How Does Stroke Affect Skeletal Muscle? State of the Art and Rehabilitation Perspective

Focal muscle vibration and action observation: a combined approach for muscle strengthening

Muscle strength is essential for autonomy in daily activities and performance in sports activities. Yet, conventional strength training is challenging during recovery from pathological conditions. This study investigates a novel combined intervention employing Focal Muscle Vibration (FMV) and Action Observation (AO) to enhance muscle strength. Twenty-seven healthy volunteers (18 females and 9 males, aged 22 to 42 years) were enrolled for an intervention-control study comparing 2 groups: the intervention group received AO treatment with FMV on the right leg, and the control group underwent only FMV on the right leg.  This design allowed the comparison of four conditions: FMV+AO (intervention group, right leg), AO alone (intervention group, left leg), FMV alone (control group, right leg), and no-treatment NT (control group, left leg). The treatment, conducted five times a week (Mon-Fri) for two weeks, involved a 20-minute session of FMV on the right quadriceps,  coupled, for the intervention group, with the observation of a gym training video. The assessments of Maximum Voluntary Contraction (MVC), and fatigue coefficient (FC) expressed at knee extension bilaterally were measured at the beginning (T0), after the first week (T1), at the end of treatment (T2), and one-week post-intervention for the follow-up (T3). The FMV+AO group demonstrated a significant improvement in MVC over time, reaching statistical significance at T2 and maintaining the gain at T3. In contrast, all the other conditions demonstrated milder MVC increases without statistical significance. FC did not differ significantly in any condition. The combination of FMV and AO optimized muscle strengthening, offering insights for targeted treatments in various settings.

Characteristic brain functional activation and connectivity during actual and imaginary right-handed grasp

We used 34-channel functional near infrared spectroscopy to investigate and compare changes in oxyhemoglobin concentration of brain networks in bilateral prefrontal cortex, sensorimotor cortex, and occipital lobe of 22 right-handed healthy adults during executive right-handed grasp (motor execution task) and imagined right-handed grasp (motor imagery task). Then calculated lateral index and functional contribution degree, and measured functional connectivity strength between the regions of interest. In the motor executive block task, there was a significant increase in oxyhemoglobin concentration in regions of interest except for right occipital lobe (P<0.05), while in the motor imagery task, all left regions of interest's oxyhemoglobin concentration increased significantly (P<0.05). Except the prefrontal cortex in motor executive task, the left side of the brain was dominant. Left sensorimotor cortex played a major role in these two tasks, followed by right sensorimotor cortex. Among all functional contribution degree, left sensorimotor cortex, right sensorimotor cortex and left occipital lobe ranked top three during these tasks. In continuous acquisition tasks, functional connectivity on during motor imagery task was stronger than that during motor executive task. Brain functions during two tasks of right-hand grasping movement were partially consistent. However, the excitability of brain during motor imagery was lower, and it was more dependent on the participation of left prefrontal cortex, and its synchronous activity of the whole brain was stronger. The trend of functional contribution degree was basically consistent with oxyhemoglobin concentration and lateral index, and can be used as a novel index to evaluate brain function. [ChiCTR2200063792 (2022-09-16)].

The effect of fascial manipulation therapy on lower limb spasticity and ankle clonus in stroke patients

Lower limb spasticity and clonus are common sequelae after cerebral stroke. An important part of their etiopathogenesis has been related to the peripheral component of spasticity. Rheological properties of the tissues seem to be involved. Several studies highlighted anatomical and functional changes in the connective structures. The fasciae might be implicated in the pathological process. Thus, this study intends to investigate the effect of the Fascial Manipulation (FM) technique on triceps surae in stroke patients through a clinical randomized controlled trial, to provide a reference for clinical treatment of lower limb spasticity and ankle clonus. A total of 40 patients with post-stroke ankle clonus were selected and divided into a control group and an observation group by random number table method, with 20 cases in each group. Both groups received conventional rehabilitation therapy, while the FM group received Fascial Manipulation based on conventional rehabilitation therapy. Before the first treatment and after 3 weeks of treatment, the Comprehensive Spasticity Scale (CSS), the Passive Range Of Motion (PROM), the simplified Fugl-Meyer motor function score (FMA), and the Modified Ashworth Scale (MAS) were used to assess the degree of ankle clonus, ankle passive range of motion, and lower limb motor function of the two groups of patients. Before treatment, there was no statistically significant difference between the control group and the FM group in terms of CSS, PROM, FMA, and MAS of the affected lower limbs (P>0.05). After 3 weeks of treatment, the CSS and MAS of the affected lower limbs in the control group and FM group decreased, while PROM and FMA increased compared to pre-treatment evaluation, with statistically significant differences (P<0.05). Moreover, the FM group showed a statistically significant decrease in CSS and MAS, as well as an increase in PROM and FMA, compared to the control group (P<0.05). Conclusions: Fascial manipulation in addition to conventional therapy can effectively reduce spasticity and ankle clonus in stroke patients in a short time, and improve the passive range of motion of the ankle joint and the function of lower limbs.

Immediate effects of TECAR therapy on lower limb to decrease hypertonia in chronic stroke survivors: a randomized controlled trial

PURPOSE

To analyze immediate effects of TECAR therapy (TT) to reduce lower limb hypertonia and improve functionality in chronic post-stroke.

MATERIALS AND METHODS

It is a single-blind randomized controlled clinical trial. A total of 36 chronic stroke survivors were divided into two groups. The experimental group received a single 30-minute session of TT with functional massage (FM) on lower limb. The control group received a single 30-minute session sham treatment of TT plus FM. The primary outcome measure was hypertonia (Modified Ashworth Scale, MAS). Secondary outcomes were gait speed (4-Meter Walk-Test), standing knee-flexion (Fugl-Meyer Assessment Scale IV-item), change in weight bearing ankle dorsiflexion (Ankle Lunge Test, ALT), and functional lower limb strength (5-Times Sit-to-Stand Test). All measurements were performed at baseline, immediately and 30-minutes after treatment.

RESULTS

There was a group-time interaction in MAS-knee (p = 0.044), MAS-ankle (p = 0.018) and ALT (p = 0.016) between T1 and T0 (p<.0001) and T2 and T0 (p<.0001) for the experimental group. There was a significant increase in ALT between T1 and T0 (p = 0.003) in the control group.

CONCLUSIONS

A single session of TT performed at the same time as FM immediately reduces plantar-flexors and knee-extensor muscle hypertonia and increases change in weight bearing ankle dorsiflexion in chronic stroke survivors.

The impact of palliative care on the frailty-stroke continuum: from theoretical concepts to practical aspects

With a constant increase in prevalence and incidence worldwide, stroke remains a public health issue in the 21st century. Additionally, population aging inevitably leads to increased vulnerability in the general population, a clinical state known as frailty. While there are adequate guidelines on the treatment of stroke in the acute setting, there are a lot of gaps regarding the chronic management of stroke patients, particularly the frail ones. From the therapeutic point of view, palliative care could be the key to offering complex and individualized treatment to these frail chronic stroke patients. In the context of the heterogeneous data and incomplete therapeutic guidelines, this article provides a new and original perspective on the topic, aiming to increase awareness and understanding and improve palliative care management in stroke patients. Based on current knowledge, the authors describe a new concept called the frailty-stroke continuum and offer a detailed explanation of the intricate stroke-frailty connection in the first part. After understanding the role of palliative care in managing this kind of patients, the authors discuss the most relevant practical aspects aiming to offer an individualized framework for daily clinical practice. The novel approach consists of developing a four-step scale for characterizing frail stroke patients, with the final aim of providing personalized treatment and correctly evaluating prognosis. By pointing out the limitations of current guidelines and the challenges of new research directions, this article opens the pathway for the better evaluation of frail stroke patients, offering a better perception of patients' prognosis.

Immediate effects of trunk Kinesio Taping® on functional parameters in the acute stage of patients with mild stroke: A randomized controlled trial

BACKGROUND

Improving early trunk control, balance, and sitting activity following acute stroke is critical for functional prognosis.

PURPOSE

To compare the immediate efficacy of Kinesio Taping® (KT) application on anterior and posterior trunk muscles in terms of improving trunk control, balance, and sit-to-stand performance in the acute stage of stroke.

METHODS

Sixty-nine patients with acute mild stroke were allocated to the anterior KT group (AKT) (age = 65.95 ± 9.67; 12 females, 11 males; Modified Rankin Score = 3), posterior KT group (PKT) (age = 65.39 ± 10.39; 10 females, 13 males; Modified Rankin Score = 3), and control group (CG) (age = 65.34 ± 8.91; 11 females, 12 males; Modified Rankin Score = 2). Trunk control, balance, and sit-to-stand performance were assessed at the baseline and after 45 minutes and 48 hours post-KT. Data were analyzed using repeated-measures ANOVA.

RESULTS

All outcome measures scores improved in all groups significantly after 48 hours (p < .001). A significant improvement after 45 minutes was only seen in trunk control compared to the CG (p < .001; d = 1.32 for AKT and p = .038; d = 0.75 for PKT). Trunk control, balance, and sit-to-stand performance improved in both AKT and PKT compared to the CG at 48 hours post-taping. Trunk control (p < .001; d = 0.26) and balance (p < .001; d = 0.72) results were in favor of the AKT, while sit-to-stand performance results did not make a difference between KT groups (p = .335; d = 0.47).

CONCLUSION

KT application on anterior or posterior trunk muscles was effective for improving trunk control, balance, and sit-to-stand performance in acute stage of stroke in the short term. KT application on anterior trunk muscles had the advantage of improving trunk control and balance.

Effects of home-based neurostimulation on outcomes after stroke: a systematic review and meta-analysis

BACKGROUND

Home-based rehabilitation is a cost-effective means of making services available for patients. The aim of this study is to determine the evidence in the literature on the effects of home-based neurostimulation in patients with stroke.

METHOD

We searched PubMED, Embase, Web of Science, Scopus, and CENTRAL for randomized controlled trials on the subject matter using keywords such as stroke, electrical stimulation and transcranial direct current stimulation. Information on participants' characteristics and mean scores on the outcomes of interest were extracted. Risks of bias and methodological quality of the included studies were assessed using Cochrane Risks of bias tool and PEDro scale respectively. The data was analyzed using both narrative and quantitative syntheses. In the quantitative synthesis, meta-analysis was carried out using random effect model analysis.

RESULT

The results showed that, home-based neurostimulation is superior to the control at improving upper limb muscle strength (SMD = 0.72, 95% CI = 0.08 to 1.32, p = 0.03), functional mobility (SMD = -0.39, 95% CI = -0.65 to 0.14, p = 0.003) and walking endurance (SMD = 0.33, 95% CI = 0.08 to 0.59, p = 0.01) post intervention; and upper limb motor function (SMD = 0.9, 95% CI = 0.10 to 1.70, p = 0.03), functional mobility (SMD = -0.30, 95% CI = -0.56 to -0.05, p = 0.02) and walking endurance (SMD = 0.33, 95% CI = 0.08 to 0.59, p = 0.01) at follow-up.

CONCLUSIONS

Home-based neurostimulation can be used to improve upper and lower limb function after stroke.

Reliability of ankle dorsiflexor muscle strength, rate of force development, and tibialis anterior electromyography after stroke

Background

Measures of hemiparetic ankle dorsiflexor muscle strength and rate of force development (RFD) are often used to determine the efficacy of rehabilitation interventions after stroke. However, evidence supporting the reliability of these measures is limited. This brief report provides a secondary analysis investigating the between-session reliability of isometric ankle dorsiflexor muscle strength, rate of force development (RFD), and tibialis anterior electromyography (TA EMG), in people with chronic stroke.

Method

Participants (n=15) completed three maximal isometric contractions of the ankle dorsiflexor muscles as fast as possible using a rigid dynamometer. Tests were repeated seven days later. Outcomes included ankle dorsiflexor isometric maximal voluntary contraction (MVC), RFD in the first 200ms (RFD200ms), time to reach 90% MVC, and peak TA EMG. Data were analysed for 13 participants using intra-class correlation coefficients (ICC) and standard error of the measure percentage (SEM%).

Results

Reliability was higher when analysing the mean of three trials rather than the best of three trials. There was excellent reliability for isometric dorsiflexor MVC (ICC 0.97 [95% CI 0.92, 0.99], SEM% 7%). However, for other outcomes, while the ICC indicated good reliability, the lower bound of the 95% confidence interval of the ICC fell in the moderate range for TA EMG (ICC 0.86 [95% CI 0.60, 0.96], SEM% 25%) and time to reach 90% MVC (ICC 0.8 [95% CI 0.53, 0.93], SEM% 23%) and in the poor range for dorsiflexor RFD200ms (ICC 0.79 [95% CI 0.48, 0.92], SEM% 24%).

Conclusion

The findings raise concerns about the reliability of measures of rapid force production in the dorsiflexor muscles after stroke. Given the functional significance of the ankle dorsiflexors, larger studies should be conducted to further investigate these concerns and explore reliable methods for measuring rapid force production in the hemiparetic dorsiflexor muscles.

Multi-Modal Prehabilitation in Thoracic Surgery: From Basic Concepts to Practical Modalities

Over the last two decades, the invasiveness of thoracic surgery has decreased along with technological advances and better diagnostic tools, whereas the patient's comorbidities and frailty patterns have increased, as well as the number of early cancer stages that could benefit from curative resection. Poor aerobic fitness, nutritional defects, sarcopenia and "toxic" behaviors such as sedentary behavior, smoking and alcohol consumption are modifiable risk factors for major postoperative complications. The process of enhancing patients' physiological reserve in anticipation for surgery is referred to as prehabilitation. Components of prehabilitation programs include optimization of medical treatment, prescription of structured exercise program, correction of nutritional deficits and patient's education to adopt healthier behaviors. All patients may benefit from prehabilitation, which is part of the enhanced recovery after surgery (ERAS) programs. Faster functional recovery is expected in low-risk patients, whereas better clinical outcome and shorter hospital stay have been demonstrated in higher risk and physically unfit patients.

Efficacy of neuromobilization in the treatment of low back pain: Systematic review and meta-analysis

BACKGROUND

Low back pain (LBP) is a leading cause of disability. Neuromobilization (NM) as a physical therapy technique, offers some degree of symptom improvement. However, some studies have shown that NM can significantly reduce the symptoms of LBP, while others have failed to find similar positive effects.

OBJECTIVE

This study aims to investigate the effectiveness of NM for LBP.

DATA SOURCES

A literature search was conducted across five databases (MEDLINE, Embase, Cochrane Library, PubMed, and Web of Science) from their inception to December 2023. Study main measures assessed pain, disability, and straight leg raise angle to determine the degree of improvement in patients.

RESULTS

Seven randomized controlled trials were included in the analysis. The findings indicated that NM interventions in patients with LBP were more effective than control groups in improving Visual Analog Scale scores (mean difference = 0.62, 95% CI (0.03, 1.21)) and Oswestry Disability Index scores (mean difference = 7.54, 95% CI (4.98, 10.10)). There was no significant difference in straight leg raise results (mean difference = 0.18, 95% CI (-0.08, 0.44)).

CONCLUSIONS

NM demonstrated effectiveness in improving Visual Analog Scale and Oswestry Disability Index outcomes in patients with LBP, but straight leg raise outcomes are still uncertain and until more high-quality studies are included, the effectiveness of NM for SLR remains unknown.

Improvements of mid-thigh circumferences following robotic rehabilitation in hemiparetic stroke patients

INTRODUCTION

Stroke has emerged as the leading cause of disability globally. The provision of long-term rehabilitation to stroke survivors poses a health care burden to many countries. Robotic devices have created a major turning point in stroke rehabilitation program. Currently, the anthropometric evidence to support the benefit of robotic rehabilitation (RR) among stroke patients is scarce. Therefore, the aim of this study was to evaluate the impact of RR on the mid-thigh circumferences of the paretic limbs in stroke patients.

METHODS

Twenty stroke patients from conventional rehabilitation (CR) (n = 10) and RR (n = 10) groups were recruited through a purposive sampling method. Patients in the CR group received a two-hour session of a five-day-a-week home-based CR program for 4 weeks. Patients in the RR group received a five-day-a-week of an hour combined physiotherapy and occupational therapy session and a one-hour robotic therapy session using the HAL® Cyberdyne lower-limb, for 4 weeks. The mid-thigh circumferences of both limbs were measured on day 1 (baseline), week 2 and week 4 of rehabilitation program.

RESULTS

The results revealed no statistically significant difference in the mid-thigh circumferences between the paretic (F1.05,9.44 = 1.96, p = 0.20), and the normal (F1.05,9.44 = 1.96, p = 0.20) sides in the CR group (n = 10). For the comparison between the paretic and normal sides in the RR group (n = 10), the paretic mid-thigh circumferences revealed significant time effect results (F2,18 = 11.91, p = 0.001), which were due to changes between baseline and week 2, and baseline and week 4 measurements. Interestingly, the normal mid-thigh circumferences also revealed a significant time effect (F2,18 = 6.56, p = 0.007), which is due to changes between baseline and week 4. One-way analysis of variance was employed to compare the mean average between groups due to the difference in the baseline measurements of the mid-thigh circumferences between the paretic side of the CR and the RR groups. With this adjustment, the average means mid-thigh circumferences after 4 weeks of therapy were shown to be significantly different between the CR and RR groups (F1,18 = 12.49, p = 0.02).

CONCLUSION

Significant increments in the mid-thigh circumferences following RR were seen in the paretic limbs of stroke patients. Hence, this study may provide some insights into further potential research related to the benefits of RR in stroke patients.

Effects of non-invasive cervical spinal cord neuromodulation by trans-spinal electrical stimulation on cortico-muscular descending patterns in upper extremity of chronic stroke

Background: Trans-spinal electrical stimulation (tsES) to the intact spinal cord poststroke may modulate the cortico-muscular control in stroke survivors with diverse lesions in the brain. This work aimed to investigate the immediate effects of tsES on the cortico-muscular descending patterns during voluntary upper extremity (UE) muscle contractions by analyzing cortico-muscular coherence (CMCoh) and electromyography (EMG) in people with chronic stroke. Methods: Twelve chronic stroke participants were recruited to perform wrist-hand extension and flexion tasks at submaximal levels of voluntary contraction for the corresponding agonist flexors and extensors. During the tasks, the tsES was delivered to the cervical spinal cord with rectangular biphasic pulses. Electroencephalography (EEG) data were collected from the sensorimotor cortex, and the EMG data were recorded from both distal and proximal UE muscles. The CMCoh, laterality index (LI) of the peak CMCoh, and EMG activation level parameters under both non-tsES and tsES conditions were compared to evaluate the immediate effects of tsES on the cortico-muscular descending pathway. Results: The CMCoh and LI of peak CMCoh in the agonist distal muscles showed significant increases (p < 0.05) during the wrist-hand extension and flexion tasks with the application of tsES. The EMG activation levels of the antagonist distal muscle during wrist-hand extension were significantly decreased (p < 0.05) with tsES. Additionally, the proximal UE muscles exhibited significant decreases (p < 0.05) in peak CMCoh and EMG activation levels by applying tsES. There was a significant increase (p < 0.05) in LI of peak CMCoh of proximal UE muscles during tsES. Conclusion: The cervical spinal cord neuromodulation via tsES enhanced the residual descending excitatory control, activated the local inhibitory circuits within the spinal cord, and reduced the cortical and proximal muscular compensatory effects. These results suggested the potential of tsES as a supplementary input for improving UE motor functions in stroke rehabilitation.

Effects of eccentric strength training on motor function in individuals with stroke: a scoping review

BACKGROUND

Preliminary evidence suggests that eccentric strength training (ECC) improves muscle strength and postural control in individuals with stroke; however, the evidence about the effects of ECC in people living with stroke has not been systematically analyzed.

OBJECTIVE

To determine the effects of ECC, compared to other exercise modalities (i.e., concentric training), on motor function in individuals with stroke.

METHODS

This scoping review was performed according to PRISMA extension for scoping reviews. Until March 2023, a comprehensive search of studies using ECC intervention to improve motor functions in individuals with stroke was performed. Study designs included were randomized and non-randomized controlled trials and quasi-experimental studies using MEDLINE, Web of Science, Rehabilitation & Sports Medicine, PEDro, and OTSeeker databases. Two independent reviewers selected articles based on title and abstract and extracted relevant information from the eligible studies. The results were qualitatively synthesized, and the critical appraisal was performed using the Rob 2.0 and Robins-I tools.

RESULTS

Ten studies, with 257 individuals, were analyzed. ECC revealed positive effects on muscle strength, muscular activity, balance, gait speed, and functionality, mainly compared with concentric training, physical therapy, and daily routine. No significant adverse events were reported during ECC. The critical appraisal of individual articles ranged from some to high concern.

CONCLUSION

ECC had a greater and positive effect on motor function in individuals with stroke than other exercise modalities. However, the limited number of studies, variability of outcomes, and the risk of bias produced a low certainty of evidence.

Spatial distribution of stiffness between and within muscles in paretic and healthy individuals during prone and standing positions

This study investigated the inter- and intramuscular variability of plantar flexors stiffness during prone and standing positions at different muscle lengths in healthy and paretic individuals. To access tissue stiffness, shear wave elastography (SWE) measurements were carried out on two groups: control group (CG; n=14; age 43.9±9.6 years; body mass index [BMI]=24.5±2.5 kg/m2) and stroke survivor group (SSG; n=14; age 43.9±9.6 years; BMI=24.5±2.5 kg/m2). Shear Modulus (μ, kPa) within three plantar flexors (the gastrocnemius medialis [GM], gastrocnemius lateralis [GL], and soleus [SOL]) was obtained during two conditions: prone and standing position, at different angles of dorsiflexion (0°, 10°, and 20°). Measurements were also performed in different proximo-distal regions of each muscle. Muscle activation of the GM, GL, SOL, and tibialis anterior were evaluated during the two conditions. Results showed a high spatial stiffness variability between and within plantar flexors during dorsiflexion. The highest stiffness was observed in the GM, especially in the distal region at 20° in healthy and paretic muscles. In the prone position, the paretic muscle exhibits greater stiffness compared to the healthy muscle (p < 0.05). In contrast, in the standing position, an increase of stiffness in the healthy muscle compared to the paretic muscle was observed (p < 0.05). Thus, mechanical properties are differently affected by stroke depending on active and passive states of ankle muscles during dorsiflexion. In addition, the modification of ankle muscle state change stiffness distribution between and within plantar flexors.

Management of Upper-Limb Spasticity Using Modern Rehabilitation Techniques versus Botulinum Toxin Injections Following Stroke

Our purpose is to emphasize the role of botulinum toxin in spasticity therapy and functional recovery in patients following strokes. Our retrospective study compared two groups, namely ischemic and hemorrhagic stroke patients. The study group (BT group) comprised 80 patients who received focal botulinum toxin as therapy for an upper limb with spastic muscle three times every three months. The control group (ES group) comprised 80 patients who received only medical rehabilitation consisting of electrostimulation and radial shockwave therapy for the upper limb, which was applied three times every three months. Both groups received the same stretching program for spastic muscles as a home training program. We evaluated the evolution of the patients using muscle strength, Ashworth, Tardieu, Frenchay, and Barthel scales. The analysis indicated a statistically significant difference between the two groups for all scales, with better results for the BT group (p < 0.0001 for all scales). In our study, the age at disease onset was an important prediction factor for better recovery in both groups but not in all scales. Better recovery was obtained for younger patients (in the BT group, MRC scale: rho = -0.609, p-value < 0.0001; Tardieu scale: rho = -0.365, p-value = 0.001; in the ES group, MRC scale: rho = -0.445, p-value < 0.0001; Barthel scale: rho = -0.239, p-value = 0.033). Our results demonstrated the effectiveness of botulinum toxin therapy compared with the rehabilitation method, showing a reduction of the recovery time of the upper limb, as well as an improvement of functionality and a reduction of disability. Although all patients followed a specific kinetic program, important improvements were evident in the botulinum toxin group.

Assessing Stroke-Related Sarcopenia in Chronic Stroke: Identification of Clinical Assessment Tools-A Pilot Study

Stroke-related sarcopenia has recently been defined as the muscle atrophy consequent to stroke and assessing it following the guidelines with simple clinical tools is crucial in chronic stroke survivors. The aim of this study was to determine the characteristics of patient-friendly instruments sarcopenia in a chronic stroke sample (SG) compared to non-stroke counterparts (CG). Each participant underwent a single assessment which consisted of: SARC-F questionnaire, assessment of muscle strength (hand grip and five-times sit-to-stand test, 5STS), the calf circumference (CC) of both legs, the short physical performance battery (SPPB), and the 10 m walk test. A total of 68 participants were included (SG, n = 34 and CG, n = 34). All variables showed statistical differences (p < 0.05) between the SG and the CG, except handgrip although it showed lower values for SG. The values of the 5STS (16.26 s) and the SPPB (7 points) were below to the cutoff values for the SG. The five-times sit-to-stand test, SPPB, and gait speed can lead clinicians to detect stroke-related sarcopenia. Maximum handgrip shows a trend of low values for men and women in the SG, however, CC did not detect sarcopenia in our sample.

Empirical Myoelectric Feature Extraction and Pattern Recognition in Hemiplegic Distal Movement Decoding

In myoelectrical pattern recognition (PR), the feature extraction methods for stroke-oriented applications are challenging and remain discordant due to a lack of hemiplegic data and limited knowledge of skeletomuscular function. Additionally, technical and clinical barriers create the need for robust, subject-independent feature generation while using supervised learning (SL). To the best of our knowledge, we are the first study to investigate the brute-force analysis of individual and combinational feature vectors for acute stroke gesture recognition using surface electromyography (EMG) of 19 patients. Moreover, post-brute-force singular vectors were concatenated via a Fibonacci-like spiral net ranking as a novel, broadly applicable concept for feature selection. This semi-brute-force navigated amalgamation in linkage (SNAiL) of EMG features revealed an explicit classification rate performance advantage of 10-17% compared to canonical feature sets, which can drastically extend PR capabilities in biosignal processing.

Effects of Exercise Training on Muscle Quality in Older Individuals: A Systematic Scoping Review with Meta-Analyses

BACKGROUND

The quantity and quality of skeletal muscle are important determinants of daily function and metabolic health. Various forms of physical exercise can improve muscle function, but this effect can be inconsistent and has not been systematically examined across the health-neurological disease continuum. The purpose of this systematic scoping review with meta-analyses was to determine the effects and potential moderators of exercise training on morphological and neuromuscular muscle quality (MMQ, NMQ) in healthy older individuals. In addition and in the form of a scoping review, we examined the effects of exercise training on NMQ and MMQ in individuals with neurological conditions.

METHODS

A systematic literature search was performed in the electronic databases Medline, Embase, and Web of Science. Randomized controlled trials were included that examined the effects of exercise training on muscle quality (MQ) in older individuals with and without neurological conditions. Risk of bias and study quality were assessed (Cochrane Risk of Bias Tool 2.0). We performed random-effects models using robust variance estimation and tested moderators using the approximate Hotelling-Zhang test.

RESULTS

Thirty studies (n = 1494, 34% females) in healthy older individuals and no studies in individuals with neurological conditions were eligible for inclusion. Exercise training had small effects on MMQ (g = 0.21, 95% confidence interval [CI]: 0.03-0.40, p = 0.029). Heterogeneity was low (median I² = 16%). Training and demographic variables did not moderate the effects of exercise on MMQ. There was no association between changes in MMQ and changes in functional outcomes. Exercise training improved NMQ (g = 0.68, 95% CI 0.35-1.01, p < 0.000) across all studies, in particular in higher-functioning older individuals (g = 0.72, 95% CI 0.38-1.06, p < 0.001), in lower extremity muscles (g = 0.74, 95% CI 0.35-1.13, p = 0.001), and after resistance training (g = 0.91; 95% CI 0.42-1.41, p = 0.001). Heterogeneity was very high (median I² = 79%). Of the training and demographic variables, only resistance training moderated the exercise-effects on NMQ. High- versus low-intensity exercise moderated the exercise-effects on NMQ, but these effects were considered unreliable due to a low number of studies at high intensity. There was no association between changes in NMQ and changes in functional outcomes.

CONCLUSION

Exercise training has small effects on MMQ and medium-large effects on NMQ in healthy older individuals. There was no association between improvements in MQ and increases in muscle strength, mobility, and balance. Information on dose-response relations following training is currently lacking. There is a critical gap in muscle quality data for older individuals with lower function and neurological conditions after exercise training. Health practitioners should use resistance training to improve muscle function in older individuals. Well-designed studies are needed to examine the relevance of exercise training-induced changes in MQ in daily function in older individuals, especially to those with lower function and neurological conditions.

Effects of Home-Based Boxing Training on Trunk Performance, Balance, and Enjoyment of Patients With Chronic Stroke

OBJECTIVE

To investigate the effect of 6 weeks of home-based boxing training on trunk performance, balance, fear of falling, and level of therapy enjoyment in individuals with chronic stroke.

METHODS

Eighteen participants with chronic stroke were randomly divided into boxing and control groups (9 patients per group). The boxing group received home-based boxing training for 25 minutes plus balance and trunk exercise training for 15 minutes, while the control group received only home-based balance and trunk exercise training for 40 minutes, three days a week for 6 weeks. The Trunk Impairment Scale (TIS), Mini-Balance Evaluation Systems Test (Mini-BESTest), Activities-specific Balance Confidence (ABC) scale, and Physical Activity Enjoyment Scale (PACES) were assessed at baseline, and at 2, 4, and 6 weeks post-training. The Wilcoxon signed rank test and Mann-Whitney U-test were used to determine differences between pre- and post-training within and between groups. Statistical significance was set at p<0.05.

RESULTS

The TIS scores significantly increased from 13 to 17 points in the boxing group (p<0.05) compared to an increase from 15 to 17 points in the control group (p<0.05). The Mini-BESTest scores significantly increased from 14 to 22 points in the boxing group (p<0.05) compared to an increase from 17 to 20 points in the control group (p<0.05). There were no differences in the TIS, Mini-BESTest, ABC, and PACES scores between the two groups.

CONCLUSION

Home-based boxing training with balance and trunk exercise training had a similar training effect compared to home-based balance and trunk exercise training.

Ultrasound Assessment of Spastic Muscles in Ambulatory Chronic Stroke Survivors Reveals Function-Dependent Changes

OBJECTIVE

To correlate ultrasound characteristics of spastic muscles with clinical and functional measurements in chronic stroke survivors.

METHODS

Ultrasound assessment and clinical and functional assessments were performed in 28 ambulatory stroke survivors (12 females, mean age 57.8 ± 11.8 years, 76 ± 45 months after stroke).

RESULTS

Muscle thickness in the affected side was decreased compared with the contralateral side (p < 0.001). The decrease was more evident in the upper limb muscles. On the affected side, the modified Heckmatt scale score was lowest (closer to normal) in the rectus femoris (RF) muscle compared with other muscles (biceps brachii (BB), flexor carpi ulnaris (FCU) and medial gastrocnemius (MG)). Muscle thickness and echogenicity of spastic muscles did not correlate with spasticity, as measured with the modified Ashworth scale (MAS), Fugl-Meyer motor assessment scores, age, or time since stroke. There was a significant negative correlation between grip strength and percentage decrease in muscle thickness for the spastic FCU muscle (r = -0.49, p = 0.008). RF muscle thickness correlated with ambulatory function (Timed Up and Go test (r = 0.44, p = 0.021) and 6-metre walk test (r = 0.41, p = 0.032)). There was no significant correlation between echogenicity and functional assessments Conclusion: Ambulatory chronic stroke survivors had function-dependent changes in muscle thickness on the affected side. Muscle thickness and echogenicity of spastic muscles did not correlate with spasticity, Fugl-Meyer motor assessment scores, age, or time since stroke.

Upper Limbs Muscle Co-contraction Changes Correlated With the Impairment of the Corticospinal Tract in Stroke Survivors: Preliminary Evidence From Electromyography and Motor-Evoked Potential

Objective

Increased muscle co-contraction of the agonist and antagonist muscles during voluntary movement is commonly observed in the upper limbs of stroke survivors. Much remain to be understood about the underlying mechanism. The aim of the study is to investigate the correlation between increased muscle co-contraction and the function of the corticospinal tract (CST).

Methods

Nine stroke survivors and nine age-matched healthy individuals were recruited. All the participants were instructed to perform isometric maximal voluntary contraction (MVC) and horizontal task which consist of sponge grasp, horizontal transportation, and sponge release. We recorded electromyography (EMG) activities from four muscle groups during the MVC test and horizontal task in the upper limbs of stroke survivors. The muscle groups consist of extensor digitorum (ED), flexor digitorum (FD), triceps brachii (TRI), and biceps brachii (BIC). The root mean square (RMS) of EMG was applied to assess the muscle activation during horizontal task. We adopted a co-contraction index (CI) to evaluate the degree of muscle co-contraction. CST function was evaluated by the motor-evoked potential (MEP) parameters, including resting motor threshold, amplitude, latency, and central motor conduction time. We employed correlation analysis to probe the association between CI and MEP parameters.

Results

The RMS, CI, and MEP parameters on the affected side showed significant difference compared with the unaffected side of stroke survivors and the healthy group. The result of correlation analysis showed that CI was significantly correlated with MEP parameters in stroke survivors.

Conclusion

There existed increased muscle co-contraction and impairment in CST functionality on the affected side of stroke survivors. The increased muscle co-contraction was correlated with the impairment of the CST. Intervention that could improve the excitability of the CST may contribute to the recovery of muscle discoordination in the upper limbs of stroke survivors.

Do Muscle Changes Contribute to the Neurological Disorder in Spastic Paresis?

Background

At the onset of stroke-induced hemiparesis, muscle tissue is normal and motoneurones are not overactive. Muscle contracture and motoneuronal overactivity then develop. Motor command impairments are classically attributed to the neurological lesion, but the role played by muscle changes has not been investigated.

Methods

Interaction between muscle and command disorders was explored using quantified clinical methodology-the Five Step Assessment. Six key muscles of each of the lower and upper limbs in adults with chronic poststroke hemiparesis were examined by a single investigator, measuring the angle of arrest with slow muscle stretch (XV1) and the maximal active range of motion against the resistance of the tested muscle (XA). The coefficient of shortening CSH = (XN-XV1)/XN (XN, normally expected amplitude) and of weakness CW = (XV1-XA)/XV1) were calculated to estimate the muscle and command disorders, respectively. Composite CSH (CCSH) and CW (CCW) were then derived for each limb by averaging the six corresponding coefficients. For the shortened muscles of each limb (mean CSH > 0.10), linear regressions explored the relationships between coefficients of shortening and weakness below and above their median coefficient of shortening.

Results

A total of 80 persons with chronic hemiparesis with complete lower limb assessments [27 women, mean age 47 (SD 17), time since lesion 8.8 (7.2) years], and 32 with upper limb assessments [18 women, age 32 (15), time since lesion 6.4 (9.3) years] were identified. The composite coefficient of shortening was greater in the lower than in the upper limb (0.12 ± 0.04 vs. 0.08 ± 0.04; p = 0.0002, while the composite coefficient of weakness was greater in the upper limb (0.28 ± 0.12 vs. 0.15 ± 0.06, lower limb; p < 0.0001). In the lower limb shortened muscles, the coefficient of weakness correlated with the composite coefficient of shortening above the 0.15 median CSH (R = 0.43, p = 0.004) but not below (R = 0.14, p = 0.40).

Conclusion

In chronic hemiparesis, muscle shortening affects the lower limb particularly, and, beyond a threshold of severity, may alter descending commands. The latter might occur through chronically increased intramuscular tension, and thereby increased muscle afferent firing and activity-dependent synaptic sensitization at the spinal level.