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Heteronymous inhibition between lower limb muscles is primarily attributed to recurrent inhibitory circuits in humans but could also arise from Golgi tendon organs (GTOs). Distinguishing between recurrent inhibition and mechanical activation of GTOs is challenging because their heteronymous effects are both elicited by stimulation of nerves or a muscle above motor threshold. Here, the unique influence of mechanically activated GTOs was examined by comparing the magnitude of heteronymous inhibition from quadriceps (Q) muscle stimulation onto ongoing soleus electromyographic at five Q stimulation intensities (1.5-2.5× motor threshold) before and after an acute bout of stimulation-induced Q fatigue. Fatigue was used to decrease Q stimulation evoked force (i.e., decreased GTO activation) despite using the same pre-fatigue stimulation currents (i.e., same antidromic recurrent inhibition input). Thus, a decrease in heteronymous inhibition after Q fatigue and a linear relation between stimulation-evoked torque and inhibition both before and after fatigue would support mechanical activation of GTOs as a source of inhibition. A reduction in evoked torque but no change in inhibition would support recurrent inhibition. After fatigue, Q stimulation-evoked knee torque, heteronymous inhibition magnitude and inhibition duration were significantly decreased for all stimulation intensities. In addition, heteronymous inhibition magnitude was linearly related to twitch-evoked knee torque before and after fatigue. These findings support mechanical activation of GTOs as a source of heteronymous inhibition along with recurrent inhibition. The unique patterns of heteronymous inhibition before and after fatigue across participants suggest the relative contribution of GTOs, and recurrent inhibition may vary across persons.
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Electromiografía , Fatiga Muscular , Músculo Cuádriceps , Humanos , Fatiga Muscular/fisiología , Masculino , Adulto , Músculo Cuádriceps/fisiología , Femenino , Músculo Esquelético/fisiología , Adulto Joven , Inhibición Neural/fisiología , Estimulación Eléctrica , TorqueRESUMEN
BACKGROUND AND PURPOSE: Implantable vagus nerve stimulation (VNS) paired with volitional upper extremity rehabilitation can improve impairment and function among moderately to severely impaired, chronic stroke survivors. This study is a retrospective analysis of the in-clinic rehabilitation phase of the blinded, placebo-controlled, randomized pivotal VNS-REHAB trial to determine whether dosing parameters during in-clinic paired VNS therapy were associated with responder status and whether covariates might impact that determination. METHODS: Data were limited to 53 participants in the active VNS group who had received VNS implants prior to undergoing 6 weeks of in-clinic rehabilitation paired with VNS. Tasks were standardized across all participants. Dosing parameters included number of stimulations and task time. The primary outcome was the Fugl-Meyer Upper Extremity Assessment (FMA-UE), evaluated at the end of 6 weeks (Post-1). Participants were classified a priori as responders based on an improvement of ≥6 points on the FMA-UE from baseline to Post-1. RESULTS: Dosing parameters were not associated with FMA-UE responder status at the end of 6 weeks. Covariates including age, gender, paretic hand, baseline severity, and chronicity of stroke were also not significant associations of response. DISCUSSION AND CONCLUSIONS: While responders to VNS could be defined, therapy dosing and participant attributes did not provide greater specification for association of responder status. Limitations of this study include small sample size and non-linearity of the FMA-UE. Future studies will include reassessing responder categorization using more linear scales and examining stroke lesion characteristics to determine whether these measures are more sensitive to dosing parameters. VIDEO ABSTRACT AVAILABLE: for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://www.w3.org/1999/xlink).
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OBJECTIVE: To evaluate differences in upper-extremity (UE) segment-specific (proximal or distal segment) recovery after vagus nerve stimulation (VNS) paired with UE rehabilitation (Paired-VNS) compared with rehabilitation with sham-VNS (Control). We also assessed whether gains in specific UE segments predicted clinically meaningful improvement. DESIGN: This study reports on a secondary analysis of Vagus nerve stimulation paired with rehabilitation for UE motor function after chronic ischemic stroke (VNS-REHAB), a randomized, triple-blinded, sham-controlled pivotal trial. A Rasch latent regression was used to determine differences between Paired-VNS and Controls for distal and proximal UE changes after in-clinic therapy and 3 months later. Subsequently, we ran a random forest model to assess candidate predictors of meaningful improvement. Each item of the Fugl-Meyer Assessment-Upper Extremity (FMA-UE) and Wolf Motor Function Test (WMFT) was evaluated as a predictor of response to treatment. SETTING: Nineteen stroke rehabilitation centers in the USA and UK. PARTICIPANTS: Dataset included 108 participants (N=108) with chronic ischemic stroke and moderate-to-severe UE impairments. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: FMA-UE and WMFT. RESULTS: Distal UE improvement was significantly greater in the Paired-VNS group than in Controls immediately after therapy (95% confidence interval, 0.27-0.73; P≤.001) and after 3 months (95% confidence interval, 0.16-0.75; P=.003). Both groups showed similar improvement in proximal UE at both time points. A subset of both distal and proximal items from the FMA-UE and WMFT were predictors of meaningful improvement. CONCLUSIONS: Paired-VNS improved distal UE impairment in chronic stroke to a greater degree than intensive rehabilitation alone. Proximal improvements were equally responsive to either treatment. Given that meaningful UE recovery is predicted by improvements across both proximal and distal segments, Paired-VNS may facilitate improvement that is otherwise elusive.
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BACKGROUND: Long-term loss of arm function after ischaemic stroke is common and might be improved by vagus nerve stimulation paired with rehabilitation. We aimed to determine whether this strategy is a safe and effective treatment for improving arm function after stroke. METHODS: In this pivotal, randomised, triple-blind, sham-controlled trial, done in 19 stroke rehabilitation services in the UK and the USA, participants with moderate-to-severe arm weakness, at least 9 months after ischaemic stroke, were randomly assigned (1:1) to either rehabilitation paired with active vagus nerve stimulation (VNS group) or rehabilitation paired with sham stimulation (control group). Randomisation was done by ResearchPoint Global (Austin, TX, USA) using SAS PROC PLAN (SAS Institute Software, Cary, NC, USA), with stratification by region (USA vs UK), age (≤30 years vs >30 years), and baseline Fugl-Meyer Assessment-Upper Extremity (FMA-UE) score (20-35 vs 36-50). Participants, outcomes assessors, and treating therapists were masked to group assignment. All participants were implanted with a vagus nerve stimulation device. The VNS group received 0·8 mA, 100 µs, 30 Hz stimulation pulses, lasting 0·5 s. The control group received 0 mA pulses. Participants received 6 weeks of in-clinic therapy (three times per week; total of 18 sessions) followed by a home exercise programme. The primary outcome was the change in impairment measured by the FMA-UE score on the first day after completion of in-clinic therapy. FMA-UE response rates were also assessed at 90 days after in-clinic therapy (secondary endpoint). All analyses were by intention to treat. This trial is registered at ClinicalTrials.gov, NCT03131960. FINDINGS: Between Oct 2, 2017, and Sept 12, 2019, 108 participants were randomly assigned to treatment (53 to the VNS group and 55 to the control group). 106 completed the study (one patient for each group did not complete the study). On the first day after completion of in-clinic therapy, the mean FMA-UE score increased by 5·0 points (SD 4·4) in the VNS group and by 2·4 points (3·8) in the control group (between group difference 2·6, 95% CI 1·0-4·2, p=0·0014). 90 days after in-clinic therapy, a clinically meaningful response on the FMA-UE score was achieved in 23 (47%) of 53 patients in the VNS group versus 13 (24%) of 55 patients in the control group (between group difference 24%, 6-41; p=0·0098). There was one serious adverse event related to surgery (vocal cord paresis) in the control group. INTERPRETATION: Vagus nerve stimulation paired with rehabilitation is a novel potential treatment option for people with long-term moderate-to-severe arm impairment after ischaemic stroke. FUNDING: MicroTransponder.
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Neuroestimuladores Implantables/efectos adversos , Accidente Cerebrovascular Isquémico/complicaciones , Rehabilitación de Accidente Cerebrovascular/métodos , Extremidad Superior/fisiopatología , Estimulación del Nervio Vago/instrumentación , Anciano , Estudios de Casos y Controles , Terapia Combinada/métodos , Terapia por Ejercicio/métodos , Femenino , Humanos , Accidente Cerebrovascular Isquémico/rehabilitación , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Paresia/etiología , Recuperación de la Función/fisiología , Resultado del Tratamiento , Parálisis de los Pliegues Vocales/epidemiologíaRESUMEN
Up to 50% of stroke survivors have persistent, severe upper extremity paresis even after receiving rehabilitation. Repetitive transcranial magnetic stimulation (rTMS) can augment the effects of rehabilitation by modulating corticomotor excitability, but the conventional approach of facilitating excitability of the ipsilesional primary motor cortex (iM1) fails to produce motor improvement in stroke survivors with severe loss of ipsilesional substrate. Instead, the undamaged, contralesional dorsal premotor cortex (cPMd) may be a more suitable target. CPMd can offer alternate, bi-hemispheric and ipsilateral connections in support of paretic limb movement. This pilot, randomized clinical trial seeks to investigate whether rTMS delivered to facilitate cPMd in conjunction with rehabilitation produces greater gains in motor function than conventional rTMS delivered to facilitate iM1 in conjunction with rehabilitation in severely impaired stroke survivors. Twenty-four chronic (≥6 months) stroke survivors with severe loss of ipsilesional substrate (defined by the absence of physiologic evidence of excitable residual pathways tested using TMS) will be included. Participants will be randomized to receive rTMS to facilitate cPMd or iM1 in conjunction with task-oriented upper limb rehabilitation given for 2 sessions/week for 6 weeks. Assessments of primary outcome related to motor impairment (upper extremity Fugl-Meyer [UEFM]), motor function, neurophysiology, and functional neuroimaging will be made at baseline and at 6-week end-of-treatment. An additional assessment of motor outcomes will be repeated at 3-month follow-up to evaluate retention. The primary endpoint is 6-week change in UEFM. This pilot trial will provide preliminary evidence on the effects and mechanisms associated with facilitating intact cPMd in chronic severe stroke survivors. The trial is registered on clinicaltrials.gov, NCT03868410.
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Corteza Motora , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Proyectos Piloto , Ensayos Clínicos Controlados Aleatorios como Asunto , Recuperación de la Función/fisiología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Rehabilitación de Accidente Cerebrovascular/métodos , Estimulación Magnética Transcraneal , Resultado del Tratamiento , Extremidad SuperiorRESUMEN
Heteronymous excitatory feedback from muscle spindles and inhibitory feedback from Golgi tendon organs and recurrent inhibitory circuits can influence motor coordination. The functional role of inhibitory feedback is difficult to determine, because nerve stimulation, the primary method used in humans, cannot evoke inhibition without first activating the largest diameter muscle spindle axons. Here, we tested the hypothesis that quadriceps muscle stimulation could be used to examine heteronymous inhibition more selectively when compared to femoral nerve stimulation by comparing the effects of nerve and muscle stimulation onto ongoing soleus EMG held at 20% of maximal effort. Motor threshold and two higher femoral nerve and quadriceps stimulus intensities matched by twitch evoked torque magnitudes were examined. We found that significantly fewer participants exhibited excitation during quadriceps muscle stimulation when compared to nerve stimulation (14-29% vs. 64-71% of participants across stimulation intensities) and the magnitude of heteronymous excitation from muscle stimulation, when present, was much reduced compared to nerve stimulation. Muscle and nerve stimulation resulted in heteronymous inhibition that significantly increased with increasing stimulation evoked torque magnitudes. This study provides novel evidence that muscle stimulation may be used to more selectively examine inhibitory heteronymous feedback between muscles in the human lower limb when compared to nerve stimulation.
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Nervio Femoral , Músculo Cuádriceps , Estimulación Eléctrica , Nervio Femoral/fisiología , Reflejo H/fisiología , Humanos , Husos Musculares/fisiología , Músculo Esquelético/fisiologíaRESUMEN
The American Heart Association/American Stroke Association released the adult stroke rehabilitation and recovery guidelines in 2016. A working group of stroke rehabilitation experts reviewed these guidelines and identified a subset of recommendations that were deemed suitable for creating performance measures. These 13 performance measures are reported here and contain inclusion and exclusion criteria to allow calculation of rates of compliance in a variety of settings ranging from acute hospital care to postacute care and care in the home and outpatient setting.
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Rehabilitación de Accidente Cerebrovascular/normas , Enfermedad Aguda/terapia , Atención Ambulatoria , American Heart Association , Sector de Atención de Salud , Servicios de Atención de Salud a Domicilio , Humanos , Organizaciones , Centros de Rehabilitación , Estados UnidosRESUMEN
OBJECTIVE: To determine the extent to which estimates of sample and effect size in stroke rehabilitation trials can be affected by simple summation of ordinal Upper Extremity Fugl-Meyer (UEFM) items compared with a Rasch-rescaled UEFM. DESIGN: Rasch analysis of Interdisciplinary Comprehensive Arm Rehabilitation Evaluation (ICARE) phase III trial data, comparing 3 upper extremity (UE) motor treatments in stroke survivors enrolled 45.8±22.4 days poststroke. Participants underwent a structured UE motor training known as the Accelerated Skill Acquisition Program, usual and customary care, or dose-equivalent care. UEFM data from baseline, postintervention, and 6 and 12 months later were included for analysis. SETTING: Outpatient stroke rehabilitation. PARTICIPANTS: ICARE participants (N=361). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Item difficulties, person abilities, and sample size. RESULTS: Because of their ordinality, summed raw UEFM scores measured motor impairment inconsistently across different ranges of stroke severity relative to the rescaled UEFM. In the full ICARE sample, raw UEFM understated scores relative to the rescaled UEFM by 7.4 points for the most severely impaired, but overstated scores by up to 8.4 points toward the ceiling. As a result, 50.9% of all UEFM observations showed a residual error greater than 10% of the total UEFM score. Relative to the raw scores, the rescaled UEFM improved the effect size of change in motor impairment between baseline and 1 year (d=0.35). For a hypothetical 3-arm trial resembling ICARE, UEFM rescaling reduced the required sample size by 32% (n=108) compared with raw UEFM (n=159). CONCLUSIONS: In UE rehabilitation trials, a rescaled UEFM potentially decreases sample size by one-third, decreasing costs, duration, and the number of subjects exposed to experimental risks. This benefit is obtained through increased measurement efficiency. Reductions in ceiling effects are also possible. These findings apply to ICARE-like trials. Confirmatory validation in another phase III trial is needed.
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Rehabilitación de Accidente Cerebrovascular/métodos , Extremidad Superior/fisiopatología , Anciano , Atención Ambulatoria , Evaluación de la Discapacidad , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Recuperación de la Función , Proyectos de InvestigaciónRESUMEN
OBJECTIVE: Evaluate the feasibility and potential impacts on hand function using a wearable stimulation device (the VTS Glove) which provides mechanical, vibratory input to the affected limb of chronic stroke survivors. METHODS: A double-blind, randomized, controlled feasibility study including sixteen chronic stroke survivors (mean age: 54; 1-13 years post-stroke) with diminished movement and tactile perception in their affected hand. Participants were given a wearable device to take home and asked to wear it for three hours daily over eight weeks. The device intervention was either (1) the VTS Glove, which provided vibrotactile stimulation to the hand, or (2) an identical glove with vibration disabled. Participants were randomly assigned to each condition. Hand and arm function were measured weekly at home and in local physical therapy clinics. RESULTS: Participants using the VTS Glove showed significantly improved Semmes-Weinstein monofilament exam results, reduction in Modified Ashworth measures in the fingers, and some increased voluntary finger flexion, elbow and shoulder range of motion. CONCLUSIONS: Vibrotactile stimulation applied to the disabled limb may impact tactile perception, tone and spasticity, and voluntary range of motion. Wearable devices allow extended application and study of stimulation methods outside of a clinical setting.
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Modalidades de Fisioterapia/instrumentación , Rehabilitación de Accidente Cerebrovascular/instrumentación , Percepción del Tacto/fisiología , Vibración/uso terapéutico , Dispositivos Electrónicos Vestibles , Anciano , Método Doble Ciego , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tono Muscular , Rango del Movimiento Articular , Rehabilitación de Accidente Cerebrovascular/métodos , Extremidad Superior/fisiopatologíaRESUMEN
OBJECTIVE: To compare participants with Parkinson disease (PD) motor subtypes, postural instability and gait difficulty (PIGD) (n=46) and tremor dominant (TD) (n=28), in cognitive and motor-cognitive assessments with the purpose of identifying associations between subtype and visuospatial, whole-body spatial, inhibition and/or switching, and planning and/or organizational aspects of cognitive and motor-cognitive function. DESIGN: Retrospective cohort study. Fisher exact test was used for categorical variables, while 2-sample independent t tests were used to analyze continuous variables. SETTING: Assessments took place at Emory University. PARTICIPANTS: Participants (N=72) were 40 years and older, had a clinical diagnosis of PD, exhibited 3 of the 4 cardinal signs of PD, had shown benefit from antiparkinsonian medications, and were in Hoehn and Yahr stages I-IV. Participants could walk 3 m or more with or without assistance. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Balance and mobility tests included Fullerton Advanced Balance Scale and the time needed to turn 360 degrees. Cognitive assessments included Montreal Cognitive Assessment, Brooks Spatial Memory Task, Color-Word Interference Test, Tower of London, Trail Making Test, Corsi Blocks, Serial 3s Subtraction, and Body Position Spatial Task. Motor-cognitive function measures included Four Square Step Test and Timed Up and Go. RESULTS: Participants with PIGD performed lower than those with TD symptoms on mental status (P=.005), spatial memory (P=.027), executive function (P=.0001-.034), and visuospatial ability (P=.048). CONCLUSIONS: Findings suggest that PIGD subtype is linked to greater deficits in spatial cognition, attentional flexibility and organizational planning, and whole-body spatial memory domains. These findings support the need for more personalized approaches to clinically managing PD.
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Enfermedad de Parkinson/clasificación , Enfermedad de Parkinson/fisiopatología , Anciano , Agnosia/fisiopatología , Antiparkinsonianos/uso terapéutico , Trastornos del Conocimiento/fisiopatología , Función Ejecutiva/fisiología , Femenino , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Enfermedad de Parkinson/tratamiento farmacológico , Equilibrio Postural/fisiología , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Navegación Espacial/fisiologíaRESUMEN
OBJECTIVE: To adapt the Reaching Performance Scale for Stroke (RPSS) for the Wolf Motor Function Test (WMFT) "Lift Can" (Can) and "Hand to Box" (Box) items. DESIGN: Retrospective analysis of video-recorded WMFT assessment performed by 3 raters on 2 occasions. SETTING: Not applicable. PARTICIPANTS: Participants (N=29) with mild to moderate upper extremity impairment less than 3 months after stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Inter- and intra-rater agreement, concurrent validity of WMFT-RPSS. RESULTS: Mean ± SD inter-rater Gwet's agreement coefficient (AC2) was 0.61±0.05 for Can WMFT-RPSS and 0.56 (0.03) for Box. Mean ± SD intra-rater AC2 for Can was 0.63±0.05 and 0.70±0.04 for Box. WMFT-RPSS Can and Box scores correlated with log mean WMFT time (C, -0.73; B, -0.48), Functional Ability Scale (C, 0.87; B, 0.62), Upper Extremity Fugl-Meyer Motor Score (C, 0.69; B, 0.51), and item movement rate (C, 0.74; B, 0.71) (P<.05 for all). Mean ± SD WMFT-RPSS score across the 29 participants was 12.7±3.5 for Can (max score, 19) and 11.4±3.0 for Box (max score, 16). CONCLUSIONS: WMFT-RPSS demonstrated moderate intra-rater and weak-to-moderate inter-rater agreement for individuals with mild-moderate impairment. For construct validity, Can and Box WMFT-RPSS were significantly correlated with 4 standardized measures. Average WMFT-RPSS scores revealed that some participants may have relied on compensatory movements to complete the task, a revelation not discernable from movement rate alone. The WMFT-RPSS is potentially useful as a valid and reliable tool to examine longitudinal changes in movement quality after stroke.
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Evaluación de la Discapacidad , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/fisiopatología , Análisis y Desempeño de Tareas , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuperación de la Función , Reproducibilidad de los Resultados , Estudios Retrospectivos , Extremidad Superior/fisiopatologíaRESUMEN
The growing field of regenerative rehabilitation has great potential to improve clinical outcomes for individuals with disabilities. However, the science to elucidate the specific biological underpinnings of regenerative rehabilitation-based approaches is still in its infancy and critical questions regarding clinical translation and implementation still exist. In a recent roundtable discussion from International Consortium for Regenerative Rehabilitation stakeholders, key challenges to progress in the field were identified. The goal of this article is to summarize those discussions and to initiate a broader discussion among clinicians and scientists across the fields of regenerative medicine and rehabilitation science to ultimately progress regenerative rehabilitation from an emerging field to an established interdisciplinary one. Strategies and case studies from consortium institutions-including interdisciplinary research centers, formalized courses, degree programs, international symposia, and collaborative grants-are presented. We propose that these strategic directions have the potential to engage and train clinical practitioners and basic scientists, transform clinical practice, and, ultimately, optimize patient outcomes.
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Medicina Regenerativa/tendencias , Rehabilitación/tendencias , Certificación , Congresos como Asunto , Curriculum , Becas , Humanos , Medicina Regenerativa/educación , Rehabilitación/educaciónRESUMEN
Real-time biofeedback is a promising post-stroke gait rehabilitation strategy that can target specific gait deficits preferentially in the paretic leg. Our previous work demonstrated that the use of an audiovisual biofeedback interface designed to increase paretic leg propulsion, measured via anterior ground reaction force (AGRF) generation during late stance phase of gait, can induce improvements in peak AGRF production of the targeted and paretic limb of able-bodied and post-stroke individuals, respectively. However, whether different modes of biofeedback, such as visual, auditory, or a combination of both, have differential effects on AGRF generation is unknown. The present study investigated the effects of audio only, visual only, or audiovisual AGRF biofeedback in able-bodied and post-stroke individuals. Seven able-bodied (6 females, 27 ± 2 years) and nine post-stroke individuals (6 females, 54 ± 12 years, 42 ± 26 months post-stroke) completed four 30-s walking trials on a treadmill under 4 conditions: no biofeedback, audio biofeedback, visual biofeedback, or audiovisual biofeedback. Compared to walking without biofeedback, all three biofeedback modes significantly increased peak AGRF in the targeted and paretic leg. There was no significant difference in peak AGRF between the three biofeedback modes. Able-bodied individuals demonstrated greater feedback-induced increase in stride-to-stride variation of AGRF generation during audio biofeedback compared to visual biofeedback; however, similar results were not observed in the post-stroke group. The present findings may inform future development of real-time gait biofeedback interfaces for use in clinical or community environments.
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Percepción Auditiva/fisiología , Biorretroalimentación Psicológica/métodos , Fenómenos Biomecánicos/fisiología , Trastornos Neurológicos de la Marcha/rehabilitación , Marcha/fisiología , Rehabilitación de Accidente Cerebrovascular/métodos , Percepción Visual/fisiología , Adulto , Anciano , Retroalimentación Sensorial/fisiología , Femenino , Trastornos Neurológicos de la Marcha/etiología , Humanos , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/terapia , Resultado del TratamientoRESUMEN
Spinal pathways underlying reciprocal flexion-extension contractions have been well characterized, but the extent to which cortically evoked motor-evoked potentials (MEPs) are influenced by antagonist muscle activation remains unclear. A majority of studies using transcranial magnetic stimulation- (TMS-) evoked MEPs to evaluate the excitability of the corticospinal pathway focus on upper extremity muscles. Due to functional and neural control differences between lower and upper limb muscles, there is a need to evaluate methodological factors influencing TMS-evoked MEPs specifically in lower limb musculature. If and to what extent the activation of the nontargeted muscles, such as antagonists, affects TMS-evoked MEPs is poorly understood, and such gaps in our knowledge may limit the rigor and reproducibility of TMS studies. Here, we evaluated the effect of the activation state of the antagonist muscle on TMS-evoked MEPs obtained from the target (agonist) ankle muscle for both tibialis anterior (TA) and soleus muscles. Fourteen able-bodied participants (11 females, age: 26.1 ± 4.1 years) completed one experimental session; data from 12 individuals were included in the analysis. TMS was delivered during 4 conditions: rest, TA activated, soleus activated, and TA and soleus coactivation. Three pairwise comparisons were made for MEP amplitude and coefficient of variability (CV): rest versus coactivation, rest versus antagonist activation, and agonist activation versus coactivation. We demonstrated that agonist-antagonist coactivation enhanced MEP amplitude and reduced MEP CVs for both TA and soleus muscles. Our results provide methodological considerations for future TMS studies and pave the way for future exploration of coactivation-dependent modulation of corticomotor excitability in pathological cohorts such as stroke or spinal cord injury.
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Articulación del Tobillo/fisiología , Tobillo/fisiología , Potenciales Evocados Motores/fisiología , Contracción Muscular/fisiología , Adulto , Femenino , Humanos , Extremidad Inferior/fisiología , Masculino , Corteza Motora/fisiología , Tractos Piramidales/fisiología , Estimulación Magnética Transcraneal/métodos , Adulto JovenRESUMEN
OBJECTIVE: To assess the feasibility of conducting a randomized controlled trial of an instructional and educational stroke DVD and determine the feasibility and preliminary efficacy of this intervention in a multinational context. DESIGN: Non-funded, pilot randomized controlled trial of intervention versus usual care. SETTING: International, multicentre, community-based. PARTICIPANTS: Community-living adults up to three years post stroke with moderate to severe disability and their nominated informal caregivers. INTERVENTIONS: Intervention patients viewed and practised rehabilitation techniques demonstrated in the DVD over six weeks. MAIN MEASURES: Trial feasibility by number of active recruitment sites, recruitment efficiency, randomization and follow-up. Intervention feasibility by patient and caregiver impressions. Preliminary efficacy by the quality of life - 5-level EuroQol-5D (EQ-5D) health status measure, General Health Questionnaire and Centre for Epidemiological Studies-Depression at two months. RESULTS: In total, 14 recruitment sites were established across eight countries. Recruitment was achieved at nine (64%) sites. Over 16 months, 66 participants were recruited (mean (SD) age = 63.5 (12.47) years) and randomized to intervention ( n = 34) and control ( n = 32) groups. In total, 54 (82%) completed a follow-up assessment. Patient and/or caregiver comments about the benefits and barriers to accessing the intervention were mixed. There were no significant between-group differences in outcomes at two months ( P > 0.05). CONCLUSION: Conducting a multinational trial of a stroke DVD requires full funding. The intervention was acceptable to some patients and their caregivers, yet a generalized education approach did not fully meet their needs and/or expectations. A more individualized method may be required to meet peoples' changing needs during stroke recovery.
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Educación del Paciente como Asunto , Rehabilitación de Accidente Cerebrovascular/métodos , Terapia Asistida por Computador/métodos , Cuidadores , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios ProspectivosRESUMEN
Background: Despite intensive rehabilitation efforts, most stroke survivors have persistent functional disability of the paretic arm and hand. These motor impairments may be due in part to maladaptive changes in structural and functional connections between brain regions. The following early stage clinical trial study protocol describes a noninvasive brain stimulation approach to target transcallosally mediated interhemispheric connections between the ipsi- and contralesional motor cortices (iM1 and cM1) using corticocortical paired associative stimulation (ihPAS). This clinical trial aims to characterize ihPAS-induced modulation of interhemispheric connectivity and the effect on motor skill performance and learning in chronic stroke survivors. Methods/Design: A repeated-measures, cross-over design study will recruit 20 individuals post-stroke with chronic mild-moderate paretic arm impairment. Each participant will complete an active ihPAS and control ihPAS session. Assessments of cortical excitability and motor skill performance will be conducted prior to and at four time points following the ihPAS intervention. The primary outcome measures will be: TMS-evoked interhemispheric motor connectivity, corticomotor excitability, and response time on a modified serial reaction time task. Discussion/Conclusion: The findings from this single-site early stage clinical trial will provide foundational results to inform the design of larger-scale, multisite clinical trials to evaluate the therapeutic potential of ihPAS-based neuromodulation for upper limb recovery after stroke. This trial is registered with NCT02465034.
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Brazo/fisiopatología , Encéfalo/fisiopatología , Plasticidad Neuronal/fisiología , Paresia/rehabilitación , Recuperación de la Función/fisiología , Rehabilitación de Accidente Cerebrovascular/métodos , Estimulación Magnética Transcraneal/métodos , Adulto , Anciano , Anciano de 80 o más Años , Protocolos Clínicos , Estudios Cruzados , Potenciales Evocados Motores/fisiología , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Persona de Mediana Edad , Paresia/etiología , Paresia/fisiopatología , Proyectos de Investigación , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/fisiopatologíaRESUMEN
OBJECTIVE: To investigate the measurement properties of the Functional Test of the Hemiparetic Upper Extremity (FTHUE) and examine how its score may or may not inform design of a rehabilitation program. DESIGN: The FTHUE was recently used in the Interdisciplinary Comprehensive Arm Rehabilitation Evaluation randomized controlled trial. This circumstance provided the opportunity to examine the psychometric properties of the FTHUE as it pertains to contemporary poststroke rehabilitation and recovery models. SETTING: Outpatient rehabilitation clinic. PARTICIPANTS: Participants (N=109; mean age, 61.2±13.5y; mean days poststroke, 46±20.3) with resultant hemiparesis in the upper extremity. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Dimensionality was examined with confirmatory factor analysis (CFA), and person and item measures were derived with Rasch item response analysis. Therapists' notes were also reviewed. RESULTS: The CFA results support unidimensionality, and 16 of 17 items fit the Rasch model. The Rasch person separation (2.17) and item separation (4.50) indices, ability strata (3.22), person reliability (.82), and item reliability (.95) indicate good measurement properties. Item difficulties ranked from -6.46 to 3.43 logits; however, there was a substantial ceiling effect of person measures. Post hoc examination of therapists' written observations indicated that the scoring criteria are not sensitive to the movement strategy used for task completion. CONCLUSIONS: The FTHUE's item difficulty hierarchy indicated that scores adequately distinguished the ability to perform simple versus complex motor movements of functional tasks. However, the FTHUE scoring method did not allow inclusion of the type of movement strategy used to accomplish task items. Therefore, we suggest modifications to the FTHUE that would allow it to be used for collaborative treatment planning and align well with more contemporary perspectives on treatment theory.
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Evaluación de la Discapacidad , Paresia/fisiopatología , Accidente Cerebrovascular/fisiopatología , Extremidad Superior/fisiopatología , Análisis Factorial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Reproducibilidad de los ResultadosRESUMEN
IMPORTANCE: Clinical trials suggest that higher doses of task-oriented training are superior to current clinical practice for patients with stroke with upper extremity motor deficits. OBJECTIVE: To compare the efficacy of a structured, task-oriented motor training program vs usual and customary occupational therapy (UCC) during stroke rehabilitation. DESIGN, SETTING, AND PARTICIPANTS: Phase 3, pragmatic, single-blind randomized trial among 361 participants with moderate motor impairment recruited from 7 US hospitals over 44 months, treated in the outpatient setting from June 2009 to March 2014. INTERVENTIONS: Structured, task-oriented upper extremity training (Accelerated Skill Acquisition Program [ASAP]; n = 119); dose-equivalent occupational therapy (DEUCC; n = 120); or monitoring-only occupational therapy (UCC; n = 122). The DEUCC group was prescribed 30 one-hour sessions over 10 weeks; the UCC group was only monitored, without specification of dose. MAIN OUTCOMES AND MEASURES: The primary outcome was 12-month change in log-transformed Wolf Motor Function Test time score (WMFT, consisting of a mean of 15 timed arm movements and hand dexterity tasks). Secondary outcomes were change in WMFT time score (minimal clinically important difference [MCID] = 19 seconds) and proportion of patients improving ≥25 points on the Stroke Impact Scale (SIS) hand function score (MCID = 17.8 points). RESULTS: Among the 361 randomized patients (mean age, 60.7 years; 56% men; 42% African American; mean time since stroke onset, 46 days), 304 (84%) completed the 12-month primary outcome assessment; in intention-to-treat analysis, mean group change scores (log WMFT, baseline to 12 months) were, for the ASAP group, 2.2 to 1.4 (difference, 0.82); DEUCC group, 2.0 to 1.2 (difference, 0.84); and UCC group, 2.1 to 1.4 (difference, 0.75), with no significant between-group differences (ASAP vs DEUCC: 0.14; 95% CI, -0.05 to 0.33; P = .16; ASAP vs UCC: -0.01; 95% CI, -0.22 to 0.21; P = .94; and DEUCC vs UCC: -0.14; 95% CI, -0.32 to 0.05; P = .15). Secondary outcomes for the ASAP group were WMFT change score, -8.8 seconds, and improved SIS, 73%; DEUCC group, WMFT, -8.1 seconds, and SIS, 72%; and UCC group, WMFT, -7.2 seconds, and SIS, 69%, with no significant pairwise between-group differences (ASAP vs DEUCC: WMFT, 1.8 seconds; 95% CI, -0.8 to 4.5 seconds; P = .18; improved SIS, 1%; 95% CI, -12% to 13%; P = .54; ASAP vs UCC: WMFT, -0.6 seconds, 95% CI, -3.8 to 2.6 seconds; P = .72; improved SIS, 4%; 95% CI, -9% to 16%; P = .48; and DEUCC vs UCC: WMFT, -2.1 seconds; 95% CI, -4.5 to 0.3 seconds; P = .08; improved SIS, 3%; 95% CI, -9% to 15%; P = .22). A total of 168 serious adverse events occurred in 109 participants, resulting in 8 patients withdrawing from the study. CONCLUSIONS AND RELEVANCE: Among patients with motor stroke and primarily moderate upper extremity impairment, use of a structured, task-oriented rehabilitation program did not significantly improve motor function or recovery beyond either an equivalent or a lower dose of UCC upper extremity rehabilitation. These findings do not support superiority of this program among patients with motor stroke and primarily moderate upper extremity impairment. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00871715.
Asunto(s)
Trastornos de la Destreza Motora/rehabilitación , Terapia Ocupacional/métodos , Accidente Cerebrovascular/complicaciones , Anciano , Brazo/fisiopatología , Femenino , Mano/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Destreza Motora , Trastornos de la Destreza Motora/etiología , Recuperación de la Función , Método Simple Ciego , Análisis y Desempeño de TareasRESUMEN
The use of low-cost interactive game technology for balance rehabilitation has become more popular recently, with generally good outcomes. Very little research has been undertaken to determine whether this technology is appropriate for balance assessment. The Wii balance board has good reliability and is comparable to a research-grade force plate; however, recent studies examining the relationship between Wii Fit games and measures of balance and mobility demonstrate conflicting findings. This study found that the Wii Fit was feasible for community-dwelling older women to safely use the balance board and quickly learn the Wii Fit games. The Ski Slalom game scores were strongly correlated with several balance and mobility measures, whereas Table Tilt game scores were not. Based on these findings, the Ski Slalom game may have utility in the evaluation of balance problems in community-dwelling older adults.