Muscle Motor Function Research Articles

Performance of Passive Muscle Stiffness in Diagnosis and Assessment of Disease Progression in Duchenne Muscular Dystrophy

The aim of this study was to evaluate the performance of passive muscle stiffness in diagnosing and assessing disease progression in Duchenne muscular dystrophy (DMD). Boys with DMD and age-matched controls were recruited. Shear wave elastography (SWE) videos were collected by performing dynamic stretching of the gastrocnemius medius (GM). At ankle angles from plantar flexion (PF) 30° to dorsiflexion (DF) 20°, the shear modulus of the GM was measured for each 10° of ankle movement. Shear modulus at each ankle angle was compared between the DMD and control group. Correlation between passive muscle stiffness and motor function grading was also analyzed. A total of 26 patients with DMD and 20 healthy boys were enrolled. At multiple stretch levels, passive muscle stiffness of the GM was significantly higher in patients with DMD than in those in the control group (all p values <0.05). The shear modulus of GM at an ankle angle of DF 10° had the largest area under the receiver operating characteristic curve in differentiating DMD patients from normal subjects (AUC = 0.902, 95% confidence interval: 0.814-0.990). Motor function grading was a significant determinant of passive muscle stiffness at an ankle angle of DF 10° (B = 21.409, t = 3.372, p = 0.003). Passive muscle stiffness may potentially serve as a useful non-invasive tool to monitor disease progression in DMD patients.

EMG-Triggered Pedaling Training on Muscle Activation, Gait, and Motor Function for Stroke Patients.

This study aimed to determine the effects of electromyography (EMG)-triggered pedaling training to improve motor functions in the lower extremities, muscle activation, gait, postural balance, and activities of daily living in stroke patients. Subjects were randomly allocated to two groups: the EMG-triggered pedaling training group (EMG-PTG, n = 21) and the traditional pedaling training group (TPTG, n = 20). Both groups trained five times per week for four weeks, with 50 min per session. Lower extremity motor function was assessed using the Fugl–Meyer Assessment (FMA). Muscle activation of the four muscles of the lower extremities was assessed using eight-channel electromyography, while gait ability was assessed using GaitRite. Postural balance was assessed using the Berg balance scale (BBS), the timed up and go (TUG), and functional reach tests (FRT). Daily activities were assessed using the Modified Barthel Index (MBI). For lower extremity motor function, gait ability, balance ability, and activities of daily living, the EMG-PTG showed significant improvement compared to TPTG (p < 0.05). These results suggest that EMG-triggered pedaling training effectively improves lower extremity motor function, muscle activation, gait, postural balance, and activities of daily living in stroke patients.

Inter-muscular coherence and functional coordination in the human upper extremity after stroke

&lt;abstract&gt;&lt;p&gt;Muscle coordination and motor function of stroke patients are weakened by stroke-related motor impairments. Our earlier studies have determined alterations in inter-muscular coordination patterns (muscle synergies). However, the functional connectivity of these synergistically paired or unpaired muscles is still unclear in stroke patients. The goal of this study is to quantify the alterations of inter-muscular coherence (IMC) among upper extremity muscles that have been shown to be synergistically or non-synergistically activated in stroke survivors. In a three-dimensional isometric force matching task, surface EMG signals are collected from 6 age-matched, neurologically intact healthy subjects and 10 stroke patients, while the target force space is divided into 8 subspaces. According to the results of muscle synergy identification with non-negative matrix factorization algorithm, muscle pairs are classified as synergistic and non-synergistic. In both control and stroke groups, IMC is then calculated for all available muscle pairs. The results show that synergistic muscle pairs have higher coherence in both groups. Furthermore, anterior and middle deltoids, identified as synergistic muscles in both groups, exhibited significantly weaker IMC at alpha band in stroke patients. The anterior and posterior deltoids, identified as synergistic muscles only in stroke patients, revealed significantly higher IMC in stroke group at low gamma band. On the contrary, anterior deltoid and pectoralis major, identified as synergistic muscles in control group only, revealed significantly higher IMC in control group in alpha band. The results of muscle synergy and IMC analyses provide congruent and complementary information for investigating the mechanism that underlies post-stroke motor recovery.&lt;/p&gt;&lt;/abstract&gt;

Metric-Based Muscle Synergy Consistency for Upper Limb Motor Functions

The hypothesis of muscle synergy has been dominantly accepted in research due to the evidence of being well investigated its existence in multiple disciplines, such as health science. Motor function assessment using muscle synergy provides a quantitative approach from the physiological features of muscles. Given the synergy coordinating multiple muscles in a natural motion, this article proposes a surface electromyography (sEMG)-driven metric to measure the consistency of the muscle synergy patterns of upper limb motor functions. The metric-based consistency algorithm primarily comprises three stages: 1) to construct nonnegative matrix factorization (NNMF)-based sEMG muscle synergy patterns; 2) to validate synergy similarities via cosine similarity; and 3) to conduct the patterns consistency between motion cycles checking via the Mahalanobis distance (MD). The proposed measure is employed to validate synergy consistency in upper limb motor function of isokinetic movement protocols involving ten subjects. The muscle synergy similarity has achieved averages of 88&#x0025; and 97&#x0025; for intersubject and intrasubject, respectively. The synergy consistency via MD is significantly positively correlated with the maximum joint torque fluctuation between motion cycles to indicate its efficiency. This quantitative measurement confirms that muscle synergy can be used to measure muscle motor function, paving the way for motion protocol assessment, such as stroke rehabilitation and exercise-induced muscle injury avoidance through monitoring the consistency of the linear combination of muscle activations during movement.

Effects of 1 Hz Low Frequency Repetitive Transcranial Magnetic Stimulation with Neuromuscular Electrical Stimulation Applied to Contralateral Cerebral Cortex on Muscle Activity, Muscle Tone and Upper Limb Motor Function in Stroke Patients

This study was to investigate effects of NMES with 1 Hz low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) applied to unaffected cerebral cortex on muscle activities, tone, and motor function of upper limb (UL) in stroke patients. 16 patients were randomly divided into two groups, and experimental group (EG) was subjected to 1 Hz LF-rTMS and neuromuscular electrical stimulation (NMES). In control group (CG), Facilitation of hand intrinsic muscles and NMES were performed. It was evaluated using electromyography (EEG), MyotonePRO, and Fugl-Meyer assessment (FMA). As a result, there were significant differences on EMG of the anterior deltoid, triceps brachii (TB), MyotonePRO, and FMA in the EG. CG showed a significant difference in EMG of TB. Between groups, there was a significant difference in the biceps brachii and TB. It’s thought that 1 Hz LF-rTMS and NMES can have a positive effect to improve muscle activity and UL in stroke patients.

A Novel and Clinically Feasible Instrument for Quantifying Upper Limb Muscle Tone and Motor Function via Indirect Measure Methods.

Objective: Quantifying muscle tone is often based on a tester’s subjective judgment in clinical settings. There is, however, a lack of suitable tools that can be used to objectively assess muscle tone. This study thus introduces a reliable, clinically-feasible device, called the Arm Circumference Motor Evaluation System (ACMES), for quantifying the muscle tone of upper limbs without using mechanical torque transducers. Methods: While the ACMES conducts continuously passive arm circumduction motions, the voltage and current of the driving motor is transduced into torque values via a least square approximation. A torque sensor and springs with different spring constants were used for the validity and reliability test in the first part of this study. Fifteen healthy adults and two patients who had experienced a stroke participated in the second part, which was a clinical experiment used to examine the in-vivo test-retest reliability and to explore the inspection differences between healthy and patient participants. Results: The results showed that the ACMES has high validity (R2: ~0.99) and reliability (R2: 0.96~0.99). The reliability of the ACMES used on human subjects was acceptable (R2: 0.83~0.85). The various muscle tone patterns could be found among healthy and stroke subjects via the ACMES. Conclusion: Clinically, abnormal muscle tone, which seriously affects motion performance, will be found in many diagnoses, such as stroke or cerebral palsy. However, objectively and feasibly measuring abnormal tone in modern clinical settings is still a challenging task. Thus, the ACMES was developed and tested to verify its feasibility as a measurement system for detecting the mechanical torque associated with muscle tone.

KLF15 overexpression in myocytes fails to ameliorate ALS-related pathology or extend the lifespan of SOD1G93A mice

Amyotrophic Lateral Sclerosis (ALS) is a currently incurable disease that causes progressive motor neuron loss, paralysis and death. Skeletal muscle pathology occurs early during the course of ALS. It is characterized by impaired mitochondrial biogenesis, metabolic dysfunction and deterioration of the neuromuscular junction (NMJ), the synapse through which motor neurons communicate with muscles. Therefore, a better understanding of the molecules that underlie this pathology may lead to therapies that slow motor neuron loss and delay ALS progression. Kruppel Like Factor 15 (KLF15) has been identified as a transcription factor that activates alternative metabolic pathways and NMJ maintenance factors, including Fibroblast Growth Factor Binding Protein 1 (FGFBP1), in skeletal myocytes. In this capacity, KLF15 has been shown to play a protective role in Duchenne muscular dystrophy (DMD) and spinal muscular atrophy (SMA), however its role in ALS has not been evaluated. Here, we examined whether muscle-specific KLF15 overexpression promotes the health of skeletal muscles and NMJs in the SOD1G93A ALS mouse model. We show that muscle-specific KLF15 overexpression did not elicit a significant beneficial effect on skeletal muscle atrophy, NMJ health, motor function, or survival in SOD1G93A ALS mice. Our findings suggest that, unlike in mouse models of DMD and SMA, KLF15 overexpression has a minimal impact on ALS disease progression in SOD1G93A mice.

Design and Assist-as-Needed Control of Flexible Elbow Exoskeleton Actuated by Nonlinear Series Elastic Cable Driven Mechanism

Exoskeletons can assist the daily life activities of the elderly with weakened muscle strength, but traditional rigid exoskeletons bring parasitic torque to the human joints and easily disturbs the natural movement of the wearer’s upper limbs. Flexible exoskeletons have more natural human-machine interaction, lower weight and cost, and have great application potential. Applying assist force according to the patient’s needs can give full play to the wearer’s remaining muscle strength, which is more conducive to muscle strength training and motor function recovery. In this paper, a design scheme of an elbow exoskeleton driven by flexible antagonistic cable actuators is proposed. The cable actuator is driven by a nonlinear series elastic mechanism, in which the elastic elements simulate the passive elastic properties of human skeletal muscle. Based on an improved elbow musculoskeletal model, the assist torque of exoskeleton is predicted. An assist-as-needed (AAN) control algorithm is proposed for the exoskeleton and experiments are carried out. The experimental results on the experimental platform show that the root mean square error between the predicted assist torque and the actual assist torque is 0.00226 Nm. The wearing experimental results also show that the AAN control method designed in this paper can reduce the activation of biceps brachii effectively when the exoskeleton assist level increases.

Gene Therapy Overexpressing Neuregulin 1 Type I in Combination With Neuregulin 1 Type III Promotes Functional Improvement in the SOD1G93A ALS Mice.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting the neuromuscular system for which currently there is no effective therapy. Motoneuron (MN) degeneration involves several complex mechanisms, including surrounding glial cells and skeletal muscle contributions. Neuregulin 1 (NRG1) is a trophic factor present particularly in MNs and neuromuscular junctions. Our previous studies revealed that gene therapy overexpressing the isoform I (NRG1-I) in skeletal muscles as well as overexpressing the isoform III (NRG1-III) directly in the central nervous system are both effective in preserving MNs in the spinal cord of ALS mice, opening novel therapeutic approaches. In this study, we combined administration of both viral vectors overexpressing NRG1-I in skeletal muscles and NRG1-III in spinal cord of the SOD1G93A mice in order to obtain a synergistic effect. The results showed that the combinatorial gene therapy increased preservation of MNs and of innervated neuromuscular junctions and reduced glial reactivity in the spinal cord of the treated SOD1G93A mice. Moreover, NRG1 isoforms overexpression improved motor function of hindlimb muscles and delayed the onset of clinical disease. However, this combinatory gene therapy did not produce a synergic effect compared with single therapies, suggesting an overlap between NRG1-I and NRG1-III activated pathways and their beneficial effects.

Comparisons of muscle thicknesses, echo intensities, and motor functions between community-dwelling older Japanese adults with and without diabetes

BackgroundIndividuals with diabetes tend to show decreased muscle volume and motor function compared to those without diabetes. Ultrasound is a non-invasive and potentially safe method to assess muscle function in patients with diabetes; however, the characteristics of muscle thickness and quality, measured by ultrasound, in individuals with diabetes are unclear. MethodsThis study included 825 community-dwelling older individuals who underwent the Otassha Study comprehensive health survey. We measured the muscle thicknesses and echo intensities of rectus femoris and vastus intermedius; motor function, assessed using knee extension strength; one-leg standing balance; normal walk; fastest walk; timed up-and-go test; and grip strength. Participants were stratified by sex and categorized into those with and without diabetes. We examined inter-group differences in measured values. ResultsOnly knee extension strength showed significantly lower values in men with diabetes than in those without diabetes. Echo intensities and motor function significantly differed between women with and without diabetes. In adjusted multiple comparisons p values, echo intensities and grip strength significantly differed only in women with diabetes, unlike men with diabetes. Echo intensity of the rectus femoris was significantly higher in women with diabetes than in those without diabetes after adjusting for confounders, but similar to that in men. ConclusionWe observed the deterioration of knee extension strength in men and women with diabetes compared to that in those without diabetes; however, the effects on muscle quality were inconsistent between the sexes. Our study suggested recommending exercise programs, especially for older women with diabetes.

What improvements in levator ani motor function lead to improvement in stress urinary incontinence signs and symptoms in females?

The objectives were to determine whether levator ani muscle (LAM) motor function is associated with female stress urinary incontinence (SUI) severity, and whether changes in LAM motor function induced through pelvic floor muscle training (PFMT) are associated with improvements in SUI signs and symptoms. Pelvic morphology and LAM function were evaluated using ultrasound imaging and manual palpation using the elements of the PERFECT Scheme (Power, Endurance, Repetitions, Fast contractions, Elevation, Co-contraction and Timing) before and after women with SUI underwent a 12-week PFMT intervention. SUI severity was determined subjectively (ICIQ-FLUTS-UI) and objectively (30-min pad test [30MPT]). At baseline (n = 97), less leakage on the 30MPT was weakly associated with higher bladder neck position (ρs = -0.209,p = 0.044), yet with lower LAM function based on the PERFECT Scheme (overall score: ρs = 0.206, p = 0.043; repeated maximum voluntary contractions (MVCs): ρs = 0.203, p = 0.046; power/motor control: ρs = 0.214, p = 0.035). Lower symptom severity (ICIQ-FLUTS-UI) was associated with observed perineal lift during coughing (U = 34.000; p = 0.042). All measures of SUI severity and LAM function were significantly improved after PFMT intervention. Greater improvements in bladder neck elevation during MVC (ρs = -0.261, p = 0.027) and greater reductions in levator plate length during MVC (ρs = 0.292, p = 0.016) were weakly associated with greater reductions in leakage (30MPT), the latter also being associated with more improvement symptoms (ICIQ-FLUTS-UI; ρs = 0.238, p = 0.041). Greater improvement in the ability to repeat MVCs (ρs = 0.303, p = 0.009) was weakly associated with smaller improvements in symptoms (ICIQ-FLUTS-UI). Improvements in bladder neck support and elevation show weak associations with improvement in SUI signs and symptoms. LAM function as measured by the PERFECT Scheme is not associated with SUI severity in women, and improvements in LAM function when measured by the PERFECT Scheme are not associated with improvements in SUI signs and symptoms.

Motor unit number index: A potential electrophysiological biomarker for pediatric spinal muscular atrophy.

In adult spinal muscular atrophy (SMA), the motor unit number index (MUNIX) has been shown to be an useful electrophysiological biomarker. This study evaluated the feasibility and the clinical relevance of using the MUNIX technique for patients with pediatric SMA (Ped-SMA) and correlated MUNIX results with clinical scores. Fourteen patients with type II Ped-SMA (11 females; median age 11 y [interquartile range (IQR), 4.8-17 y]) and 14 controls (nine females; median age 10.75 y [IQR, 6.5-13.4y]) were enrolled and matched by sex, age, height, weight, and body mass index. Clinical examination included manual muscle testing, dynamometry (grasp and pinch), and motor function measure (MFM). The MUNIX technique was evaluated in the abductor digiti minimi (ADM) and abductor pollicis brevis (APB) on two sides when possible. In the patients with Ped-SMA, the MUNIX and compound muscle action potential (CMAP) amplitudes were significantly decreased and the motor size unit index (MUSIX) was significantly increased in the ADM and APB when compared to controls. The intraclass correlation coefficient was good for the intrarater variability of the CMAP amplitude, MUNIX, and MUSIX in the ADM (0.95, 0.83, and 0.89, respectively) and the APB (0.98, 0.96, and 0.94, respectively). The total CMAP amplitude correlated with the grasp and pinch scores (P< .05), and the MUNIX measurements correlated with the MFM scores. The MUNIX technique, which accurately estimated lower motor neuron loss and the number of remaining functional motor units, was shown to be a useful electrophysiological biomarker for disease progression and a potential biomarker for treatment response.

Prediction of Long-Term Elbow Flexion Force Intervals Based on the Informer Model and Electromyography

Accurate and long-term prediction of elbow flexion force can be used to recognize the intended movement and help wearable power-assisted robots to improve control performance. Our study aimed to find a proper relationship between electromyography and flexion force. However, the existing methods must incorporate biomechanical models to produce accurate and timely predictions of flexion force. Elbow flexion force is largely determined by the contractile properties of muscles, and the relationship between flexion force and the motor function of muscles has to be thoroughly analyzed. Therefore, based on the investigation on the contributions of different muscles to the flexion force, original electromyography signals were decomposed into non-linear and non-stationary parts. We selected the mean absolute value (MAV) of the non-linear part and the variance of the non-stationary part as inputs for an Informer prediction model that does not require detailed a priori knowledge of biomechanical models and is optimized for processing time sequences. Finally, a long-term flexion force probability interval is proposed. The proposed framework performs well in predicting long-term flexion force and outperforms other state-of-the-art models when compared to experimental results.

Yin-yang penetrating acupuncture with elongated needle for spastic limb dysfunction after stroke: a randomized controlled trial

To compare the clinical effect between yin-yang penetrating acupuncture with elongated needle and routine acupuncture for spastic limb dysfunction after stroke. A total of 60 patients were randomized into an observation group and a control group, 30 cases in each group. Both groups received basic treatment, yin-yang penetrating acupuncture with elongated needle was applied from Yanglingquan (GB 34) to Xuanzhong (GB 39), Quchi (LI 11) to Wenliu (LI 7), Huantiao (GB 30) to Fengshi (GB 31), Jianyu (LI 15) to Quchi (LI 11), etc. on the affected side in the observation group; routine acupuncture was applied at Neiguan (PC 6), Shuigou (GV 26), Sanyinjiao (SP 6), Jiquan (HT 1), Chize (LU 5), Weizhong (BL 40), Jianyu (LI 15), etc. on the affected side in the control group. Once a day, 5 times a week, 2 weeks as a course, 2 courses were required in the two groups. Before and after treatment，the modified Ashworth scale (MAS) grade, Fugl-Meyer assessment scale (FMA) score, activity of daily living scale (ADL) (Barthel index) score were observed, and the clinical effect was evaluated in the two groups. Compared before treatment, the MAS grade after treatment was improved in the two groups (P<0.05), that in the observation group was superior to the control group (P<0.05). Compared before treatment, the FMA and ADL scores after treatment were increased in the two groups (P<0.05), the changes in the observation group were larger than the control group (P<0.05). The total effective rate in the observation group was 80.0% (24/30), which was superior to 70.0% (21/30) in the control group (P<0.05). Yin-yang penetrating acupuncture with elongated needle could improve muscle tension, spasm grade and motor function in patients with spastic limb dysfunction after stroke, enhance the activity of daily living, its clinical effect is superior to routine acupuncture.

Older Compared With Younger Adults Performed 467 Fewer Sit-to-Stand Trials, Accompanied by Small Changes in Muscle Activation and Voluntary Force.

Background: Repetitive sit-to-stand (rSTS) is a fatigue perturbation model to examine the age-effects on adaptability in posture and gait, yet the age-effects on muscle activation during rSTS per se are unclear. We examined the effects of age and exhaustive rSTS on muscle activation magnitude, onset, and duration during ascent and descent phases of the STS task.Methods: Healthy older (n = 12) and younger (n = 11) adults performed rSTS, at a controlled frequency dictated by a metronome (2 s for cycle), to failure or for 30 min. We assessed muscle activation magnitude, onset, and duration of plantar flexors, dorsiflexors, knee flexors, knee extensors, and hip stabilizers during the initial and late stages of rSTS. Before and after rSTS, we measured maximal voluntary isometric knee extension force, and rate of perceived exertion, which was also recorded during rSTS task.Results: Older vs. younger adults generated 35% lower maximum voluntary isometric knee extension force. During the initial stage of rSTS, older vs. younger adults activated the dorsiflexor 60% higher, all 5 muscle groups 37% longer, and the hip stabilizers 80% earlier. Older vs. younger adults completed 467 fewer STS trials and, at failure, their rate of perceived exertion was ~17 of 20 on the Borg scale. At the end of the rSTS, maximum voluntary isometric knee extension force decreased 16% similarly in older and younger, as well as the similar age groups decline in activation of the dorsiflexor and knee extensor muscles (all p < 0.05).Conclusion: By performing 467 fewer STS trials, older adults minimized the potential effects of fatigability on muscle activation, voluntary force, and motor function. Such a sparing effect may explain the minimal changes in gait after rSTS reported in previous studies, suggesting a limited scope of this perturbation model to probe age-effects on muscle adaptation in functional tasks.

Survival motor neuron deficiency slows myoblast fusion through reduced myomaker and myomixer expression.

BackgroundSpinal muscular atrophy is an inherited neurodegenerative disease caused by insufficient levels of the survival motor neuron (SMN) protein. Recently approved treatments aimed at increasing SMN protein levels have dramatically improved patient survival and have altered the disease landscape. While restoring SMN levels slows motor neuron loss, many patients continue to have smaller muscles and do not achieve normal motor milestones. While timing of treatment is important, it remains unclear why SMN restoration is insufficient to fully restore muscle size and function. We and others have shown that SMN‐deficient muscle precursor cells fail to efficiently fuse into myotubes. However, the role of SMN in myoblast fusion is not known.MethodsIn this study, we show that SMN‐deficient myoblasts readily fuse with wild‐type myoblasts, demonstrating fusion competency. Conditioned media from wild type differentiating myoblasts do not rescue the fusion deficit of SMN‐deficient cells, suggesting that compromised fusion may primarily be a result of altered membrane dynamics at the cell surface. Transcriptome profiling of skeletal muscle from SMN‐deficient mice revealed altered expression of cell surface fusion molecules. Finally, using cell and mouse models, we investigate if myoblast fusion can be rescued in SMN‐deficient myoblast and improve the muscle pathology in SMA mice.ResultsWe found reduced expression of the muscle fusion proteins myomaker (P = 0.0060) and myomixer (P = 0.0051) in the muscle of SMA mice. Suppressing SMN expression in C2C12 myoblast cells reduces expression of myomaker (35% reduction; P < 0.0001) and myomixer, also known as myomerger and minion, (30% reduction; P < 0.0001) and restoring SMN levels only partially restores myomaker and myomixer expression. Ectopic expression of myomixer improves myofibre number (55% increase; P = 0.0006) and motor function (35% decrease in righting time; P = 0.0089) in SMA model mice and enhances motor function (82% decrease in righting time; P < 0.0001) and extends survival (28% increase; P < 0.01) when administered in combination with an antisense oligonucleotide that increases SMN protein levels.ConclusionsHere, we identified reduced expression of muscle fusion proteins as a key factor in the fusion deficits of SMN‐deficient myoblasts. This discovery provides a novel target to improve SMA muscle pathology and motor function, which in combination with SMN increasing therapy could enhance clinical outcomes for SMA patients.

POS0016 THE EVALUATION OF FUNCTIONAL ABILITIES OF PATIENTS WITH OSTEOPOROTIC VERTEBRAL FRACTURES AS A BASIS FOR REHABILITATION PROGRAMS DEVELOPING

Background:Due to the demand for special rehabilitation programs for patients with osteoporotic vertebral fractures (VFs), it is of interest to study the functional abilities of those patients. The scientific hypothesis suggests that osteoporotic VFs would cause muscle weakness, muscle dysfunction and conditional disturbances.Objectives:to estimate muscle strength, motor function and coordination disorders in patients with VFs in the setting of systemic osteoporosis as a basis for rehabilitation programs developing.Methods:120 patients aged 43−80 with primary osteoporosis were enrolled. Study group comprised of 60 subjects (56 women, 4 men) with at least 1 VF confirmed by X-rays. Control group included 60 subjects (56 women, 4 men) with osteoporosis but without any osteoporotic fracture. The examination program included back muscles tenzodynamometry, balance tests and stabilometry.Results:Muscle strength deficiency was estimated in study group in trunk flexors (TF) — 40.9% and in trunk extensors (TE) — 18.1% with an adequate function of the left lateral flexors (LLF) and in right lateral flexors (RLF). Patients with VFs had the lower muscle strength vs controls of TE (15.64±9.8 vs 27.73±9.9 kg, p=0.00002), TF (14.61±8.98 vs 21.28±8.38 kg, p=0.0006), LLF (13.10±7.2 vs 24.06±8.9 kg, p=0.005) and RLF 13.44±7.43 vs 24.26±7.65 kg, p=0.0003). Patients with VFs lose their balance faster during one-leg-standing test with open eyes (5.0 [1.0; 10.0] vs 7.5 [5.0; 10.5] sec in control group, p=0.03) and with closed eyes (2.0 [0; 3.0] vs 3.5 [3.0; 5.0] sec, p=0.04). Fukuda-Unterberger test showed greater side dislocation in study group — 40° [25; 45] vs controls 30° [10; 45], (p=0.02). According to stabilometry study group was characterized vs control group by lower balance coefficient with open eyes (77.2±7.6 vs 85.7±9.4%, p=0.002) and with closed eyes (67.1±9.8 vs 73.4±9.9%, p=0.03), greater sagittal displacement (6.8 [2.1; 37.7] vs 4.8 [1.8; 10.7] mm, p=0.025) and deviation in the saggital plane (1.2 [-1.07; 1.5] vs -1.2 [-1.5; 1.2] mm, p=0.01), and also less pressure center velocity (9.51±4.4 vs 7.1±2.7 mm/sec, р=0.009).Conclusion:Osteoporotic VFs are associated with reduction of trunk muscles strength and negatively affect static and dynamic balance function that should be taken into account when developing rehabilitation programs for these patients.Disclosure of Interests:None declared.

Neuromuscular taping treatment of diabetic foot: a concept analysis.

The definition of neuromuscular taping (NMT) has yet to be clearly analysed as a possible treatment for diabetic foot. Case studies, theoretical analysis and results of existing research may lead to varying perceptions on the definition of NMT and its possible effects on diabetic foot. This article aims to analyse the definition of the NMT concept and furthermore as a basis for future research development on diabetic foot. The procedure for reference source search include the principal data bases using "neuromuscular taping" and "diabetic foot" keywords for the period of 2010-2019. The concept analysis uses an 8-step approach with the Walker and Avant's method. NMT is a decompression application of an elastic tape on the skin on the diabetic foot that has the effect of reducing the inflammatory response, improving vascularity and neuromusculoskel-etal function. It aims to improve neuromusculoskeletal and lymphatic system functioning due to the presence of wrinkles, indicating dila-tion, with local effects on the sensorimotor and proprioceptive senses in conditions of care, rehabilitation and injury. Analysis of the NMT concept on diabetic foot obtained attributes of elastic tape, skin, pain, edema, injury, sensorimotor, circulation, drainage, relaxation, local, proprioceptive, motion func-tion, strength, contraction, stabilisation, reflex, rehabilitation, care, musculoskeletal, nerve, muscles, tendons, fascia, joints, lymphatic, longitudinal, wrinkles. There were four groups of attributes, namely inflammatory response, vascularity, neuromusculoskeletal function and musculoskeletal system. NMT application benefits for diabetic foot can be attributed to improving walking function, leg position, decreasing pain response, improving body function index, improving leg muscle strength and motor function, increasing range of movement (ROM), maintaining stability of leg joint function, preventing injury, increas-ing strength and improving position of ankle joints, reducing stiffness, reducing edema and helping wound healing processes.

Eight Weeks of High-Intensity Interval Static Strength Training Improves Skeletal Muscle Atrophy and Motor Function in Aged Rats via the PGC-1α/FNDC5/UCP1 Pathway.

BackgroundSarcopenia is a syndrome characterized by the loss of skeletal muscle mass and strength. Most studies have focused on dynamic resistance exercises for preventing muscular decline and maintaining the muscle strength of older individuals. However, this training mode is impractical for older people with osteoarthritis and a limited range of motion. The static strength training mode is more suitable for older people. Therefore, a determination of the effect and mechanism of static strength training on sarcopenia is critical.MethodsIn this study, we developed a training device designed to collect training data and evaluate the effects of static training on the upper limbs of rats. The expression of PGC-1α was locally blocked by injecting a siRNA at the midpoint of the biceps to determine whether PGC-1α signal transduction participates in the effects of high-intensity interval static training on muscle strength. Then, the rat’s motor capacity was measured after static strength training. Immunohistochemistry and Western blotting were applied to determine PGC-1α/FNDC5/UCP1 expression levels in the muscle and adipose tissue. The serum irisin level was also detected using an enzyme-linked immunosorbent assay (ELISA).ResultsIncreased levels of serum irisin and local expression of FNDC5, PGC-1α, and UCP1 were observed in the biceps brachii and surrounding fatty tissue after static strength training. Static strength training showed an advantage in reducing body weight and white fat accumulation while increasing the muscle fiber volume, which resulted in a longer training time and shorter rest time.ConclusionOverall, these results indicated that high-intensity interval static training prevents skeletal muscle atrophy and improves the motor function of aged rats through the PGC-1α/FNDC5/UCP1 signaling pathway.

Perimenopausal women show modulation of excitatory and inhibitory neuromuscular mechanisms

BackgroundMenopausal transition exposes women to an early decline in muscle force and motor function. Changes in muscle quality and function, especially in lower limbs, are crucial, as they expose individuals to increased risk of falls. To elucidate some of the related neuromuscular mechanisms, we investigated cortical inhibition and peripheral muscle twitch force potentiation in women during the early and late stages of perimenopause.MethodsParticipants were 63 women aged 48–55 years categorized as early (EP, n = 25) or late (LP, n = 38) perimenopausal according to serum follicle-stimulating hormone (FSH) levels and menstrual diaries. EP women had an irregular menstrual cycle and FSH < 25 IU/L, while LP women had an irregular cycle and > 25 IU/L. We examined motor evoked potential (MEP) and silent period (SP) elicited by transcranial magnetic stimulation (TMS), in the tibialis anterior muscle at 20%, 40%, and 60% of maximal voluntary contraction (MVC) levels, and twitch force potentiation in plantar flexors.ResultsEP group showed a longer SP duration in 40% MVC condition and larger motor evoked potential amplitude in 20% MVC condition compared to the LP group. No group difference was detected in twitch force potentiation; however, it correlated negatively with FSH levels. Other factors, such as age, height, body mass index, or physical activity did not explain group differences.ConclusionsOur preliminary results indicate subtle modulation in both TMS-induced inhibitory and excitatory mechanisms and twitch force potentiation in women already in the late perimenopausal stage. This suggests that the reduction of estrogens may have an accelerating role in the aging process of neuromuscular control.