Restorative neurology and neuroscience最新文献

Reduced toe clearance during the swing phase of gait, often referred to as foot drop, is a common cause of walking disability in clinical populations like stroke, cerebral palsy, or multiple sclerosis. Individuals with foot drop often wear an ankle-foot orthosis (AFO) to prevent excessive plantarflexion, but many commercially available AFOs overly restrict ankle mobility or make the wearer feel unstable/uncomfortable. Soft AFOs-AFOs with soft attachment points and elastic assistance-are designed to retain ankle mobility and comfort. However, their effect on gait biomechanics, as compared to traditional AFOs, is not well understood. Therefore, the objective of the current study was to perform a comprehensive biomechanical and neurophysiological comparison of soft AFOs with traditional AFOs. Sagittal plane kinematics, ground reaction forces, and lower extremity muscle activation were measured in 23 neurologically intact individuals while walking on a treadmill without assistance from an AFO (No AFO) and then with unilateral assistance from four commercially available AFOs (rigid anterior, flexible posterior leaf spring, and two soft AFOs). We found that soft AFOs allowed for greater ankle dorsiflexion velocity, plantarflexion velocity, and plantarflexion angle while retaining or increasing dorsiflexion during the swing phase. We also found that the traditional AFOs reduced propulsive ground reaction forces compared to the soft AFOs, and the rigid anterior AFO reduced plantarflexor muscle activity compared to the soft AFOs. These results highlight the differences between different commercially available AFOs and present soft AFOs as an exciting alternative to traditional AFOs when ankle mobility is desired.

Kinematic assessments provide a quantitative evaluation of movement outcomes in chronic stroke survivors. However, it is unclear whether these assessments provide an added benefit to standardized clinical assessments when evaluating functional independence. We hypothesized that kinematic assessments of ipsilesional arm motor and cognitive performance would be better at predicting functional independence compared to their standardized clinical assessment counterparts. We recruited 21 chronic stroke survivors with severe hemiparesis to complete 2 clinical assessments (Jebsen-Taylor Hand Function Test, Grooved Pegboard Test) and 2 kinematic assessments on the Kinereach motion tracking system (a simple reaching task and a cognitively challenging reaching task). We found moderate-to-weak correlations between the Functional Independence Measure (FIM) and each of the kinematic outcomes. The clinical assessments had weak correlations with the FIM. Thus, kinematic assessments provided no significant advantage over clinical assessments in predicting functional independence.

BackgroundThe aim of study was to determine changes in the balance parameters after balance-coordination program in children with dyslexia.MethodsProspectively sixteen children with dyslexia were included. Balance parameters of dyslexic children were compared with healthy children. Dyslexic children were given balance coordination exercises three times a week for six weeks. The static and dynamic balance were tested with the Modified Clinical Test of Sensory Interaction on Balance (mCTSIB) and Limits of Stability (LOS) tests and Pediatric Quality of Life Inventory Scale (PedsQL) was used to assess quality of life.ResultsPostural sway velocities on the firm and foam surfaces with eyes opened and closed conditions of mCTSIB were found to be decreased and movement velocity, endpoint excursion, and maximum excursion in anterior and posterior directions of LOS, social, school and total scores of PedsQL increased in the dyslexia group after the treatment (p < 0,01).ConclusionThe children with dyslexia have distinct alterations on balance compared to their peers. These alterations, along with their quality of life, have shown to be greatly improved after a exercise program.

Gait impairments are a well-documented consequence of stroke, yet the impact of transient ischemic attack (TIA) on gait remains underexplored. This study aimed to characterize acute changes in gait patterns within three days of stroke or TIA onset using an accelerometer, and to examine the relationship between gait patterns and questionnaire-based measures of balance confidence. We found that patients with TIA showed significantly lower variability in swing time, stance time, and step time than patients with stroke. Comparisons between patients with TIA and controls indicated that controls had higher mean step velocity and lower step time asymmetry. Additionally, compared with controls, patients with stroke demonstrated a slower and less temporally consistent pace, indicated by shorter step length, lower step velocity, and higher standard deviation (SD) for swing time, stance time, and step time. They also showed greater variability, reflected by higher step length SD, and more pronounced gait asymmetry, with greater asymmetry in swing time, step time, and stance time. The balance confidence was associated with gait parameters in patients with stroke and in controls, but not in patients with TIA. In both groups, higher confidence related to longer step length and faster step velocity; in stroke it was also linked to lower swing time variability and longer step and stance times, and in controls to lower step time variability. These findings demonstrate that TIA involves detectable neurological changes affecting motor control, highlighting the value of detailed accelerometer-based gait analysis for early detection of functional deficits.

Driving after stroke requires complex coordination of cognitive and motor systems, yet the influence of post-stroke cognitive impairment on lower limb motor control during driving remains poorly understood. This pilot study examined the association between cognitive function and lower limb motor control of gas/brake pedal control in stroke survivors. We hypothesized that compromised cognitive function would be associated with worse gas and brake pedal control. Twenty stroke survivors (65.89 ± 9.67 years; 6 females) participated. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA) and Useful Field of View (UFOV) test scores for divided and selective attention. Participants performed a car-following task in a driving simulator requiring precise gas and brake control. Pedal control was quantified by gas pedal error, brake force error, and brake response time. Participants were categorized into cognitively normal and cognitively impaired groups (n=10 each). Driving behavior was assessed using the Driving Habits Questionnaire (DHQ), and crash risk was determined via UFOV classification. Increased gas pedal error was associated with poorer MoCA scores and selective attention deficits. Delayed brake response times correlated with lower MoCA scores and poorer divided and selective attention. Although self-reported driving behavior was comparable between groups, 60% of cognitively impaired participants demonstrated moderate to high crash risk compared to cognitively normal participants, who exhibited low crash risk. Cognitive impairment after stroke is significantly linked to impaired lower limb control during driving and elevated crash risk. These findings highlight an urgent need to integrate cognitive assessment along with motor assessments in post-stroke rehabilitation. Future advances in neuroengineering technologies, and personalized motor-cognitive interventions could play a critical role in restoring safe driving capabilities and mobility independence after stroke.

BackgroundThe relationship between the functional recovery of patients in the subacute phase of stroke and descending neural drives from the non-injured hemisphere to the paretic lower limb muscles during movement remains unclear. We investigated this relationship in patients with severe paralysis.MethodsTwenty-nine patients with stroke were recruited and categorized into three groups based on paralysis severity. Within 1 month of admission, each patient received 10 min of anodal tDCS applied to the cortical motor areas of the injured or non-injured hemispheres. Each stimulation condition was performed in a random order, one day at a time, with a 7-day washout period. Before and after each stimulation, patients performed multiple voluntary knee extensions on the paretic side 20% of their maximal strength, sustained for 6 s. Coherence analysis of EMG signals from proximal and distal segments of the vastus medialis muscle was conducted to quantify common neural drive from each cortical motor-related area based on coherence variations before and post stimulation in each condition. We investigated the relationship between the excitability of the descending neural pathway from the non-injured hemisphere in the initial phase and motor function recovery at 3 months.ResultsNo significant differences emerged across groups in the change in coherence values when the non-injured hemisphere stimulated. However, within the severe group, an increase in β-band coherence following non-injured hemisphere stimulation correlated with greater recovery of paretic-side muscle strength and trunk function at 3 months.ConclusionOur findings deepen understanding of paralysis pathophysiology based on severity level and may support the development of targeted neuromodulation strategies to enhance motor recovery.

BackgroundRepetitive transcranial magnetic stimulation (rTMS) is a noninvasive intervention aimed at enhancing neuroplasticity and supporting motor recovery in stroke survivors. This meta-analysis examines the efficacy of rTMS in enhancing upper limb motor function and independance in daily activities, utilizing key assessment tools such as the Fugl-Meyer Assessment for Upper Extremity (FMA-UE), Wolf Motor Function Test (WMFT), Modified Barthel Index (MBI), and Action Research Arm Test (ARAT).MethodsA systematic review of 10 studies involving 382 participants was conducted. Outcomes were analyzed for mean differences (MD) and 95% confidence intervals (CI) using forest plots. Subgroup analyses examined the influence of stroke stage and session length. Evidence quality was assessed using the GRADE framework.ResultsrTMS significantly improved motor performance, with the FMA-UE showing the most consistent and clinically meaningful gains, where the overall standardized mean difference (SMD) was 1.28 (95% CI: 1.82 to 0.74, p < 0.0001, I² = 0%), particularly during subacute and subacute-to-chronic stages. Furthermore, protocols with 15-20 sessions yielded significantly better outcomes (SMD = 1.50, 95% CI: 1.90 to 1.10, p < 0.001) than shorter protocols. ARAT results were less consistent, indicating challenges in fine motor recovery, particularly in chronic stroke populations.ConclusionThis meta-analysis confirms that rTMS effectively enhances upper limb motor function and independence in post-stroke patients. Tailored protocols during subacute stages optimize recovery, though further research is needed to refine protocols and explore long-term outcomes.

Altered joint stiffness is common after stroke, yet clinically feasible tools to objectively quantify joint stiffness during walking are lacking. Quasi-stiffness, defined as the slope of the joint torque-angle curve, can serve as a surrogate measure of stiffness; however, it typically requires expensive 3D motion capture systems. 2D motion capture is a potential low-cost alternative for measuring quasi-stiffness in the sagittal plane; however, it is unclear if it can accurately estimate quasi-stiffness in patient populations that often exhibit out-of-plane motions. Therefore, in this study, we aimed to identify the minimal data required to accurately estimate joint quasi-stiffness. To do so, we evaluated the agreement between quasi-stiffness measurements obtained from 3D data in fifteen individuals with chronic stroke and from a simulated set of 2D data reconstructed from the 3D coordinates. Lower-extremity kinematic and kinetic data during overground walking were collected using a 3D motion capture system and an embedded force plate. To simulate 2D data, 3D maker data were projected to a simulated camera lens positioned to view sagittal motions, and medio-lateral components of the ground reaction force data were removed. Joint angles and moments at the hip, knee, and ankle were computed for both datasets using inverse dynamics, and quasi-stiffnesses of these joints were estimated during the stance phase. A linear mixed model was used to evaluate the effects of quantification method (2D, 3D) and stroke limb (paretic, non-paretic) on quasi-stiffness. Bland-Altman analyses and Intraclass correlation coefficients (ICCs) were used to evaluate the agreement between 2D and 3D measurements. The results indicated that 2D quasi-stiffness measurements were generally in agreement with the 3D quasi-stiffness measurements (Δ: -0.008-0.007 Nm/deg/kg; ICC: 0.576-0.927 [range]), although the 2D measurements slightly overestimated quasi-stiffness for some joints. Additionally, we found that quasi-stiffness was significantly higher in the paretic limb when the ankle was plantarflexing (Δ: 0.024 Nm/deg/kg) compared to the non-paretic limb. The results of this study suggest that quasi-stiffness can be validly estimated using 2D data, supporting the development of low-cost 2D systems for clinical settings to measure and monitor joint stiffness after stroke.

As stroke results in deficits spanning multiple functional domains, interventions that promote neuroplasticity-like mechanisms across brain and body systems may optimize recovery. In this perspective, we propose a rehabilitation strategy combining operant conditioning with corticomuscular coherence (CMC), a neurophysiological marker of communication between brain and muscle. CMC reflects the synchrony of descending cortical drive with spinal motor output, serving as a real-time index of volitional control. We assert that reinforcing CMC through operant conditioning can strengthen movement-related neural circuits while simultaneously engaging cognitive systems responsible for motor planning, attention, and error correction. Drawing from motor learning, systems neuroscience, and neuroengineering evidence, we outline the conceptual rationale along with the translational potential and implementation challenges of this CMC-based operant conditioning approach. We posit that this framework offers a biologically plausible strategy to strengthen residual motor capacity and restore functional integration across disrupted circuits connecting brain and body systems.