vocal incorreto, elas são classificadas como comportamentais. Apesar da literatura mostrar a efetividade de alguns métodos e programas de reabilitação vocal, poucos exploram a autopercepção corporal e a participação da musculatura corporal no quadro da disfonia. A fim de melhorar essas questões, a literatura propôs o biofeedback eletromiográfico. Estudos que analisaram esse método são antigos e apresentam heterogeneidade metodológica, o que dificulta sua reprodução. Dessa forma, é necessário analisar o efeito do método por meio de um ensaio clínico para se obter evidências científicas sobre a intervenção para respaldar a prática clínica baseada em evidências. Objetivo: analisar a efetividade e a duração dos efeitos da terapia vocal associada ao biofeedback eletromiográfico em mulheres com disfonia comportamental. Delineamento do estudo: ensaio clínico, randomizado, controlado e cego. Método: participaram do estudo 22 mulheres (idades entre 18 e 45 anos) com diagnóstico de disfonia comportamental, alocadas de forma randomizada em dois grupos: Grupo Experimental (GE) ­ 11 mulheres que realizaram terapia vocal associada a aplicação do biofeedback eletromiográfico nos músculos esternocleidomastoideo e supra-hioideos; Grupo Placebo (GP) ­ 11 mulheres que realizaram terapia vocal associada a aplicação do biofeedback eletromiográfico placebo. Ambos os grupos realizaram 8 sessões de terapia, duas vezes por semana, com duração de 30 minutos. A terapia vocal de ambos os grupos foi composta por exercícios de trato vocal semiocluído (vibração, humming e fricativo). As avaliações foram realizadas em três momentos: antes, imediatamente após, depois de um e três meses da intervenção fonoaudiológica, e constaram de: avaliação vocal (perceptivo-auditiva e acústica), avaliação eletromiográfica de superfície, autoavaliação vocal, de sintomas vocais e laríngeos, da dor musculoesquelética e da qualidade de vida em voz. Os dados foram analisados estatisticamente, comparando-se os grupos e os momentos de avaliação (p=0,05). Resultados: A terapia vocal proposta promoveu resultados positivos na qualidade vocal, nos sintomas vocais, na qualidade de vida relacionada à voz e na atividade elétrica muscular durante o repouso em mulheres com disfonia comportamental, com ênfase nos aspectos fonatórios e comportamento vocal em nível glótico. Já o biofeedback eletromiográfico promoveu resultados positivos na atividade elétrica muscular durante as tarefas fonatórias e na dor musculoesquelética em mulheres com disfonia comportamental, com base nos aspectos comportamentais e musculares da região extrínseca da laringe, cintura escapular e cervical. Conclusão: Conclui-se que a terapia vocal associada ao biofeedback eletromiográfico tem efetividade equivalente e efeitos que se mantém pelo mesmo tempo na laringe, na voz e na autopercepção de sintomas e da qualidade de vida em voz, e é mais efetiva e tem efeitos que se mantêm por mais tempo na atividade elétrica muscular e na autopercepção da dor musculoesquelética de mulheres com disfonia comportamental do que a terapia vocal realizada de forma tradicional.(AU)

Introduction: dysphonia can affect the respiratory, glottic and ressonantal/articulatory levels, this limits the efficiency of communication and can cause quality of life damages. When the etiology of dysphonia is related to incorrect vocal use, it is classified as behavioral. Although the literature shows the effectiveness of several methods and programs of vocal rehabilitation, few investigate the self-perception and the participation of the body musculature in the dysphonia. In order to improve these issues, the literature proposed the electromyographic biofeedback. The studies that analyzed this method are remote and have methodological heterogeneity which makes it difficult to reproduce. Thus, it is necessary to analyze the effect of the method through a clinical trial to obtain scientific evidence on the intervention to support evidence-based clinical practice. Purpose: to analyze the effectiveness and duration of the effects of vocal therapy associated with electromyographic biofeedback in women with behavioral dysphonia. Study design: randomized controlled blinded clinical trial. Methods: Twenty-two women (18 to 45 years) with a diagnosis of behavioral dysphonia were randomly divided into two groups: Experimental Group (EG) - 11 women participated in vocal therapy associated with the application of electromyographic biofeedback of the sternocleidomastoid and supra-hyoids muscles; Placebo Group (GP) - 11 women participated in vocal therapy associated with the application of placebo electromyographic biofeedback. Both groups performed eight therapy sessions, twice a week, lasting 30 minutes. The vocal therapy of both groups was composed of semioccluded vocal tract exercises (trill, humming and fricative sounds). The evaluations were performed at four time points: before, after, one and three months after the vocal therapy and will consist of the assessments: vocal (auditory-perceptual and acoustic evaluation), surface electromyographic, vocal self-assessment, vocal and laryngeal symptoms, musculoskeletal pain and quality of life in voice. The data were analyzed statistically comparing the groups and the time of evaluation (p0.05). Results: The proposed vocal therapy promoted positive results in vocal quality, laryngeal and vocal symptoms, voice-related quality of life and muscular electrical activity during rest in women with behavioral dysphonia for both groups. Electromyographic biofeedback promoted additional positive results in muscle electrical activity during phonatory tasks and musculoskeletal pain in women with behavioral dysphonia. These results are based on the behavioral and muscular aspects of the extrinsic region of the larynx, scapular and cervical muscles. Conclusion: in this study, the vocal therapy associated with electromyographic biofeedback had equivalent efficacy to traditional therapy in the larynx, voice and self-assessment of symptoms and quality of life. The biofeedback was more effective than traditional therapy on muscular electrical activity and self-perception of musculoskeletal pain and had effects that remained for a longer time in women with behavioral dysphonia.(AU)

Motor evoked potentials in standing and recumbent calves induced by magnetic stimulation at the foramen magnum.

The aims of this study were to determine reference values for magnetic motor evoked potentials (mMEPs) in calves and the influence of position during examination (standing or lateral recumbency). Reference values were determined using 41 healthy Holstein Friesian bull calves aged 1-10 months; standing and lateral recumbency were examined in 11 calves. Maximal magnetic stimulation was performed at the level of the foramen magnum with a magnetic field of 4 T at the coil surface. In standing position, distinct, reproducible mMEPs were obtained in all calves. Onset latency (LAT) (mean ± standard deviation) was significantly shorter in the thoracic limbs (34.4 ± 3.1 ms) than in the pelvic limbs (44.6 ± 3.0 ms). Amplitude (AMPL) was significantly higher in the thoracic limbs (3.7 ± 1.7 mV) than in the pelvic limbs (3.3 ± 1.7 mV) and significantly increased with body length. Age, body weight, height at the withers and rectal temperature had no significant association with LAT or AMPL, and no differences between left and right were noted. In the lateral position, only 64% of the calves showed responses in the four limbs; in these calves, LAT (29.7 ± 4.7 ms) and AMPL (3.0 ± 1.8 mV) in the thoracic limbs were significantly different from AMPL (47.0 ± 7.4 ms) and LAT (2.1 ± 2.1 mV) in the pelvic limbs. In conclusion, mMEPs in limb muscles can be evoked in calves by stimulation at the level of the foramen magnum. mMEPs are more difficult to obtain in lateral recumbency than in standing calves.

Recording Myocentric Relation in a Partially Edentulous Patient: A Case Report.

The masticatory system constitutes four closely interrelated components: Teeth, muscles, nerves, and temporomandibular joints (TMJ). The stable and physiologic rest position of the TMJ is based on the muscle guidance (mainly masticatory, and partially facial), neurally determined and controlled occlusion, integrated together with its peripheral proprioceptors and relax mechanism of the central nervous system. Oral rehabilitation procedures should emphasize on a holistic approach to establish a physiologic relationship of the lower jaw to the base of the cranium resulting in a neuromuscular rest position. This position then would support an occlusion for the stability of the TMJ, the masticatory muscles of the orofacial region and the teeth along with their supporting periodontium. Such a holistic approach becomes more important in cases where the patient not only requires oral rehabilitation but also presents with related TMJ problems. This is a case report where an attempt is made to rehabilitate a patient in a neuromuscular rest position by establishing a myocentric relation.

Periodic limb movements and insomnia, a common but under-recognized association.

Periodic limb movements unlike restless leg syndrome is under diagnosed and unrecognized in medical arena. While robust Western trials have elucidated the association between periodic limb movements and sleep disturbances, it is not well received and recognized in India even in well sophisticated tertiary care hospital. We report a chronic insomnia patient who had sleep disturbances for past 30 years due to periodic limb movements alone. This was diagnosed through polysomnography. This case emphasizes monitoring leg movements during sleep study. This report may open new horizons in improving monitoring in sleep study in clinical setting.

Can triggered electromyography thresholds assure accurate pedicle screw placements? A systematic review and meta-analysis of diagnostic test accuracy.

OBJECTIVE: Triggered electromyography (t-EMG) for pedicle screw placement was introduced to prevent the misplacement of screws; however, its diagnostic value is still debated. This study aimed to clarify the diagnostic value of t-EMG and to compare thresholds. METHODS: We searched MEDLINE, EMBASE, and the Cochrane Library, and 179 studies were identified. Among them, 11 studies were finally enrolled. The pooled sensitivity, specificity, diagnostic odds ratio (DOR), and summary receiver operating characteristics (SROC) plots were analyzed. RESULTS: The enrolled studies included 13,948 lumbar and 2070 thoracic screws. The overall summary sensitivity/specificity/DOR values of t-EMG were 0.55/0.97/42.16 in the lumbar spine and 0.41/0.95/14.52 in the thoracic spine, respectively, indicating a weak diagnostic value. However, subgroup analysis by each threshold value showed that the cutoff value of 8mA in the lumbar spine indicated high sensitivity (0.82), specificity (0.97), and DOR (147.95), thereby showing high diagnostic accuracy of identifying misplaced screws. CONCLUSION: The most useful application of t-EMG may be as a warning tool for lumbar pedicle screw malpositioning in the presence of positive stimulation at a threshold of ⩽8mA. SIGNIFICANCE: t-EMG by screw stimulation may be valuable in the lumbar region at a threshold of ⩽8mA.