Search Results (616)

(1) Background: We developed a novel technology that regulates human locomotion using transcutaneous electrical spinal cord stimulation to activate spinal locomotor networks and posterior root stimulation to activate leg flexor and extensor motor pools during swing and stance phases, respectively. This technology effectively restores walking in post-stroke individuals while forward propulsion in the stance phase and foot dorsiflexion in the swing phase are insufficient. In this study the effectiveness of regulating the stance and swing phases while healthy volunteers walked on a treadmill with transcutaneous electrical stimulation of the posterior roots, leg muscles, and their combined effects has been examined. (2) Methods: We analyzed the kinematic characteristics of stepping movements in healthy participants with spinal stimulation of the posterior roots and flexor/extensor leg muscles. (3) Results: Our findings clearly show that posterior root stimulation at T12 combined with tibialis anterior muscle stimulation during the swing phase effectively regulates foot dorsiflexion, whereas posterior root stimulation at L2 combined with hamstrings and medial gastrocnemius stimulation during the stance phase effectively regulates forward propulsion. (4) Conclusions: Combined stimulation in the stance and swing phases within the same gait cycle resulted in the most coordinated stepping, and effective control of forward propulsion and foot dorsiflexion. Full article

Background and Objectives: Early assessment interventions are recommended for older adults with sarcopenia. Gait speed in older adults considerably decreases activities of daily living (ADL). However, the association between ADL and gait speed in older adults with sarcopenia has not yet been fully elucidated. This study aimed to clarify the association between walking speed and ADL in older adults with sarcopenia. Materials and Methods: A total of 72 older adults with sarcopenia who required support or care under Japan’s long-term care insurance system were included. Correlation and multivariate analyses were performed to examine the association between walking speed and ADL performance. A receiver operating characteristic analysis was used to evaluate the discrimination power of gait speed for ADL independence. Results: Gait speed was significantly and positively correlated with the Barthel Index scores for the men and women. ADL were independently and significantly associated with walking speed in the multivariate analysis. The threshold for gait speed that distinguished ADL independence in older adults with sarcopenia was 0.76 m/s (area under the curve = 0.75, sensitivity 72.7%, specificity 74.0%). Conclusions: Decreased gait speed in older adults with sarcopenia was associated with decreased ADL. Gait speed had high discriminatory power in identifying ADL independence. This indicates that an assessment intervention for gait speed in older adults with sarcopenia may have high clinical utility. Full article

Background: Static coronal alignment is considered a key of lower limb biomechanics after total knee replacement (TKR); however, its relationship with dynamic foot loading patterns and gait characteristics remains unclear. The primary objective of this prospective study was to investigate whether there is a correlation between dynamic plantar pressures and spatiotemporal parameters of gait and the coronal alignment of the lower limb after unilateral TKR for primary knee osteoarthritis (KOA). Methods: Thirty-two consecutive patients scheduled for TKR were evaluated preoperatively and at six months postoperatively. Changes in plantar pressure distribution and spatiotemporal gait parameters were collected using a multiplatform plantar pressure analysis system (PPAS), while coronal alignment was assessed using the femorotibial angle (FTA). Relationships with preoperative, postoperative, and correction-related alignment measures were examined using non-parametric statistical methods. Results: Dynamic plantar pressures and spatiotemporal gait parameters were not found to be consistently associated with pre- or postoperative values of FTA, respectively. Furthermore, the degree of correction did not appear to influence baropodometric outcomes. Conclusions: Static coronal alignment, as defined by the FTA, was not found to be consistently associated with dynamic plantar pressure patterns or spatiotemporal gait parameters at six months following unilateral TKR in our study population. These findings highlight the potential limitations of using solely static radiographic markers to evaluate complex functional outcomes such as gait. Full article

Background/Objectives: Falls are a leading cause of morbidity and mortality in older adults, even among those who are physically active. This study examined the associations between skeletal muscle mass, muscle strength, and muscle power and fall risk in physically active, community-dwelling older adults. Methods: A cross-sectional analysis was conducted with 280 participants (71.9 ± 5.3 years; 75% women) enrolled in the Stay Up–Falls Prevention Project. Assessments included skeletal muscle mass (anthropometric prediction equation), handgrip strength, lower limb strength and power (Five Times Sit-to-Stand test, 5×STS), and fall history over the past 12 months. Muscle power was calculated from 5×STS performance using the equation proposed by Alcazar and colleagues. Logistic regression models and receiver operating characteristic (ROC) curve analyses were performed. Results: Overall, 26.4% of participants reported at least one fall in the previous year, with a higher prevalence among women (28.9%) than men (18.8%). Fallers showed significantly lower handgrip strength (23.1 vs. 25.4 kg, p = 0.022) and poorer lower limb strength (9.2 vs. 8.7 s, p = 0.007) compared with non-fallers. However, no significant differences were found for skeletal muscle mass or sit-to-stand–derived power. In multivariable models adjusted for age, sex, body mass index, comorbidities, and medications, lower limb strength remained the only independent variable associated with fall status (OR = 1.78, 95% CI: 1.11–2.85, p = 0.016). ROC analysis confirmed fair discriminative capacity for 5×STS performance (AUC = 0.616, p = 0.003), with an optimal cut-off of 8.62 s (sensitivity = 78.4%, specificity = 33.0%). Handgrip strength, muscle mass, and power did not show independent associations with fall status. Conclusions: These findings indicate that the 5×STS test provides a simple, cost-effective, and functional indicator for fall-risk stratification in physically active older adults. Clinicians should consider the 5×STS as a sensitive functional indicator that contributes to fall risk stratification, ideally combined with complementary assessments (e.g., balance, gait, cognition) to improve risk stratification and guide preventive interventions in ageing populations. Full article

To address the complex surface curvature, massive dimensions, and variable pitch angles of wind turbine blades, this paper proposes a climbing robot design based on a variable-cell mechanism. By dynamically adjusting the support span and body posture, the robot adapts to the geometric features of different blade regions, enabling stable and efficient non-destructive inspection operations. Two reconfigurable configurations—a planar quadrilateral and a regular hexagon—are proposed based on the geometric characteristics of different blade regions. The configuration switching conditions and multi-leg cooperative control mechanisms are investigated. Through static stability margin analysis, the stable gait space and maximum stride length for each configuration are determined, optimizing the robot’s motion performance on surfaces with varying curvature. Simulation and experimental results demonstrate that the proposed multi-configuration gait planning strategy exhibits excellent adaptability and climbing stability across segments of varying curvature. This provides a theoretical foundation and methodological support for the engineering application of robots in wind turbine blade maintenance. Full article

With an aging population and the high incidence of neurological diseases, rehabilitative lower limb exoskeleton robots, as a wearable assistance device, present important application prospects in gait training and human function recovery. As the core of human–computer interaction, control strategy directly determines the exoskeleton’s ability to perceive and respond to human movement intentions. This paper focuses on the control strategies of rehabilitative lower limb exoskeleton robots. Based on the typical hierarchical control architecture of “perception–decision–execution,” it systematically reviews recent research progress centered around four typical control tasks: trajectory reproduction, motion following, Assist-As-Needed (AAN), and motion intention prediction. It emphasizes analyzing the core mechanisms, applicable scenarios, and technical characteristics of different control strategies. Furthermore, from the perspectives of drive system and control coupling, multi-source perception, and the universality and individual adaptability of control algorithms, it summarizes the key challenges and common technical constraints currently faced by control strategies. This article innovatively separates the end-effector control strategy from the hardware implementation to provide support for a universal control framework for exoskeletons. Full article

Background: Juvenile Idiopathic Arthritis (JIA) is a chronic inflammatory condition that can disrupt joint function and biomechanics, often leading to altered gait patterns. When coexisting with secondary scoliosis—a common musculoskeletal complication in children with JIA—postural and movement impairments may be further exacerbated. However, limited research has investigated the combined impact of JIA and secondary scoliosis on gait characteristics. This study aimed to evaluate gait parameters in children diagnosed with JIA and secondary scoliosis and to compare them with age-matched healthy peers. Methods: A total of 50 children (25 with JIA and secondary scoliosis, 25 healthy controls) were included. Demographic data, plantar pressure distribution, temporal gait parameters, and center of mass (CoM) displacement were assessed using computerized gait analysis. Group comparisons were performed using appropriate statistical methods. Results: Children with JIA and secondary scoliosis exhibited significantly lower forefoot loading on both dominant and non-dominant sides compared to controls (p < 0.05). Maximum loading values were also reduced bilaterally in the JIA group (p < 0.001). The dominant side single-limb support duration was significantly shorter (p = 0.027), and CoM displacement was greater (p = 0.044) in the JIA group. No differences were observed in rearfoot loading or walking speed. Conclusions: Children with coexisting JIA and secondary scoliosis demonstrate altered gait mechanics, likely reflecting compensatory adaptations due to joint inflammation and postural asymmetries. Gait analysis may offer valuable insights for tailoring rehabilitation strategies in this patient population. Full article

The gecko-inspired crawling robot driven by water hydraulic artificial muscles (WHAMs) incorporates the stable structural characteristics of geckos, making it particularly suitable for operation in aquatic environments. Conventional crawling robots typically employ electric or oil hydraulic actuation systems, which require complex sealing and waterproof designs when working in water. This study presented a bionic quadruped robot actuated by WHAMs that fundamentally circumvents waterproofing challenges. Although the joint module can dynamically adjust its output torque according to requirements, there has been a lack of theoretical basis for load adjustment. This research established the relationship between the leg joint load and the WHAM pressure difference, resulting in a pressure difference–load model for the leg joint. Through gait planning analysis, the maximum supporting force during robot motion was determined. Experimental tests on a single-leg prototype demonstrated a maximum static load capacity of 23 kg under stationary conditions, while during cycloidal motion the dynamic load capacity reached 10 kg. Both values satisfied the supporting force requirements of the planned gait. Furthermore, the pressure difference–load model showed good agreement with experimental results, providing theoretical guidance for load adjustment in leg joints. Full article

Intelligent lower-limb exoskeleton rehabilitation robots are increasingly superseding traditional rehabilitation equipment, making them a focus of research in this field. However, existing systems remain challenged by dynamic instability resulting from various disturbances during actual walking. To address this limitation, this study proposes a novel dynamic stability criterion. Through an analysis of the principles and limitations of the traditional zero-moment point (ZMP) stability criterion, particularly during the late single-leg support phase, a new stability criterion is introduced, which is founded on the swing projection polygon during single-leg support. This approach elucidates the variation patterns of the stability polygon during a single-step motion and facilitates a qualitative analysis of the stability characteristics of the human–robot system in multiple postures. To further enhance the stability and smoothness of gait trajectories in lower-limb exoskeleton rehabilitation robots, the shortcomings of conventional gait planning approaches, namely their non-intuitive nature and discontinuity, are addressed. A recurrent gait planning method leveraging Long Short-Term Memory (LSTM) neural networks is proposed. The integration of the periodic motion characteristics of human gait serves to validate the feasibility and correctness of the proposed method. Finally, based on the recurrent gait planning method, the dynamic stability of walking postures is verified through theoretical analysis and experimental comparisons, accompanied by an in-depth analysis of key factors influencing dynamic stability. Full article

In modern industrial environments, camera-based monitoring is essential for workflow optimization, safety, and process control, yet it raises significant privacy concerns when people are recorded. Realistic full-body anonymization offers a potential solution by obscuring visual identity while preserving information needed for automated analysis. Whether such methods also conceal biometric traits from human pose and gait remains uncertain, although these biomarkers enable person identification without appearance cues. This study investigates the impact of full-body anonymization on gait-related identity recognition using DeepPrivacy2 and a custom CCTV-like industrial dataset comprising original and anonymized sequences. This study provides the first systematic evaluation of whether pose-preserving anonymization disrupts identity-relevant gait characteristics. The analysis quantifies keypoint shifts introduced by anonymization, examines their influence on downstream gait-based person identification, and tests cross-domain linkability between original and anonymized recordings. Identification accuracy, domain transfer between data types, and distortions in derived pose keypoints are measured to assess anonymization effects while retaining operational utility. Findings show that anonymization removes appearance but leaves gait identity largely intact, indicating that pose-driven anonymization is insufficient for privacy protection. Effective privacy requires anonymization strategies that explicitly target gait characteristics or incorporate domain-adaptation mechanisms. Full article

Background and Objectives: Sarcopenia and muscle wasting contribute significantly to functional decline in older adults, but differences in lower extremity muscle stiffness and gait variability between these groups are not yet fully understood. This study aimed to compare gait variability, and lower extremity muscle stiffness during contraction and relaxation in community-dwelling older adults classified as non-diseased, sarcopenic, and dynapenic. Materials and Methods: This cross-sectional study included 164 community-dwelling older adults classified as non-diseased, dynapenic, or sarcopenic, based on handgrip strength, 5-time sit-to-stand test, and skeletal muscle index. Spatiotemporal gait variability was measured at the participants’ preferred speed. Moreover, muscle thickness, as well as the contractile and relaxed stiffness, were measured for the rectus femoris (RF), biceps femoris (BF), tibialis anterior (TA), gastrocnemius medialis (GAmed), and lateralis (GAlat). Results: In dynapenic and sarcopenic groups, gait variability increased across most parameters, but only the step width coefficient of variation differed significantly between the dynapenic and sarcopenic groups. Contractile stiffness of the RF, BF, and GAlat was lower in both groups, with additional GAmed stiffness reduction in the sarcopenic group. Relaxed stiffness of the BF and GAmed was significantly higher in the sarcopenic group than in the dynapenic group. Conclusions: This study identified differences in muscle thickness, stiffness, and gait variability among non-diseased, dynapenic, and sarcopenic older adults. Step width variability, GAmed contractile stiffness, and BF and GAmed relaxed stiffness emerged as potential early indicators for distinguishing dynapenia from sarcopenia. These findings highlight the importance of assessing muscle quality—including both mass and stiffness characteristics—to better characterize early stages of age-related muscle decline and to inform targeted intervention strategies. Full article

Objective: This study aimed to systematically evaluate the therapeutic effects of repetitive transcranial magnetic stimulation (rTMS) on gait, motor function, and balance in patients with Parkinson’s disease (PD) and identify optimal stimulation parameters for clinical application. Methods: This systematic review and meta-analysis of randomized controlled trials (CTs) was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, EMBASE, Cochrane Central, Scopus, and Ovid-LWW were searched until December 2024 for RCTs evaluating the effects of rTMS on PD-related gait, balance, or motor outcomes. Nineteen studies (n = 547) met the inclusion criteria. Data on study characteristics, rTMS protocols (frequency, target area, pulses, session duration, number of sessions, and treatment duration), and outcome measures (freezing of gait questionnaire [FOG-Q], gait speed, Unified Parkinson’s Disease Rating Scale Part III [UPDRS-III], UPDRS total, and timed up and go [TUG] test) were extracted. Effect sizes (Hedges’ g) were pooled using inverse variance meta-analysis, heterogeneity was assessed using I², and publication bias was assessed using funnel plots and Egger’s regression. Results: rTMS produced significant improvements in gait freezing (FOG-Q: g = −0.74; 95% confidence interval [CI] [−1.05, −0.43]; p < 0.001), gait speed (g = 0.62; 95% CI [0.29, 0.95]; p < 0.001), and motor symptoms (UPDRS-III: g = −0.42; 95% CI [−0.70, −0.15]; p = 0.003). No significant effects were observed for UPDRS total (g = 0.18; p = 0.58) or balance (TUG, g = −0.29; p = 0.06). Egger’s test indicated publication bias for gait speed (p = 0.016); however, trim-and-fill imputed zero studies. Subgroup analyses indicated that high-frequency stimulation of the supplementary motor area (SMA) for ≥20 min over 10 sessions (total duration <2 weeks or ≥2 weeks) optimally improved gait speed, whereas low-frequency stimulation targeting M1 and SMA with >1000 pulses per session for 20 min over 10 sessions within <2 weeks most effectively improved the UPDRS-III scores. Conclusions: rTMS exerts moderate and significant benefits on gait and motor performance in PD, particularly when tailored protocols involving SMA or M1 stimulation are employed. High-frequency SMA protocols improve gait speed, whereas low-frequency M1/SMA protocols optimize motor symptom relief. These findings provide evidence-based guidance for rTMS implementation in PD rehabilitation. Full article

Background and Clinical Significance: Hemiplegia following a cerebrovascular accident (CVA) disrupts gait symmetry and efficiency, compromising functional independence. The integration of surface electromyography (sEMG) and inertial measurement units (IMU) enables quantitative assessment of muscle activation and segmental dynamics, providing objective data for therapeutic planning. Case presentation: A 57-year-old male with chronic right hemiplegia, eight years post-ischemic stroke of the left middle cerebral artery. The patient ambulated independently without assistive devices, exhibiting right lower-limb circumduction. Clinical assessment revealed the following scores: Barthel Index 85/100, Tinetti Performance-Oriented Mobility Assessment (POMA) 16/28, Timed Up and Go (TUG) test 13 s, and Modified Ashworth Scale (MAS) scores of 1 (upper limb) and 1+ (lower limb). Methods: Multichannel sEMG (Miotool 800^®, 8 channels) was recorded form the lumbar erectors, gluteus medius and maximus, vastus medialis, vastus intermedius, vastus lateralis, biceps femoris, tibialis anterior, medial gastrocnemius, and lateral gastrocnemius. Ag/AgCI electrodes were positioned according to SENIAM recommendations: sampling rate: 1000 Hz; band-pass filter: 20–500 Hz; notch filter: 60 Hz; normalization to %MVC. Simultaneously, IMU signals (Xsens DOT^®, 60 Hz) were collected from both ankles during slow, medium and fast walking (20 s each) and compared with a healthy control subject. Results: The patient exhibited reduced sEMG amplitude and increased peak irregularity on the affected side, particularly in the gluteus medius, tibialis anterior, and gastrocnemius, along with agonist desynchronication. IMU data revealed decreased range of motion and angular pattern irregularity, with inconsistent acceleration peaks in the right ankle compared to the control, confirming neuromuscular and kinematic asymmetry. Conclusions: The combined sEMG-IMU analysis identified deficits in selective motor control and propulsion on the affected hemibody, providing essential information to guide physiotherapeutic interventions targeting pelvic stability, dorsiflexion, and propulsive phase training, enabling objective follow-up beyond specialized laboratory settings. Full article

Background: This study explored the potential of a passive exoskeleton (Exo) to improve cadence, step length, oxygen uptake, and reduce metabolic power in senior adults, with the expectation that slow walkers (SW < 0.56 m/s) would benefit more than intermediate walkers (IW ≥ 0.56 m/s). Methods: Twenty-three senior adults walked on a treadmill at their self-selected speed using the Exo, noExo, and a placebo (Sham) in a randomized and balanced order. A lower back inertial measurement unit, a heart rate monitor, and an oxygen uptake system were used to monitor spatiotemporal and cardiopulmonary parameters. Cadence, step length, heart rate, oxygen uptake (VO₂ and relative VO₂), metabolic power, and respiratory exchange ratio were extracted. A two-way MANOVA was performed across Exo vs. noExo vs. Sham and SW vs. IW. Results: Using Exo did not show any significant changes in spatiotemporal or cardiopulmonary outcomes compared to the conditions for both SW and IW. IW vs. SW seniors had significantly higher cadence (15–19%), step length (31–41%), relative VO₂ (21–23%), and metabolic power (21–23%) in all devices (p < 0.05). Conclusions: These findings show that the use of Exo among senior adults does not improve spatiotemporal parameters nor reduce metabolic powers even among SW. Full article

Background: Helsmoortel-Van der Aa syndrome (HVDAS) is a rare multisystemic neurodevelopmental disorder caused by pathogenic variants in the Activity-Dependent Neuroprotective Homeobox Protein (ADNP) gene. Since the extensive clinical description of a cohort of 78 affected individuals in 2019, numerous reports described additional cases affected by the condition. However, no systematic synthesis of the clinical and molecular spectrum of these additional individuals has been conducted to date. Methods: In accordance with the PRISMA 2020 guidelines, we performed a systematic review of all publications describing individuals with genetically confirmed HVDAS. Clinical characteristics, comorbidities, and developmental milestones were systematically extracted to illustrate novel or underrecognized manifestations. Results: A total of 105 individuals reported across 34 publications were included. Of these, 66 were clinically and genetically evaluated, and 39 were analyzed only at the genetic level. Our analysis refines the phenotypic spectrum of HVDAS, including developmental delay, visual anomalies, and congenital heart defects. The additional literature also allows us to characterize in more detail the ophthalmological abnormalities, gait disturbances, and the cognitive profile of HVDAS. Advances in ADNP methylation profiling further enhance diagnostic precision and variant interpretation in this evolving neurodevelopmental syndrome. Conclusions: This systematic review provides a comprehensive synthesis of the clinical, genetic, and epigenetic landscape of HVDAS. It underscores the multisystemic nature of the disorder and the need for multidisciplinary management. The expanding phenotypic heterogeneity likely reflects both improved clinical recognition of the more subtle features and the tendency to prioritize publication of more complex or severely affected cases. Full article