Muscle Electrical Activity Research Articles

Fatigue effect on muscle coactivation during inversion movement in females with chronic ankle instability

BACKGROUND: An ankle sprain is a relevant public health issue. Fatigue changes the neuromuscular response in people with chronic ankle instability (CAI). AIM: To evaluate the muscle co-activation on people with chronic ankle instability using cross-correlation analysis. METHOD: Twenty-four healthy women were selected and divided into stability and instability groups. Ankle sprain was simulated with a mechanical platform. Electrical muscle activity (fibularis brevis, FB; fibularis longus, FL; gastrocnemius lateralis, GL; and tibialis anterior, TA) and platform acceleration were recorded at 2KHz. Two sets of 8 right and eight left foot fall in random order were performed before and after the fatigue protocol. Fatigue protocol ended when the volunteer increased the test run time by 150% of the best round. Co-activation was calculated with cross-correlation. Agonist-agonist (FB-FL, FB-GL, and FL-GL) and agonist-antagonist (TA-GL, TA-FB, and TA-FL) pairs were evaluated. Statistical significance was p<0.05. RESULTS: Co-activation was lower for the instability group. Fatigue did not induce changes in 5 out of the 6 analyzed muscle pairs. CONCLUSION: CAI is a factor of joint instability. Fatigue may not be relevant in altering joint stability. Therefore, interventions should be focused on enhancing joint stability.

Does footedness affect bilateral plantar flexor responses to sudden stance perturbations under unilateral lower leg muscular fatigue?

BACKGROUND: Analysis of performance asymmetries has indicated that the right and left cerebral hemispheres are specialized for specific functions of motor control. AIM: In the current investigation, we aimed to evaluate the effect of leg dominance on electrical activation of the plantar flexor muscles in responses to unanticipated stance perturbations in a state muscular fatigue of the dominant leg. METHOD: Fatigue was induced through ankle isometric contraction targeting 40% of maximum voluntary contraction. Muscle activation of the triceps surae of the dominant and non-dominant legs were compared in reactive responses to unanticipated load released from the trunk, leading to forward body sway. Muscular responses were analyzed in two states: pre-fatigue and fatigue of the triceps surae muscles of the dominant leg only. RESULTS: Analysis of magnitude of muscular activation for balance recovery following perturbations revealed fatigue-related compensatory activation in the lateral gastrocnemius muscle, as indicated by over-activation of the non-fatigued/non-dominant leg to compensate for the low muscular activation of the dominant/fatigued leg in the unilateral fatigue state. CONCLUSION: Compensatory behavior between the legs was not evident in the medial gastrocnemius and soleus muscles. Lack of effects related to leg dominance indicates that footedness did not affect automatic muscular responses either in the pre-fatigue or fatigue states.

Comparison of electrical activity of the quadriceps muscle, during implementing some selected soccer kick

Comparison of electrical activity of the quadriceps muscle, during implementing some selected soccer kick

Nerve conduction assessments in patients with lumbar radiculopathy – an observational study

The main aim of this study was to identify the changes in nerve conduction parameters in cases of lumbar radiculopathy due to lumbar spondylosis and intervertebral disc pathology with no clinical neurologic deficit and to identify the potential of nerve conduction studies in the early diagnosis of these cases. Eleven patients aged between 41 and 78 years (mean age 58 ± 13.1 years; 4 males, 36.36%) met the inclusion criteria and agreed to participate in this study. Nerve conduction studies were performed with Neuro‐MEP‐Micro (Figure 1), a digital system designed to record electrical activity of muscles and nerves at 1 or 2‐channel stimulation, and to measure and analyze their parameters. Conduction velocity was reduced in 29.41% of the examined tibial nerves, and in none of the examined peroneal nerves. The registered amplitudes, for none of the tibial or peroneal nerve, have not been lower than the reference values. Patients with reduced tibial conduction velocity had a Grade 2 nerve root involvement on MRI. Nerve conduction studies should be used to complete the physical and imagistic assessment of patients with lumbar radiculopathy, to detect functional abnormalities not only structural ones provided by the MRI.

Electro-localization method using a muscle conductive phantom for needle position detection towards medical training

Simulation in healthcare can help train, improve, and evaluate medical personnel’s skills. In the case of needle insertion/manipulation inside the muscle during an nEMG examination, a training simulator Requires estimating the position of the needle to output the electrical muscle activity in real time according to the training plan. External cameras can be used to estimate the needle location; however, different error sources can make its implementation difficult and new medical sensing technologies are needed. This study introduces and demonstrates the feasibility of a conductive phantom that serves as the medium for needle insertion and senses the 3D needle position based on a technique named electro-localization for the first time. The proposed conductive phantom is designed so that different voltage distributions are generated in the phantom using electrodes placed on its borders. The needle is inserted in the phantom, and the recorded voltages are mapped to spatial coordinates using a finite element method (FEM)-based computational model of the conductive phantom to estimate the 3D needle tip position. Experimental and simulation results of phantom voltage distributions agreed. In 2D mapping (no depth consideration), the needle position error was 1.7 mm, which was marginally reduced if only the central area of the phantom was used (1.5 mm). In 3D mapping, the error was 4 mm. This study showed the feasibility of using a conductive muscle phantom as a new embedded sensor that estimates needle position for medical training of nEMG without relying on external sensors.

Effect of Exercises in Water and Thera-Band on the Electrical Activity of Lower Limb Muscles in People with Pronated Foot During Walking: A Clinical Trial Study

Introduction: The ankle joint is one of the most vulnerable joints in the body due to weight bearing. Pronated foot is one of the most common complications of the lower limbs. Therefore, the aim of the present study was to investigate the effect of exercise protocol in water and theraband on the electrical activity of lower limb muscles in people with pronate foot during walking.
 Methods: The present research was a clinical trial study that was conducted in a semi-experimental and laboratory. The participants of the present study included 45 students of University of Mohaghegh Ardabili, Ardabil, Iran, who had pronated foot. They were selected purposefully and divided into three equal groups. The age range of the subjects was 18-25 years. To measure the electrical activity muscles of lower limbs, it was recorded using an electromyography device. Electromyography data were analyzed using biometric datalite program. In addition, analysis of variance with repeated measurements and bonferroni post hoc test was used, and the significance level was P≤0.05.
 Results: The results showed that there was a significant difference between time*group activity of the gastrocnemius (P=0.001) and semitendinosus (P=0.046) in the three groups of training in water, theraband and control during the heel contact phase. Therefore, using the appropriate post hoc test (LSD), it was shown that the activity of the gastrocnemius muscle in the post-test compared to the pre-test in the group of training in water (P<0.001; d=6.08) and theraband (P<0.001; d=3.66) had a significant increase of 24.03 and 16.46%, respectively. The activity of the semitendinosus muscle in the post-test compared to the pre-test in the water training group (P=0.041; d=4.98) and theraband (P=0.048; d=4.76) had a significant increase of 21.06 and 19.01%, respectively.
 Conclusion: According to the present study, it seems that doing exercises in water and thera-band can play an effective role in improving the range of electrical activity of the muscles on lower limbs of people with pronated foot during walking. In addition, according to the effect size, it was found that training in water had a better effect on the activity of the gastrocnemius and semi tendinosus compared to thera-band.

Venous congestion affects neuromuscular changes in pigs in terms of muscle electrical activity and muscle stiffness.

Early detection of venous congestion (VC)-related diseases such as deep vein thrombosis (DVT) is important to prevent irreversible or serious pathological conditions. However, the current way of diagnosing DVT is only possible after recognizing advanced DVT symptoms such as swelling, pain, and tightness in affected extremities, which may be due to the lack of information on neuromechanical changes following VC. Thus, the goal of this study was to investigate acute neuromechanical changes in muscle electrical activity and muscle stiffness when VC was induced. The eight pigs were selected and the change of muscle stiffness from the acceleration and muscle activity in terms of integral electromyography (IEMG) was investigated in three VC stages. Consequently, we discovered a significant increase in the change in muscle stiffness and IEMG from the baseline to the VC stages (p < 0.05). Our results and approach can enable early detection of pathological conditions associated with VC, which can be a basis for further developing early diagnostic tools for detecting VC-related diseases.

Evolution of surface electromyography: From muscle electrophysiology towards neural recording and interfacing.

Surface electromyography (EMG) comprises a recording of electrical activity from the body surface generated by muscle fibres during muscle contractions. Its characteristics depend on the fibre membrane potentials and the neural activation signal sent from the motor neurons to the muscles. EMG has been classically used as the primary investigation tool in kinesiology studies in a variety of applications. More recently, surface EMG techniques have evolved from single-channel methods to high-density systems with hundreds of electrodes. High-density EMG recordings can be deconvolved to estimate the discharge times of spinal motor neurons innervating the recorded muscles, with algorithms that have been developed and validated in the last two decades. Within limits and with some variability across muscles, these techniques provide a non-invasive method to study relatively large populations of motor neurons in humans. Surface EMG is thus evolving from a peripheral measure of muscle electrical activity towards a neural recording and neural interfacing signal. These advances in technology have had a major impact on our fundamental understanding of the neural control of movement and have exposed new perspectives in neurotechnologies. Here we provide an overview and perspective of modern EMG technology, as derived from past achievements, and its impact in neurophysiology and neural engineering.

Psychophysiological Features of Youth Response to Simulated Situations of Communication

The article analyzes the phenomenon of communication from the position of various scientists. It is noted that any process of communication is accompanied by changes in psychophysiological indicators - the electrical activity of the brain, skin-galvanic reaction, pulse, heart rate, increased breathing. The results of an experimental study aimed at studying the psychophysiological features of young people's responses to simulated situations of communication are presented: direct communication, "live"; mixed format (there is "live communication" and digital communication), as well as communication in a virtual environment. This paper will discuss 3 questionnaire questions out of 34 depending on the emotional inclusion of the subjects. Psychophysiological methods were applied, which allowed to analyze the following indicators: photoplethysmogram, electrical activity of muscles, galvanic skin response, breathing. In conclusion, it is concluded that psychophysiological indicators can be markers of emotional involvement of young people in simulated communication situations.

Effect of Two Types of Thoracolumbosacral Brace (With and Without Sensors) on Electromyography Activity of Selected Muscles in People With Thoracic Kyphosis During Typing

Background and Aims People suffer from neck pain, headache, kyphosis and back pain while working with the computer for a long time, which seems to increase day by day with the advancement of technology. The present study aims to investigate the effect of two types of thoracolumbosacral braces (with and without sensors) on electromyography activity of selected muscles in people with thoracic kyphosis during typing. Methods In this quasi-experimental study, 15 males with thoracic kyphosis volunteered to participate in the study. Subjects performed typing task for one minute at three conditions (with no brace, with a simple brace, and with a brace having sensors). An 8-channel wireless electromyography system was used to record the activity of selected muscles in the upper limb and shoulder area. Repeated measures analysis of variance was used to compare the electrical activity of muscles between different conditions. The significance level was set at 0.05. Results The median frequency of trapezius muscle was significantly lower while using the brace with sensors compared to that without using brace (P=0.005). In median frequency of other muscles, no significant differences were observed among three conditions (P&gt;0.05). Conclusion The use of thoracolumbosacral brace with sensors can reduce the median frequency of trapezius muscle in people with kyphosis. This reduction in median frequency may be related to the passive support of the brace. Reduction of electrical activity in trapezius muscle while using thoracolumbosacral brace can increase the time to reach fatigue.

Effectiveness of Transcutaneous Neuromodulation on Abductor Muscles Electrical Activity in Subjects with Chronic Low Back Pain: A Randomized, Controlled, Crossover Clinical Trial.

Non-specific chronic low back pain (NSCLBP) is a major cause of functional impairment, resulting in consequences like job absenteeism and reduced quality of life. Risk factors such as muscle weakness and tightness have been implicated. Electromagnetic fields have therapeutic effects on human tissue, including pain relief and muscle relaxation. This study aimed to examine the impact of a tape with magnetic particles (MPT) applied to the lumbar area on abductor muscle strength and surface electromyography (sEMG) of the Gluteus Medius and Tensor of the Fascia Lata muscles in individuals with NSCLBP. It was carried out a double-blind, randomized, controlled, crossover trial and with test retest, with 41 consecutive patients younger than 65 years who previously diagnosed with NSCLBP to assess the effect of a MPT over hip abductor muscle strength and activity. sEMG and force data were obtained during the Hip Stability Isometric Test (HipSIT). The HipSIT was used to assess the abduction strength using a hand-held dynamometer and sEMG. The HipSIT uses the maximum voluntary isometric contraction (MVIC). Four trials were recorded and the mean extracted for analysis. The tape was applied with either a MPT or a sham magnetic particle tape (SMPT) bilaterally without tension on from L1 to L5 paravertebral muscles. The significant increase in the recruitment of fibers and the significant increase in the maximum voluntary contraction by applying MPT with respect to the SMPT, correspond to the increases in the Peak Force and the decrease in the time to reach the maximum force (peak time) of both muscles. Application of a MPT in patients with NSCLBP suggests an increase in muscle strength of the Gluteus Medius and Tensor Fascia Lata bilaterally during the HipSIT test. Lumbar metameric neuromodulation with MPT improves muscle activation of the hip musculature.

Bedside Monitor Based on Personal Computer Using STM32F7 Microcontroller

A vital sign examination is one of the important indications used to establish the diagnosis of a disease and is useful for determining the medical treatment plan needed for the patient. An electrocardiograph (ECG) is a parameter in medical equipment used in the process of measuring the electrical activity of the heart muscle by measuring biopotential differences from the body surface. In 2016, cardiovascular disease was the number-one cause of death in the world. This happens because the detection of cardiovascular disease is often late, so a monitoring tool is needed that can monitor the patient's condition quickly and efficiently. The purpose of this research is to create a tool that is used to facilitate the monitoring of patient conditions. The implication of this research is that in the many cases where the signal produced is not perfect and there is still a lot of noise, this can be overcome by using the STM32F7 microcontroller, which has a 16-bit resolution, so that the resulting signal will be better, smoother, and have less noise. produced is very small. The method used in this study was to use a phantom ECG as a comparison and to use five respondents whose BPM values were to be compared with another comparison using a pulse oximeter. The design of this tool uses an ECG analog circuit that is placed on the patient's lead II leads to detect the patient's electrocardiograph signal. Data processing will be done using the STM32F7 microcontroller, and the results of the data processing will be sent to the PC using Visual Basic. The results showed that the BPM error value using a phantom ECG was 2.5%. While the smallest error value is 0,83%. In BPM measurements using 5 respondents, the largest error value was 0.9% and the smallest error value was 0%. The results of these tests indicate that this module can be used to monitor the value of each parameter in accordance with the plan.

A Prochlorperazine-Induced Decrease in Autonomous Muscle Activity during Hindlimb Unloading Is Accompanied by Preserved Slow Myosin mRNA Expression.

Skeletal muscle disuse leads to pathological muscle activity as well as to slow-to-fast fiber-type transformation. Fast-type fibers are more fatigable than slow-type, so this transformation leads to a decline in muscle function. Prochlorperazine injections previously were shown to attenuate autonomous rat soleus muscle electrical activity under unloading conditions. In this study, we found that prochlorperazine blocks slow-to-fast fiber-type transformation in disused skeletal muscles of rats, possibly through affecting calcium and ROS-related signaling.

Fall risk detection mechanism in the elderly, based on electromyographic signals, through the use of artificial intelligence

Introduction: The tests used to classify older adults at risk of falls are questioned in literature. Tools from the field of artificial intelligence are an alternative to classify older adults more precisely. Objective: To identify the risk of falls in the elderly through electromyographic signals of the lower limb, using tools from the field of artificial intelligence. Methods: A descriptive study design was used. The unit of analysis was made up of 32 older adults (16 with and 16 without risk of falls). The electrical activity of the lower limb muscles was recorded during the functional walking gesture. The cycles obtained were divided into training and validation sets, and then from the amplitude variable, select attributes using the Weka software. Finally, the Support Vector Machines (SVM) classifier was implemented. Results: A classifier of two classes (elderly adults with and without risk of falls) based on SVM was built, whose performance was: Kappa index 0.97 (almost perfect agreement strength), sensitivity 97%, specificity 100%. Conclusions: The SVM artificial intelligence technique applied to the analysis of lower limb electromyographic signals during walking can be considered a precision tool of diagnostic, monitoring and follow-up for older adults with and without risk of falls.

Can infant carrier hip belts of 2-inch, 4-inch, and 6-inch dimensions influence trunk muscle activities during front infant carrying tasks?

BackgroundUtilization of infant carriers (ICs) for childcare activities is common and involves varieties of hip belts to offer maximum maternal and infant support. There is a need to establish ergonomic-based guidelines for IC components as a means of improving their supportive roles.ObjectiveThis study evaluated the effects of infant carrier (IC) hip-belt dimensions on the erector spinae (ES) and multifidus (MF) muscles of healthy adult women during front infant carrying tasks.MethodsIt utilized three hip belts with different width dimensions (2 inch, 4 inch, and 6 inch) attached to the IC during three front infant carrying tasks, respectively. During each 5-min trial, the activities of the right and left components of the ES and MF muscles were simultaneously monitored via surface electromyography (EMG). Asymmetry ratios of the normalized EMG values of the right and left components of each muscle were calculated.ResultsUtilization of different hip-belt dimensions did not elicit significant (p < 0.05) differences in the electrical activities of the back muscles as well as in their asymmetry ratios. However, marginal differences in the normalized EMG values showed that the 4-inch belt elicited the highest muscular activities in three of the four studied muscles.ConclusionDuring simulated front infant carrying tasks, hip-belt dimensions of the ICs did not influence back muscle activities in healthy adult women. Long-term effects of IC hip-belt dimensions on back muscle activities should be evaluated in future studies.

The effects of transcutaneous electrical nerve stimulation on muscle activity pattern in professional voice users with muscle tension dysphonia using surface electromyography data: A pilot study

ObjectivesMuscle Tension Dysphonia is a voice disorder, which results in stiffness in the laryngeal extrinsic muscles, intense collision, painful contractions, and vibrations of the vocal cords. Due to the multifactorial identity of Muscle Tension Dysphonia, its therapeutic approach must be multidisciplinary. MethodsThe participants were divided into two groups: a control group (5participants) that received Circumlaryngeal Manual Therapy (CMT) + Placebo Transcutaneous Electrical Nerve Stimulation and an experimental group (5participants) that received Transcutaneous Electrical Nerve Stimulation + CMT. Both groups received 10 sessions of treatment, twice a week, for 40 min each. Before and after treatment, participants were assessed using the Dysphonia Severity Index (DSI) and surface electromyography for their ability to sustain the vowels /e& u/and count from 20 to30. ResultAfter therapy, there were substantial improvements in the DSI (2.72 ± 0.55, P < 0.05) and muscle electrical activity in the control group. The DSI (3.66 ± 0.63, P < 0.05) and muscle electrical activity were also significantly improved in the experimental group after treatment. The findings of the between-group comparison after treatment revealed a significantly greater increase in the Dysphonia Severity Index in the experimental group compared with the control group (P = 0.037). Although there was no significant difference between the two groups in terms of muscle electrical activity, clinically significant changes were more noticeable in the experimental group when compared with the control group. ConclusionsPositive results were seen in both groups. The results demonstrate that both approaches relax vocal tract muscles. As a result, Transcutaneous Electrical Nerve Stimulation was recommended as a complementary treatment for clients with Muscle Tension Dysphonia.

Neuromuscular coupling of obligatory respiratory muscles to inspiratory pressure is reduced in dystrophic (mdx) mice

Neuromuscular coupling (NMC) is a recognised clinical index of inspiratory muscle function which reflects the efficiency of conversion of neural activation to inspiratory pressure. Duchenne muscular dystrophy (DMD) is characterised by respiratory insufficiency culminating in respiratory failure. We investigated inspiratory pressure generating capacity and electrical activation of obligatory inspiratory muscles in X-linked muscular dystrophy ( mdx) mice, to evaluate NMC of diaphragm, external intercostal and parasternal intercostal to inspiratory pressure across a range of behaviours in early established to late progressive disease.In urethane anaesthetised mice (1.7 g/kg i.p.), inspiratory pressure was recorded via a pressure transducer positioned in the thoracic oesophagus. Diaphragm EMG activity was recorded using needle electrodes. Studies were performed in male wildtype (WT) and mdx mice at 4, 8, 12 and 16 months old. Recordings were made at baseline and during sustained tracheal occlusion to task failure, defined as an inability to sustain peak pressure. Peak pressure was determined from the average of five successive peak efforts at the maximum response. The corresponding peak inspiratory EMG activities were determined. Two factor (age x genotype) analysis of variance was performed.Obligatory muscle EMG activities were significantly lower in mdx mice from 4 months of age. Peak inspiratory pressure was significantly greater in mdx at 4 months of age. At 8 months, peak inspiratory pressure was equivalent between WT and mdx followed by a significant decrease in peak inspiratory pressure in 12- and 16-month-old mdx. NMC was lower in mdx mice across the ventilatory and non-ventilatory range, emerging early in dystrophic disease.Reduced NMC of obligatory muscles to inspiratory pressure in mdx mice reveals a greater reliance on accessory muscles to support respiratory performance in dystrophic disease. Remarkably, this burden is adequately accommodated in early disease with a preserved capacity to generate peak inspiratory pressure. We reason that the loss of compensation afforded by accessory muscles to peak inspiratory pressure generation underpins the emergence of respiratory compromise in advanced disease. Our results may have implications for the understanding and treatment of DMD. Funded by Science Foundation Ireland SFI/19/6628 INSPIRE DMD. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

PO-03-097 DEFINING ELECTRODE CONFIGURATION FOR MAPPING MICROANATOMIC REENTRIES SUSTAINING ATRIAL FIBRILLATION

A major challenge in mapping atrial fibrillation (AF) to guide ablation is that it is unclear what resolution is required to map potential regions of interest such as those microanatomic reentries revealed by optical mapping of ex-vivo human hearts (fig. A). The goal of the study was to define the electrode configurations that can identify potential ablation targets as specific EGM traces generated during the conduction through the common path of AF microanatomic reentry. We simulated a microanatomic reentry sustaining AF in anisotropic 3D model of atrial tissue of 40x40x3 mm with an endocardial pectinate muscle of 3x3x15 mm (0.25 mm resolution, fig. B), using Koivumäki-cellular model of human atrial action potential. The simulation also included recordings of endocardial unipolar and bipolar electrodes (3 mm inter-electrode distance, 1 mm length, 2 mm diameter) with different distances and orientations from the pectinate muscle (fig. B). Local activation time map (fig. C) of the simulation showed sub-endocardial microanatomic reentry, with the common path through the pectinate muscle with a cycle length of 110 ms. The electrical activation through the pectinate muscle and atrial wall below the electrodes (Fig. D) was compared to the simulated EGM traces at different distances from the common path (fig. E). On EGMs close to the pectinate muscle (<2mm) electrical activity of reentrant common path can be identified in both unipolar and bipolar EGM signals by peak with amplitude similar or larger than the main atrial wall activation (figs E-F). When bipolar electrodes were perpendicular to the pectinate muscle, the peak amplitude of the common path activity was lower than 25% of the atrial wall peak amplitude. Our simulation suggested that inter-electrode distance to detect sub-endocardial microanatomic reentries sustaining AF should be < 4mm. Mapping was more reproducible for unipolar than for bipolar mapping, as bipolar electrodes were highly sensitive to orientation relative to the common path conduction.

Surface electromyographic characteristics of forearm muscles after ulnar and radius fracture inchildren.

To evaluate the characteristics of forearm muscle activity in children with ulnar and radius fractures during different follow-up periods by surface electromyography. A retrospective analysis was performed on 20 children with ulnar and radius fractures treated with an elastic intramedullary nail from October 2020 to December 2021. All children were treated with transcubital casts after surgery. At 2 months and before taking out the elastic intramedullary nail, surface electromyographic signals were collected on the flexor/extension of the wrist and the maximum arbitrary isometric contraction of the grip strength in the forearm flexor and extensor muscles of the forearm. The root-mean-square values and integrated EMG values of the superficial flexor and extensor digitalis of the healthy side and the affected side were collected at the last follow-up and 2 months after surgery, and the co-systolic ratio was calculated. The root-mean-square values and co-systolic ratio were compared and analyzed, and the Mayo wrist function score was evaluated. The mean follow-up time was (8.4 ± 2.85) months. Mayo scores were (87.42 ± 13.01) and (97.69 ± 4.50) points at the last follow-up and two months after surgery, respectively (p < 0.05). In the test of grip strength, 2 months after surgery, the grip strength of the affected side was lower than that of the healthy side (p < 0.05), and the maximum and mean values of the superficial flexor of the affected side were lower than those of the healthy side (p < 0.05). At the last follow-up, there was no difference in the grip strength between the affected side and the healthy side (p > 0.05), and no difference in the maximum RMS, mean RMS and cooperative contraction ratio of the superficial flexor and digital extensor muscles between the affected side and the healthy side (p > 0.05). Satisfactory results can be obtained after elastic intramedullary napping in children with ulnar and radius fractures. However, 2 months after surgery, the grip strength of the affected side is small, and the electrical activity of the forearm muscle is low during flexion and extension activities of the wrist joint, which has not returned to normal, suggesting that children orthopaedic clinicians should remind children to conduct timely and effective rehabilitation training after the removal of the cast.

Classification of tracheal stenosis with asymmetric misclassification errors from EMG signals using an adaptive cost-sensitive learning method

Upper airway obstruction is characterized by loss of normal airway architecture resulting from various disorders such as infections and asthma. Early detection of airway obstruction is essential to prevent medical deterioration. The objective of this study was to non-invasively identify early-stage tracheal stenosis, using electromyography (EMG) signals of inspiratory muscles. The identification of tracheal stenosis has been defined as an asymmetric misclassification cost problem. Specifically, the EMG signals are used as input to a ResNet-like architecture for tabular data with an Adaptive Cost-Sensitive Learning (AdaCSL) algorithm. The electrical activity of the external intercostal muscle of four healthy individuals was recorded while they breathed through two different tubes, one simulating a narrowed airway and the other simulating a normal airway. Two experiment settings were designed. The first setting aimed to classify tracheal stenosis in a specific subject by training the model on data from other subjects, reflecting the case of diagnosing a new subject. To overcome multi-subject variations, the second setting aimed to classify tracheal stenosis by mixing all subjects’ training and test data. The ResNet-like architecture with an AdaCSL algorithm was significantly better in the first experiment setting with costs that were 43%, 48%, and 59% lower than the cost of the second-best alternative for three different misclassification cost values. It also achieved a lower cost in the second experiment setting over other classifiers. The experiments emphasize the capability of using inspiratory muscle EMG signals to diagnose respiratory disease and demonstrate the usefulness of the AdaCSL algorithm for personalized monitoring.