Search Results (260)

A 70-year-old Japanese woman with longstanding hearing loss and asthma developed floating sensations, left finger numbness, and postural instability one day after influenza vaccination, leading to hospital admission. Neurological examinations showed hearing loss, hyperreflexia, left-predominant ataxia, bilateral mild bathyanesthesia, and inability to tandem gait. Cerebrospinal fluid (CSF) analysis showed no pleocytosis or malignant cells, but revealed positive oligoclonal bands and elevated myelin basic protein. Despite no contrast agent use due to asthma, brain magnetic resonance imaging (MRI) revealed pontine hyperintensities on diffusion-weighted imaging (DWI) and T2-fluid attenuated inversion recovery (T2-FLAIR) sequences, along with hyperperfusion on arterial spin labeling (ASL) imaging. Serum anti-aquaporin-4 antibodies (AQP4-Ab) were negative by ELISA. Given the temporal proximity to vaccination and elevated demyelination markers, brainstem-type acute disseminated encephalomyelitis (ADEM) was initially suspected. Symptoms nearly resolved after two cycles of methylprednisolone pulse therapy. Notably, hyperperfusion gradually improved on ASL imaging. Post-discharge, a cell-based assay confirmed the diagnosis of neuromyelitis optica spectrum disorder (NMOSD) by detecting positive anti-AQP4-Ab. She has been relapse-free for about a year without any immunosuppressants or biologics. Although contrast-enhanced MRI remains the gold standard modality for lesion evaluation due to its high sensitivity, hyperperfusion on ASL may provide a useful alternative in patients for whom contrast agents are contraindicated, such as those with asthma or impaired renal function. Full article

(1) Background: Chronic ankle instability (CAI), a common outcome of ankle sprains, involves recurrent sprains, balance deficits, and gait impairments linked to both peripheral and central neuromuscular dysfunction. Dual-task (DT) demands further aggravate postural control, especially during stair descent, a major source of fall-related injuries. Yet the biomechanical mechanisms of stair-to-ground transition in CAI under dual-task conditions remain poorly understood. (2) Methods: Sixty individuals with CAI and age- and sex-matched controls performed stair-to-ground transitions under single- and dual-task conditions. Spatiotemporal gait parameters, center of pressure (COP) metrics, ankle inversion angle, and relative joint work contributions (Ankle%, Knee%, Hip%) were obtained using 3D motion capture, a force plate, and musculoskeletal modeling. Correlation and regression analyses assessed the relationships between ankle contributions, postural stability, and proximal joint compensations. (3) Results: Compared with the controls, the CAI group demonstrated marked control deficits during the single task (ST), characterized by reduced gait speed, increased step width, elevated mediolateral COP root mean square (COP-ml RMS), and abnormal ankle inversion and joint kinematics; these impairments were exacerbated under DT conditions. Individuals with CAI exhibited a significantly reduced ankle plantarflexion moment and energy contribution (Ankle%), accompanied by compensatory increases in knee and hip contributions. Regression analyses indicated that Ankle% significantly predicted COP-ml RMS and gait speed (GS), highlighting the pivotal role of ankle function in maintaining dynamic stability. Furthermore, CAI participants adopted a “posture-first” strategy under DT, with concurrent deterioration in gait and cognitive performance, reflecting strong reliance on attentional resources. (4) Conclusions: CAI involves global control deficits, including distal insufficiency, proximal compensation, and an inefficient energy distribution, which intensify under dual-task conditions. As the ankle is central to lower-limb kinetics, its dysfunction induces widespread instability. Rehabilitation should therefore target coordinated lower-limb training and progressive dual-task integration to improve motor control and dynamic stability. Full article

Background/Objectives: Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by motor symptoms such as tremor, bradykinesia, rigidity, and postural instability. In the absence of disease-modifying therapies, exercise remains one of the few interventions shown to effectively reduce fall risk and improve mobility. However, it remains unclear whether skeletal muscle ATP metabolism is impaired in PD, and whether the benefits of exercise arise primarily from improvements in central motor control or peripheral metabolic adaptations. Methods: Fourteen individuals with PD and five healthy controls underwent kinetic ³¹P Magnetic Resonance Spectroscopy (MRS) to assess resting muscle ATP synthesis and dynamic ³¹P MRS during in-magnet exercise to evaluate oxidative phosphorylation in active muscle. Results: At rest, ATP synthesis rates mediated by ATPase and creatine kinase (CK) were on average 46 ± 23% and 24 ± 9% lower, respectively, in the PD group compared to controls (p < 0.005), suggesting peripheral mitochondrial dysfunction. During plantar flexion exercise at 15% of lean body mass, range of motion (ROM) was reduced by 22 ± 5% in PD participants (p = 0.01). Despite this, post-exercise recovery of phosphocreatine (PCr) and inorganic phosphate (Pi) was similar between groups. Recovery time constants for PCr and Pi correlated with participants’ total weekly exercise time, indicating a metabolic adaptation to regular physical activity. Modest ROM improvements were observed in both groups following calf-raise exercise training. Conclusions: Reduced skeletal muscle ATP metabolism may contribute to peripheral weakness in PD. Regular exercise appears to promote adaptive metabolic responses, highlighting the need for therapeutic strategies targeting both central and peripheral components of PD. Full article

Knee osteoarthritis (OA) is a prevalent condition in older adults that often results in impaired gait and balance, increased risk of falls, and reduced quality of life. Conventional clinical assessments may not adequately capture these deficiencies. This study investigated the gait and balance of elderly individuals with knee OA using wearable inertial measurement units (IMUs). Forty-four participants with Kellgren–Lawrence grade 2–3 knee OA (71.23 ± 5.75 years) and forty-five age-matched controls (70.87 ± 4.30 years) completed dynamic balance (balance board), static balance (single-leg stance), ‘timed up and go’ (TUG), and normal walking tasks. Between 2 and 8 IMUs, depending on the task, were placed on the head, chest, waist, knees, ankles, soles, and balance board to record kinematic data. Balance was quantified using absolute angular velocity and linear acceleration, with group differences analyzed by MANOVA and Bonferroni-adjusted univariate tests. The participants with knee OA exhibited greater gait asymmetry, although the difference was not significant. However, they consistently demonstrated higher absolute angular velocities than controls across most body segments during static and dynamic tasks, indicating reduced postural stability. No group differences were observed in TUG performance. These findings suggest that IMU-based measures, particularly angular velocity, are sensitive to balance impairment detection in knee OA. Incorporating IMU technology into clinical assessments may facilitate early identification of instability and guide targeted interventions to reduce fall risk. Full article

A 10-month-old Poodle was presented with intermittent non-weight-bearing lameness of the left thoracic limb. Orthopedic and radiographic examinations revealed medial shoulder luxation and markedly reduced elbow extension. A two-stage surgical approach was performed. In the first stage, selective myotomy of periarticular structures, including the biceps brachii–brachialis complex and the extensor carpi radialis muscle, was conducted via medial and lateral approaches. A trans-articular external skeletal fixator was applied to maintain elbow extension. Elbow extension improved from 105° preoperatively to 142°. After confirming functional recovery of the elbow joint, the second stage involved shoulder arthrodesis using a circular osteotomy technique with a radial saw, which enabled fine-tuned intraoperative adjustment of limb alignment based on the contralateral limb posture. At nine months postoperatively, the patient exhibited a symmetrical gait, full weight-bearing, and no evidence of discomfort on range of motion assessment. This case highlights the clinical relevance of secondary elbow contracture associated with congenital shoulder instability and suggests that a combination of targeted muscle release and adjustable arthrodesis may offer favorable outcomes in managing complex joint dysfunction. Full article

Background/Objectives: This study investigated postural stability in male inmates of a semi-open correctional facility, with a specific focus on comparing individuals with and without a history of substance dependence. The aim was to identify how addiction-related neurophysiological changes impact postural control under varying sensory and biomechanical demands. Methods: A total of 47 adult male prisoners (mean age: 24.3 years) participated in this study. Nineteen inmates had a documented history of alcohol or drug dependence (addicted group), while twenty-eight had no such history (non-addicted group). All participants were physically able and free of neurological disorders. Postural control was assessed using a stabilometric platform and wireless IMU across six 30 s standing tasks of varying difficulty (bipedal/unipedal stance and eyes open/closed). Linear (center of pressure path and ellipse area) and nonlinear (sample entropy, fractal dimension, and the Lyapunov exponent) sway metrics were analyzed, along with trunk kinematics from IMU data. This study received institutional ethical approval; trial registration was not required. Results: The addicted group showed greater instability, especially in the eyes-closed and single-leg tasks, with increased sway and irregularity in the anterior–posterior direction. IMU data indicated altered trunk motion, suggesting impaired neuromuscular control. In contrast, non-addicted individuals demonstrated more efficient, targeted postural strategies, while addicted participants relied on broader, less selective movements, possibly reflecting compensatory or neuroadaptive changes from substance use. Conclusions: Substance dependence is associated with compromised postural stability in incarcerated men. Balance assessments may be valuable for detecting functional impairments and guiding rehabilitation within prison healthcare systems. Full article

This study used stair-embedded force plates to investigate the effects of lower-limb muscle fatigue on dynamic postural control during stair descent in young adults. Twenty-five healthy male adults (age = 19.2 ± 1.5 years) were tested for stair descent gait in pre-fatigue and post-fatigue conditions. To induce fatigue, participants performed a sit-to-stand task. The kinematic and kinetic data were collected synchronously, and gait parameters were analyzed. Data were analyzed using one-dimensional statistical parametric mapping (SPM1d) and paired t-tests in SPSS. After fatigue, the right knee flexion angle increased significantly across all phases (0–14%, p < 0.001; 14–19%, p = 0.032; 42–50%, p = 0.023; 60–65%, p = 0.022; 80–100%, p = 0.012). Additionally, the step width widened notably (p < 0.001), while the proportion of the swing phase decreased (p = 0.030). During the event of right-foot release, the left knee flexion (p = 0.005) and ankle dorsiflexion (p = 0.001) angle increased significantly, along with a larger left ankle plantarflexion moment (p = 0.032). After fatigue, the margin of stability in the anterior–posterior direction (MoS-AP) (p = 0.002, p = 0.014) and required coefficient of friction (RCOF) (p = 0.031, p = 0.021) significantly increased at the left-foot release and right-foot release moments. This study demonstrates that lower-limb muscle fatigue increases dynamic instability during stair descent. Participants adopted compensatory strategies, including widening step width, reducing single-support duration, and enhancing ankle plantarflexion to offset knee strength deficits. These adaptations likely reflect central nervous system mechanisms prioritizing stability, highlighting the ankle’s compensatory role as a potential target for joint-specific interventions in fall prevention and rehabilitation. Future studies should investigate diverse populations, varying fatigue levels, and comprehensive neuromuscular indicators. Full article

With the development of technology, comfort has gradually developed into the main criterion for evaluating intelligent vehicle performances. In this study, a field test was carried out under five common driving conditions, and 60 participants took part. Passenger posture data, vehicle motion data and passenger subjective comfort data were collected. A paired sample T-test and a ridge regression algorithm were used to explore the relationship between passenger posture swing parameters and subjective comfort. The results show that under the same driving conditions, the speed of posture swing was significantly higher for passengers who experienced discomfort. Furthermore, we found that the change in angular velocity was the main cause of passenger discomfort under different driving conditions. This suggested that the design of intelligent vehicle algorithms should focus on the angular velocity variation among passengers. Finally, based on traditional machine learning algorithms and deep learning algorithms, this paper establishes two models for predicting comfort through passenger posture instability. The accuracy of the machine learning model in predicting passenger comfort was 87.1%, while that for the deep learning model was 89%. The findings are useful in providing a theoretical basis for improving the comfort of intelligent vehicles. Full article

Background/Objectives: Individuals with Parkinson’s disease (PD) often experience four major motor symptoms—tremor, rigidity, bradykinesia, and postural instability/gait disorder. Although these symptoms have been shown to affect activities of daily living, their impact on the level of at-home physical activity (PA) in this population remains unexplored. We aimed to investigate the relationship between the four major motor symptoms of PD and at-home PA in these individuals. Methods: This retrospective cross-sectional study included 17 individuals with PD. We examined the relationship between the Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale Part 3 score and the time spent in three PA intensities (sedentary behavior, light PA [LPA], and moderate-to-vigorous PA) within the home. Pearson’s correlation coefficient was used for statistical analysis. Results: In the initial step analysis, a significant negative correlation was observed between the overall motor symptom score and the time spent in LPA inside the home (r_s [95% confidence interval]: −0.72 [−0.93 to −0.25]; p < 0.01). In the second step analysis, a significant negative correlation was observed between the bradykinesia score and the time spent in LPA inside the home (r_s: −0.74 [−0.92 to −0.30]; p < 0.01). Conclusions: Among the four major motor symptoms, only the severity of bradykinesia influenced the time spent in LPA inside the home. Thus, rehabilitation treatment focusing on bradykinesia may be beneficial for increasing the time spent in LPA inside the home for individuals with PD. Full article

Background/Objectives: Despite a substantial duration of recovery following the modified Broström procedure (MBP), many individuals do not entirely recover their preinjury sports performance. Return to sports (RTS) can be affected by multiple elements apart from a patient’s motivation. This study aimed to investigate the factors influencing RTS after anatomical ligament repair for chronic ankle instability. Methods: Sixty-two patients aged under 35 who underwent the MBP were regularly monitored for up to 3 years. Of these, 51 patients (82.3%) returned to their preinjury level of sports activity (return group), while 11 patients (17.7%) complained of partial or significant limitations (non-return group). Clinical outcomes were measured by the Foot and Ankle Outcome Score (FAOS) and the Foot and Ankle Ability Measure (FAAM). Mechanical stability was examined through physical examination and stress radiography. Peroneal strength was evaluated with an isokinetic dynamometer. Static and dynamic postural control abilities were tested using Biodex posturography. Results: Significant group differences were found in FAOS pain (94.7 points in the return group vs. 85.1 points in the non-return group; p = 0.004) and sports (91.2 vs. 78.8 points; p < 0.001) subscales. In the FAAM, the sports activity subscale also showed significant disparities (90.5 vs. 77.4 points, p < 0.001). Mechanical instability recurred in 2 patients (3.9%) in the return group and 4 patients (36.4%) in the non-return group, indicating a significant difference (p < 0.001). No notable differences were identified in stress radiography values or peroneal strength measurements. Posturographic evaluation showed that static postural control ability (overall stability index) did not differ significantly between the groups (1.22 in the return group vs. 1.43 in the non-return group); however, dynamic postural control ability differed substantially (1.41 vs. 2.33, p = 0.002). Conclusions: Residual pain, recurrence of mechanical instability, and insufficient recovery of dynamic postural control ability were associated with the return to preinjury level of sports activity after the MBP. Comprehensive rehabilitation protocols should address these factors to facilitate optimal postoperative sports participation. Full article

Parkinson’s disease (PD) is a common neurodegenerative disorder caused by progressive loss of dopaminergic neurons in the substantia nigra and the presence of Lewy bodies. While PD is most recognized by its motor symptoms (resting tremor, rigidity, bradykinesia, and postural instability), cognitive decline (CD) may become apparent as PD progresses, leading to Parkinson’s disease dementia (PDD). Type 2 diabetes mellitus (T2DM) and insulin resistance (IR) are risk factors for dementia, especially Alzheimer’s disease; however, their influence on dementia in PD is underexplored. Therefore, we sought to determine the effect of T2DM and IR on dementia in PD. A systematic search of articles from 2005 to March 2025 was undertaken using Embase, PubMed, Scopus, Web of Science, and citation searching. Case–control, cross-sectional, longitudinal, and non-human population studies assessing cognitive outcomes in individuals with PD, with and without T2DM and IR, were included (PROSPERO registration number CRD420251013367). In total, 27 studies met the inclusion criteria, with clinical sample sizes ranging from 23 to 544,162 participants. Among the 23 clinical studies, 15 identified T2DM as a contributor to cognitive decline (CD) in PD, and 4 specifically examined insulin resistance (IR). Elevated HbA1c was consistently associated with poorer cognitive performance and increased risk of Parkinson’s disease dementia (PDD); HbA1c ≥ 7% independently predicted cognitive impairment (OR = 4.25, 95% CI: 1.59–11.34). Vascular and inflammatory markers, including elevated LDL-C, fibrinogen, and hs-CRP, further exacerbated CD. MoCA and MMSE scores were the most common cognitive measures, consistently showing worse outcomes in PD patients with T2DM. Preclinical studies supported these associations, showing that high-fat-diet-induced T2DM and IR aggravated dopaminergic neuronal loss by 38–45%, increased α-synuclein by 35%, and heightened microglial activation, providing mechanistic evidence for the observed clinical associations. This systematic review, the first to examine the impact of T2DM and IRs on the occurrence and advancement of CD in PD patients, demonstrates a possible association between the two. However, these results demonstrate the need for larger sample sizes and the inclusion of additional clinical variables, such as HbA1c levels and pharmacological interventions, providing further information about the link between metabolic dysfunction and CD in PD. To further strengthen this link, longitudinal studies with systematic follow-ups are essential to establish causal links and avoid misdiagnosis in clinical practice. Full article

Background: Stair ambulation is a complex motor task that presents a substantial fall risk for people with Parkinson’s disease (PwPD) who often have postural instability and gait difficulty (PIGD) and experience unpredictable freezing of gait (FOG) episodes. While dual-task (DT) interference during level walking is well-documented, its impact on stair ambulation, an everyday, high-risk activity, remains poorly understood. Objective: The aim of this study was to quantify the impact of dual tasking on patterns of motor control during stair ambulation using kinetic data from The Stair Ambulation and Functional Evaluation of Gait (Safe-Gait) system. Methods: Seventeen individuals with Parkinson’s disease (PD) completed three single-task (ST) and three dual-task (DT) trials on the Safe-Gait system, which sampled kinetic data via embedded force plates during stair ascent and descent. The force plate data were used to quantify step time, braking and propulsive impulses, and center of pressure (CoP) displacement and sway speed to assess DT effects on stair ambulation kinetics. Results: Dual-task conditions led to significant increases in step time (p < 0.001), braking impulse (p < 0.01), anteroposterior center of pressure (CoP) range (p < 0.05), and a decrease in mediolateral CoP speed (p < 0.01). Conclusions: Dual tasking during stair ambulation altered gait kinetics in PwPD, evidenced by slower, less stable movement patterns. These findings highlight the impact of cognitive motor DT interference on functional mobility and support the use of instrumented stair assessments to guide therapeutic care and fall risk interventions. Full article

This study aimed to compare muscle activation and neuromuscular symmetry during isometric squat exercises performed on stable and unstable surfaces. Nineteen recreationally active males (aged 18–27) participated in the experiment. A hard floor represented the stable surface, while the unstable conditions included a BOSU ball with the dome side up, a BOSU ball with the flat side up, and a gymnastics mat. Participants performed two 10 s sets of isometric squats on each surface using body weight. Electromyographic (EMG) activity was recorded from the vastus medialis (VM), vastus lateralis (VL), medial gastrocnemius (MG), and lateral gastrocnemius (LG). The central focus of this study was neuromuscular symmetry, which is defined in biomechanics as the balanced muscle activity between homologous and synergistic muscle groups. Since surface instability may influence muscle coordination and postural control, this study investigated whether muscle activation symmetry differs across varying surface conditions. The results showed no statistically significant differences in muscle activation across all surfaces for VM, VL, MG, and LG (p > 0.05). These findings indicate that surface stability does not significantly impact the activation or symmetry of these lower limb muscles during isometric squats. Therefore, different surfaces may be used interchangeably in training or rehabilitation programmes without altering muscle engagement. This flexibility could be advantageous for athletes, clinicians, or individuals aiming to diversify exercise modalities or adapt routines based on surface availability. Full article

Background: Persistent Postural-Perceptual Dizziness (PPPD) is a chronic vestibular disorder characterized by dizziness, instability, and visual hypersensitivity. Vestibular Physical Therapy (VPT) is commonly used, but its efficacy remains uncertain due to limited and heterogeneous evidence. Objective: This systematic review and meta-analysis aimed to evaluate the effectiveness of VPT in reducing dizziness and improving balance in individuals with PPPD. Methods: A systematic search of MEDLINE and PEDro was conducted in January 2025. Studies were selected following PRISMA guidelines and included if they assessed VPT interventions in patients diagnosed with PPPD. Risk of bias was assessed using the PEDro scale and the modified Newcastle–Ottawa Scale. The meta-analysis focused on pre- and post-intervention changes in Dizziness Handicap Inventory (DHI) scores using a random-effects model. Results: Six studies met the inclusion criteria. VPT significantly reduced DHI scores (pooled Hedges’ g = 1.60; 95% CI: 0.75–2.45), indicating a moderate to large improvement. Additional outcomes included improvements in postural control (e.g., mini-BESTest and posturography) and psychological well-being (anxiety and depression questionnaires). However, high heterogeneity (I² = 92%) was present across studies. Conclusions: VPT may improve dizziness and balance in PPPD, though evidence is limited. Further high-quality trials with standardized protocols are needed. Full article

Multiple Sclerosis (MS) is a chronic neurological disorder affecting the central nervous system that significantly impairs postural control and functional abilities. Robotic-assisted gait training mitigates this functional deterioration. This preliminary study aims to investigate the effects of a four-week gait training with the ExoAtlet II exoskeleton on static balance control and functional mobility in five individuals with MS (Expanded Disability Status Scale ≤ 2.5). Before and after the training, they were assessed in quiet standing under Eyes Open (EO) and Eyes Closed (EC) conditions and with the Timed Up and Go (TUG) test. Center of Pressure (CoP) Sway Area, Antero–Posterior (AP) and Medio–Lateral (ML) CoP displacement, Stay Time, and Total Instability Duration were computed. TUG test Total Duration, sit-to-stand, stand-to-sit, and linear walking phase duration were analyzed. To establish target reference values for rehabilitation advancement, the same evaluations were performed on a matched healthy cohort. After the training, an improvement in static balance with EO was observed towards HS values (reduced Sway Area, AP and ML CoP displacement, and Total Instability Duration and increased Stay Time). Enhancements under EC condition were less marked. TUG test performance improved, particularly in the stand-to-sit phase. These preliminary findings suggest functional benefits of exoskeleton gait training for individuals with MS. Full article