Muscle Activity In Patients Research Articles

Electrical activity of expiratory muscles in type 2 diabetes mellitus

Aim. To study the functional state of the expiratory muscles in patients with type 2 diabetes mellitus on the basis of changes in their electrical activity when using a functional test with a static expiratory effort. Materials and methods. 47 patients with type 2 diabetes mellitus and 40 patients without disorders of carbohydrate metabolism were examined. To study the electrical activity of the expiratory muscles, surface electromyography (EMG) of the external oblique abdominal muscle (OAM), rectus abdominis muscle (RAM), and internal intercostal muscles (IIM) was performed using a functional test with a static expiratory effort. Results. When performing a functional test with a static expiratory effort in both groups, a decrease in the frequency and an increase in the amplitude of EMG was observed, however, in patients with type 2 diabetes mellitus, these changes were less pronounced. There were also differences in the dynamics of changes in EMG indicators. In patients with type 2 diabetes mellitus, the decrease in the frequency of EMG OAM began from 10 seconds of the test, IIM – from 15 seconds, in the comparison group – from 5 and 10 seconds, respectively. The OAM EMG amplitude in the main group did not change significantly, in the comparison group it increased from 5 seconds of expiratory effort. At the 10th second of the test, the amplitude index of the EMG OAM in patients with type 2 diabetes mellitus was 10.4% lower (p=0.027) than in the comparison group, and at the 15th second – by 10.5% (p=0.033). Conclusion: The change in the electrical activity of the expiratory muscles in patients with type 2 diabetes mellitus is due to the slowed down dynamics of the frequency-amplitude characteristics of the EMG OAM, uncompensated IIM fatigue, as well as lower values of the OAM EMG amplitude when performing a functional exercise test with a static expiratory effort.

Masseter Muscle Activity in Orthodontically Treated Patients with a History of Temporomandibular Joint Disorder: An Electromyographic Study

The present study aimed to evaluate the surface electromyography (sEMG) activity of the masseter muscles in patients with a history of temporomandibular joint disorder (TMJD) who received orthodontic treatment. In total, 22 participants aged 18–35 years old were included in this study. They were divided into the control group (patients without a history of TMJD [n = 11]) and the test group (those with a history of TMJD [n = 11]). Each participant underwent sEMG of the right and left masseter muscles at 5-s maximum voluntary contraction (MVC). Results showed that the TMJD group had a lower sEMG activity of masseter muscles at MVC than the non-TMJD group. However, the differences were not statistically significant (p > 0.05, t-test). The Spearman’s correlation coefficient test revealed a weak negative correlation between muscle activity on sEMG and history of TMJD (p > 0.05). In conclusion, orthodontically treated patients in TMJD group have reduced masseter muscle activity during MVC, compare to the non-TMJD group.

Assessment of the bioelectric activity of the masticatory muscles in orthopedic treatment with partial removable plate prostheses

Relevance. According to a number of authors, it is known that full adaptation to complete removable dentures occurs within 3 months [3–5, 9]. The main criterion for patients getting used to removable dentures is the synchronization of the work of the masticatory muscles and, as a consequence, the normalization of the chewing function. The aim of the study was to evaluate the bioelectrical activity of the masticatory muscles in patients using the CSPP.Materials and methods. In patients of the control (n = 23) and main (n = 63) groups, electromyographic examination was performed using the electroneuromyographic system "Synapsis" (Neurotechnology, Russia). Registration of the bioelectric activity of the chewing muscles was carried out directly on the day of applying the prostheses, after 1 and 3 months, respectively.Results and discussion. The electromyographic indices of the masticatory muscles in the patients of the control group decreased within one month after the treatment and amounted to 231 ± 18.2 μV for the right and 229 ± 16.1 μV for the left proper chewing muscles. The values were also reduced for the right and left temporal muscles – 228 ± 15.2 μV and 225 ± 24.1 μV (p < 0.05). It should be noted that the electromyographic parameters in patients of the main group were comparable to the lower limit of the norm and amounted to 269 ± 16.5 μV and 256 ± 20.4 μV, respectively, after one month of treatment.Conclusions. In the treatment of dysfunction of the temporomandibular joint with the use of thermoplastic prostheses, an increase in the biopotentials of the masticatory muscles is observed. In the orthopedic treatment of patients with terminal dentition defects using thermoplastic prostheses, the electromyographic parameters of the masticatory muscles are most close to normal after 3 months of using these prostheses.

Muscle Activity Before and After Subacromial Injection.

Shoulder muscle activation in patients with subacromial impingement is highly cited and variable in the literature. Differences between studies could be due to artifacts introduced by normalization practices in the presence of pain. Ultimately, this lack of knowledge pertaining to pathogenesis limits the clinical treatment and restoration of muscular function. A total of 21 patients with stage 2 subacromial impingement and 21 matched controls were recruited for EMG testing of their affected shoulder during an arm elevation task. The patients were tested before and after receiving an injection to their subacromial bursa. The EMG from 7 shoulder muscles were measured before and after treatment during humeral motion in the scapular plane. Our findings indicate an increase in anterior deltoid, middle deltoid, and upper trapezius activity following the injection; further, this trend extended to the controls. The control subjects had a greater activation of the latissimus dorsi at peak arm elevation when compared with the patient group postinjection. Our results indicate that a reduction in subacromial pain is associated with changes in shoulder muscle recruitment, primarily of the deltoid. This change in deltoid activity may lend evidence to rotator cuff function in patients without rotator cuff tears.

Physiological Effects of Voice Therapy for Aged Vocal Fold Atrophy Revealed by EMG Study

ObjectivesAge-related voice changes are characterized as breathy, weak and strained, and a deterioration in vocal function in the elderly has been putatively linked to a reduced intensity of speech. They contribute to undesirable voice changes known as presbyphonia. These changes are caused by histological alterations in the lamina propria of the vocal fold mucosa and atrophy of the thyroarytenoid muscle, as well as by decreased respiratory support. There are several clinical studies on presbylarynx dysphonia showing the effectiveness of voice therapy. However, physiological changes of the presbylarynx following voice therapy have not been verified. The purpose of this prospective study was to demonstrate the clinical effectiveness of voice therapy for rehabilitating presbylarynx dysphonia, using vocal function assessments and thyroarytenoid muscular activity detection on laryngeal electromyography (LEMG). Methods10 patients who were diagnosed with aged vocal fold atrophy from ages 60 to 87 years (mean age: 72 years) underwent approximately 12 weeks of voice therapy, mainly using forward-focused voice and vocal resistance training. Stroboscopic examination, aerodynamic assessment, acoustic analysis, Voice Handicap Index (VHI)-10, and LEMG were performed pre– and post–voice therapy. Vocal fold vibratory amplitude (VFVA) was measured by image analysis from the stroboscopic examinations. Turns analysis during steady phonation on LEMG was also assessed. ResultsMaximum phonation time, subglottic pressure, jitter, shimmer, VFVA, and VHI-10 significantly improved after voice therapy. The number of turns per second on LEMG also significantly increased. ConclusionOur data suggest that voice therapy may improve vocal function and thyroarytenoid muscle activity in patients with aged vocal fold atrophy.

Электромиографическое исследование биоэлектрической активности мышц нижних конечностей у пациентов с дегенеративным стенозом, осложненным синдромом нейрогенной перемежающейся хромоты

Статья посвящена исследованию и оценке функционального состояния нервно-мышечного аппарата методом интерференционной электромиографии пациентов с дегенеративным стенозом поясничного отдела позвоночника, осложненного нейрогенной перемежающейся хромотой. Полученные данные свидетельствуют о наличии неблагоприятных признаков в организации биоэлектрической активности мышц у больных со стенозами на уровне поясничного отдела позвоночника как в состоянии покоя, так и после специфической нагрузки. Снижение биоэлектрической активности мышц после нагрузочного теста связано с замедлением, а также частичной или полной блокадой проведения возбуждения в разных структурных элементах двигательных единиц, что подтверждают данные настоящего исследования.

Myofunctional parameters in patients using full removable dentures with progenic and prognathic ratio of the anterior segments of the edentulous jaws

The aim study was to construct artificial dentitions based on the method of mathematical modeling with the progenic and prognatic ratios of toothless frontal segments and to analyze the functional activity of the masticatory muscles in patients using dentures made in this way, compared with standard prosthetic structures. To compare and interpret the data obtained, electromyographic studies were performed in the control group (16 people), whose teeth were made using the traditional method, and the main group (22 people), whose artificial teeth were formed according to individual mathematical calculations, taking into account the size of the sagittal gap of the frontal segments of the progenic and prognatic ratio of toothless jaws. Statistical processing of the results of the electro-myographic study was carried out using the Statistica application software package. The digital data were processed by the method of variational statistics using the Student's t-test. The analysis of the obtained data showed the advantages of using individual mathematical calculations when solving the issue of tactics for constructing dentitions in the frontal segment of toothless jaws, taking into account the degree of the sagittal gap in the progenic and prognatic correlation of the jaws and their possible combinations.

Responses in knee joint muscle activation patterns to different perturbations during gait in healthy subjects

PurposeTo compare the responses in knee joint muscle activation patterns to different perturbations during gait in healthy subjects. ScopeNine healthy participants were subjected to perturbed walking on a split-belt treadmill. Four perturbation types were applied, each at five intensities. The activations of seven muscles surrounding the knee were measured using surface EMG. The responses in muscle activation were expressed by calculating mean, peak, co-contraction (CCI) and perturbation responses (PR) values. PR captures the responses relative to unperturbed gait. Statistical parametric mapping analysis was used to compare the muscle activation patterns between conditions. ResultsPerturbations evoked only small responses in muscle activation, though higher perturbation intensities yielded a higher mean activation in five muscles, as well as higher PR. Different types of perturbation led to different responses in the rectus femoris, medial gastrocnemius and lateral gastrocnemius. The participants had lower CCI just before perturbation compared to the same phase of unperturbed gait. ConclusionsHealthy participants respond to different perturbations during gait with small adaptations in their knee joint muscle activation patterns. This study provides insights in how the muscles are activated to stabilize the knee when challenged. Furthermore it could guide future studies in determining aberrant muscle activation in patients with knee disorders.

The Effect of Calf Muscle Power Strengthening and Step on the Length, Symmetry, and Obstacle-Overcoming Capacity and Muscle Activity in Stroke Patients

Purpose: This study is to see if the calf muscle movement affects the length of stride, symmetry, and ability to overcome obstacles, and muscle activity in patients with hemiplegia. Methods: Electromagnetic signals were first measured by ankle plantar flexion or muscle testing in a supine position with 12 patient ankle plantar flexor in the standing position. In the second measurement, the length and symmetry of stride are measured through the gait analyzer. In the third measurement, the ability to measure obstacles was measured. The paired- T test revealed a significant difference. Results: After the intervention, the step length was significantly decreased (p .05), between pre- and post-intervention. Conclusion: The results of this study show that the length of stride, ability to overcome obstacles, muscular activity, and muscle strength are increased more after exercise. Therefore, it is a movement that requires patients with hemiplegia to aim for calf muscle exercise because it increases the length of step in their daily lives, overcomes obstacles, and has a positive effect on muscle activity and muscle strength.

The Relationship between Dynamic Knee Valgus and Lower Extremity Muscle Activity in Patients with Chronic Ankle Instability

The Relationship between Dynamic Knee Valgus and Lower Extremity Muscle Activity in Patients with Chronic Ankle Instability

Comparing myofascial meridian activation during single leg vertical drop jump in patients with anterior cruciate ligament reconstruction and healthy participants.

Muscles work synergistically to support the body during landing. Myofascial meridians have been described to classify muscles into functional synergies. The role that these functional lines plays in positioning the trunk and lower extremity of patients with anterior cruciate ligament reconstruction (ACLR) and healthy athletes during drop landing tasks remains unclear. The purpose of this study was to compare the front and back functional lines (FFL and BFL) muscle activation in patients with ACLR and healthy participants during single leg vertical drop jump (SLVDJ). Thirty-two male athletes (post-ACLR = 16, healthy = 16) participated (age = 23.3 ± 2.3 years). Superficial electromyography of FFL (adductor longus [AL], rectus abdominis [RA], pectoralis major) and BFL (vastus lateralis [VL], gluteus maximus [GMax], latissimus dorsi [LD]) was collected during the SLVDJ and compared at initial contact and maximum knee flexion between groups using t-tests and limbs using paired-samples t-tests. In the FFL, the AL (p < 0.05) and RA (p < 0.05) muscles were more active in the healthy group compared to the ACLR group at initial contact and maximum knee flexion. PM demonstrated greater activation in the healthy group only at maximum knee flexion (p < 0.05). In the BFL, the VL (p < 0.05) and GMax (p < 0.05) muscles were more active in the ACLR group, whereas the LD (p < 0.05) muscles demonstrated greater activation in the healthy group at initial contact and maximum knee flexion. There were no healthy group inter-limb differences in FFL and BFL activation. ACLR participants demonstrated greater non-injured limb VL, AL, GMax and LD activation (p < 0.05) and greater injured limb PM and RA activation (p < 0.05). Based on the present data, patients after ACLR may present with an alteration in BFL and FFL muscles activation during a drop jump task. Functional line muscles during dynamic activities may change lower extremity positioning and lead to increase ACL injury risk.

Temporal Changes in Electromyographic Activity and Gait Ability during Extended Walking in Individuals Post-Stroke: A Pilot Study.

Abnormal gait, particularly in patients with stroke, causes neuromuscular fatigue. We aimed to clarify temporal changes in gait performance and lower limb muscle activity during extended walking in people with stroke hemiplegia. Twelve adults with stroke and eleven healthy controls performed an extended trial involving 20-min continuous walk at a comfortable speed. The primary outcome was electromyography amplitude during the trial and secondary outcomes were walking performance and the instantaneous mean frequency of electromyography during the trial. Data at 1, 6, 12, and 18 min after initiating walking were compared. Performance during extended walking in people with stroke was maintained over time. The electromyography amplitude decreased in the tibialis anterior during the pre-swing phase and increased in the rectus femoris during the single-support phase over time; these changes were similar on the paretic and nonparetic sides. Instantaneous mean frequency decreased over time on the nonparetic side in the tibialis anterior and on the paretic side in the rectus femoris. Healthy subjects did not show any changes over time. The changes in muscle activity in patients with stroke differed between the paretic and nonparetic sides, muscle type, and gait phase; walking performance was maintained despite being affected by neuromuscular fatigue.

Multi-axis destabilisation device influences plantar pressure distribution in adults with chronic ankle instability

ABSTRACT Patients with chronic ankle instability (CAI) walk with increased lateral plantar pressure, precipitating future injuries. Gait retraining to medially shift plantar pressure may prevent recurrent injury. We assessed if a multi-axis destabilisation device changed plantar pressure and muscle activity in patients with CAI during walking. Twelve adults with CAI (age: 23.6 ± 5.0 years; body mass index: 26.7 ± 4.5 kg/m2) participated. Insole plantar pressure and electro-myography were collected synchronously during treadmill walking. The destabilisation device had a half-sphere under both the rearfoot and forefoot. Two 30s walking trials were recorded at baseline, first without and second with the destabilisation device. After 20 min of walking with the destabilisation device, two 30s post-walking trials were collected, first with and second without the destabilisation device. The middle 10 steps of each trial were extracted, plantar pressure quantified, and data averaged across steps for repeated measures ANOVA analysis. Electromyographic data wereextracted from 50 ms pre- through 200 ms post-initial contact. The centre of pressure shifted medially during destabilisation device use (P < 0.002) versus baseline. This shift was notretained upon device removal. Thus, the device capably shifts plantar pressure while worn. Its effects beyond a single sessionare unknown.

An Endurance-Dominated Exercise Program Improves Maximum Oxygen Consumption, Ground Reaction Forces, and Muscle Activities in Patients With Moderate Diabetic Neuropathy.

BackgroundThe prevalence of diabetes worldwide is predicted to increase from 2.8% in 2000 to 4.4% in 2030. Diabetic neuropathy (DN) is associated with damage to nerve glial cells, their axons, and endothelial cells leading to impaired function and mobility.ObjectiveWe aimed to examine the effects of an endurance-dominated exercise program on maximum oxygen consumption (VO2max), ground reaction forces, and muscle activities during walking in patients with moderate DN.MethodsSixty male and female individuals aged 45–65 years with DN were randomly assigned to an intervention (IG, n = 30) or a waiting control (CON, n = 30) group. The research protocol of this study was registered with the Local Clinical Trial Organization (IRCT20200201046326N1). IG conducted an endurance-dominated exercise program including exercises on a bike ergometer and gait therapy. The progressive intervention program lasted 12 weeks with three sessions per week, each 40–55 min. CON received the same treatment as IG after the post-tests. Pre- and post-training, VO2max was tested during a graded exercise test using spiroergometry. In addition, ground reaction forces and lower limbs muscle activities were recorded while walking at a constant speed of ∼1 m/s.ResultsNo statistically significant baseline between group differences was observed for all analyzed variables. Significant group-by-time interactions were found for VO2max (p < 0.001; d = 1.22). The post-hoc test revealed a significant increase in IG (p < 0.001; d = 1.88) but not CON. Significant group-by-time interactions were observed for peak lateral and vertical ground reaction forces during heel contact and peak vertical ground reaction force during push-off (p = 0.001–0.037; d = 0.56–1.53). For IG, post-hoc analyses showed decreases in peak lateral (p < 0.001; d = 1.33) and vertical (p = 0.004; d = 0.55) ground reaction forces during heel contact and increases in peak vertical ground reaction force during push-off (p < 0.001; d = 0.92). In terms of muscle activity, significant group-by-time interactions were found for vastus lateralis and gluteus medius during the loading phase and for vastus medialis during the mid-stance phase, and gastrocnemius medialis during the push-off phase (p = 0.001–0.044; d = 0.54–0.81). Post-hoc tests indicated significant intervention-related increases in vastus lateralis (p = 0.001; d = 1.08) and gluteus medius (p = 0.008; d = 0.67) during the loading phase and vastus medialis activity during mid-stance (p = 0.001; d = 0.86). In addition, post-hoc tests showed decreases in gastrocnemius medialis during the push-off phase in IG only (p < 0.001; d = 1.28).ConclusionsThis study demonstrated that an endurance-dominated exercise program has the potential to improve VO2max and diabetes-related abnormal gait in patients with DN. The observed decreases in peak vertical ground reaction force during the heel contact of walking could be due to increased vastus lateralis and gluteus medius activities during the loading phase. Accordingly, we recommend to implement endurance-dominated exercise programs in type 2 diabetic patients because it is feasible, safe and effective by improving aerobic capacity and gait characteristics.

The effect of Horse riding exercise, McKenzie Exercise on back pain and muscle activity in patients with low back pain

The effect of Horse riding exercise, McKenzie Exercise on back pain and muscle activity in patients with low back pain

The comparison of the shoulder muscle activation in patients with rotator cuff tear under an abduction brace among the three postures

Background: Immobilization using an abduction brace is essential for the relaxation of the rotator cuff and scapular muscles and the prevention of a retear in patients with rotator cuff tear after arthroscopic rotator cuff repair (ARCR). However, thus far, the comparison of the scapular muscle activities has not been compared among different postures under an abduction brace in patients after ARCR. Objectives: The purpose of our study was to compare the scapular muscle activities among the supine position, sitting position, and walking under an abduction brace before and after ARCR Study Design: Observational, repeated measures study. Methods: Twelve patients with full-thickness rotator cuff tears were studied. The mean patient age was 64.7 years. The scapular muscle activations of the ipsilateral limbs were measured using surface electromyography in three postures: supine position, sitting position, and walking. The integrated electromyography relative values of the upper trapezius, anterior deltoid, middle deltoid, and biceps brachii were compared preoperatively and at two weeks after ARCR. Results: The trapezius, biceps brachii, and middle deltoid in the walking showed significantly higher integrated electromyography relative values than those in the supine position, preoperatively and at two weeks after surgery. The anterior deltoid in the sitting position had significantly higher integrated electromyography relative values than those in the supine position. Conclusions: Postures affected the scapular muscle activities in ARCR patients under an abduction brace. Understanding the influence of posture on the scapular muscle activity after ARCR will help rehabilitation accurately and appropriately.

Investigation of inspiratory intercostal muscle activity in patients with spinal cord injury: a pilot study using electromyography, ultrasonography, and respiratory inductance plethysmography.

[Purpose] The respiratory function in patients with cervical spinal cord injury is influenced by inspiratory intercostal muscle function. However, inspiratory intercostal muscle activity has not been conclusively evaluated. We evaluated the inspiratory intercostal muscle activity in patients with cervical spinal cord injury by using inspiratory intercostal electromyography, respiratory inductance plethysmography, and ultrasonography. [Participants and Methods] Three patients with cervical spinal cord injury were assessed. The change in mean amplitude (rest vs. maximum inspiration) was calculated by using intercostal muscle electromyography. Changes in intercostal muscle thickness (resting expiration and maximum inspiration) were also evaluated on ultrasonography. The waveform was converted to spirometry ventilation with respiratory inductance plethysmography, and the waveform at the xiphoid was considered to determine the rib cage volume. Each index was compared with the inspiratory capacities in each case. [Results] Intercostal muscle electromyography failed to measure the notable myoelectric potential in all the patients. The rib cage volume was higher at higher inspiratory capacities. The changes in muscle thickness were not significantly different between the patients. [Conclusion] The rib cage volume (measured with inductance plethysmography) was greater in the patients with cervical spinal cord injury when inspiratory intercostal muscle activity was high. Respiratory inductance plethysmography can capture inspiratory intercostal muscle function in patients with cervical spinal cord injury.

Changes in muscle activity in patients with primary chronic headache

Changes in muscle activity in patients with primary chronic headache

Changes in muscle activity in patients with primary chronic headache

Changes in muscle activity in patients with primary chronic headache

The Effects of Squat Exercises with Vertical Whole-Body Vibration on the Center of Pressure and Trunk Muscle Activity in Patients with Low Back Pain

The Effects of Squat Exercises with Vertical Whole-Body Vibration on the Center of Pressure and Trunk Muscle Activity in Patients with Low Back Pain