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Background: The efficacy of locomotor rehabilitation studies has largely been based on clinical measures of gait speed and walking performance. Although critical, gait speed does not fully capture the multidimensional benefits associated with walking recovery. The International Classification of Function, Disability and Health (ICF) model of rehabilitation emphasizes the role of personal and environmental factors in affecting quality of life and personal health status and advocates a broad approach in the assessment and treatment of people with disabling conditions.Objective: The purpose of this case report is to describe a multidimensional approach to outcome measurement reflecting the ICF model.Subject: The participant was a 59-year-old man with C7 American Spinal Injury Association impairment D tetraplegia, 16 months after injury.Intervention: The participant completed a 45-session, five days per week locomotor training program. Comprehensive evaluations were completed pre- and post-training targeting all elements of the ICF model.Outcomes: The participant achieved negligible increases in gait speed, but increased self-elected walking activity from 26 steps per day to 1273 steps per day. His assistive device changed from a platform to a rolling walker, representing a Walking Index for Spinal Cord Injury (WISCI) increase from 8/20 to 13/20. Qualitative interviews illustrated an attitudinal shift, leading to improved motivation, confidence, self-esteem, problem-solving, and increased activities/participation in the community. Ultimately, the participant was able to transition from nursing home placement to living independently.Conclusions: This case report emphasizes the need to move beyond traditional models for evaluation at the impairment and clinical level to examine the effects of interventions on independence, community integration, and quality of life. [ABSTRACT FROM AUTHOR]

This study examined the experiences of persons with incomplete spinal cord injury who participated in locomotor training (LT). LT is an emerging rehabilitation intervention for enhancing the recovery of walking in persons with central nervous system disorders. Multiple interviews and field observations provided data from eight participants, including four veterans. Findings indicate that experiences of bodily changes were prevalent among participants. Themes included (1) experiencing impaired or absent proprioception, (2) struggling for bodily control, and (3) experiencing emergent bodily sensations. Themes 1 and 2 reflected bodily disruption as a result of spinal cord injury and were challenging to participants as they attempted to reconnect the body and self through LT. Theme 3 reflected bodily sensations (burning, soreness) that were seen as positive signs of recovery and resulted in hope and motivation. Understanding how LT participants experience bodily changes may enable therapists to develop improved participant-centered intervention approaches. [ABSTRACT FROM AUTHOR]

Plantarflexors provide propulsion during walking and receive input from both corticospinal and corticoreticulospinal tracts, which exhibit some frequency-specificity that allows potential differentiation of each tract's descending drive. Given that stroke may differentially affect each tract and impair the function of plantarflexors during walking; here, we examined this frequency-specificity and its relation to walking-specific measures during post-stroke walking. Fourteen individuals with chronic stroke walked on an instrumented treadmill at self-selected and fast walking speed (SSWS and FWS, respectively) while surface electromyography (sEMG) from soleus (SOL), lateral gastrocnemius (LG), and medial gastrocnemius (MG) and ground reaction forces (GRF) were collected. We calculated the intermuscular coherences (IMC; alpha, beta, and low-gamma bands between SOL-LG, SOL-MG, LG-MG) and propulsive impulse using sEMG and GRF, respectively. We examined the interlimb and intralimb IMC comparisons and their relationships with propulsive impulse and walking speed. Interlimb IMC comparisons revealed that beta LG-MG (SSWS) and low-gamma SOL-LG (FWS) IMCs were degraded on the paretic side. Intralimb IMC comparisons revealed that only alpha IMCs (both speeds) exhibited a statistically significant difference to random coherence. Further, alpha LG-MG IMC was positively correlated with propulsive impulse in the paretic limb (SSWS). Alpha and beta/low-gamma bands may have a differential functional role, which may be related to the frequency-specificity of the underlying descending drives. The persistence of alpha band in plantarflexors and its strong positive relationship with propulsive impulse suggests relative alteration of corticoreticulospinal tract after stroke. These findings imply the presence of frequency-specific descending drives to walking-specific muscles in chronic stroke., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: Poststroke fatigue (PSF) contributes to increased mortality and reduces participation in rehabilitative therapy. Although PSF's negative influences are well known, there are currently no effective evidence-based treatments for PSF. The lack of treatments is in part because of a dearth of PSF pathophysiological knowledge. Increasing our understanding of PSF's causes may facilitate and aid the development of effective therapies., Methods: Twenty individuals, >6 months post stroke, participated in this cross-sectional study. Fourteen participants had clinically relevant pathological PSF, based on fatigue severity scale (FSS) scores (total score ≥36). Single-pulse and paired-pulse transcranial magnetic stimulation were used to measure hemispheric asymmetries in resting motor threshold, motor evoked potential amplitude, and intracortical facilitation (ICF). Asymmetry scores were calculated as the ratios between lesioned and nonlesioned hemispheres. The asymmetries were then correlated (Spearman rho) to FSS scores., Results: In individuals with pathological PSF ( N = 14, range of total FSS scores 39-63), a strong positive correlation ( rs = 0.77, P = 0.001) between FSS scores and ICF asymmetries was calculated., Conclusions: As the ratio of ICF between the lesioned and nonlesioned hemispheres increased so did self-reported fatigue severity in individuals with clinically relevant pathological PSF. This finding may implicate adaptive/maladaptive plasticity of the glutamatergic system/tone as a contributor to PSF. This finding also suggests that future PSF studies should incorporate measuring facilitatory activity and behavior in addition to the more commonly studied inhibitory mechanisms. Further investigations are required to replicate this finding and identify the causes of ICF asymmetries., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 by the American Clinical Neurophysiology Society.)

Background: Ankle dorsiflexion function during swing phase contributes to foot clearance and plays an important role in walking ability post-stroke. Commonly used biomechanical measures such as foot clearance and ankle joint excursion have limited ability to accurately evaluate impaired dorsiflexor function., Research Question: Can ankle angular velocity and acceleration be used as reliable measurers of dorsiflexion function in post-stroke gait?, Methods: Using linear regression and Pearson's correlation we retrospectively compared peak ankle angular velocity (Aω P ), peak ankle angular acceleration (Aα P ), peak dorsiflexion angle (DFA P ) and peak foot clearance (FCL P ) as direct measures for swing phase dorsiflexor function in 60 chronic stroke survivors. Intraclass correlation coefficient (ICC) analysis was used for test-retest reliability of Aω P and Aα P. RESULTS: Linear regression models revealed that Aω P , Aα P , DFA P , FCL P had a significant relationship (p < 0.05) with impaired dorsiflexion function. Aα P and DFA P accounted for the most variance of dorsiflexion function. Aω P , Aα P , FCL P , correlated significantly with all clinical outcome measures of walking ability. DFA P had a positive correlation only with FMA-LE. Post-hoc William's t-tests, used to compare the magnitude of difference between two non-independent correlations, revealed that the correlation between all clinical measures and DFA P were significantly weaker than with Aω P and Aα P . Correlation between FMA-LE and FCL P was weaker than with Aω P and Aα P . Excellent test-retest reliability for both Aω P (ICC = 0.968) and Aα P (ICC = 0.947) was observed., Significance: These results suggest that DFA P may only be associated with dorsiflexion function during non-task specific isolated movements, but not during walking. FCL P is associated with dorsiflexion function and walking ability measures but not as strongly as Aω P and Aα P possibly because FCL P is influenced by contribution from hip and knee joint movements. Therefore, Aω P and Aα P are reliable measures and represent dorsiflexion function more accurately than DFA P , and FCL P ., Competing Interests: Declaration of Competing Interest The authors have no disclosures to report., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The purpose of this investigation was to elucidate the relationship between the resting motor threshold (rMT) and active motor threshold (aMT). A cross-sectional comparison of MTs measured at four states of lower extremity muscle activation was conducted: resting, 5% maximal voluntary contraction (MVC), 10%MVC, and standing. MTs were measured at the tibialis anterior in the ipsilesional and contralesional limbs in participants in the chronic phase (>6 months) of stroke ( n = 11) and in the dominant limb of healthy controls ( n = 11). To compare across activation levels, the responses were standardized using averaged peak-to-peak background electromyography (EMG) activity measured at 10%MVC + 2SD for each participant, in addition to the traditional 0.05 mV criterion for rMT (rMT 50 ). In all participants, as muscle activation increased, the least square mean estimates of MTs decreased (contralesional: p = 0.008; ipsilesional: p = 0.0015, healthy dominant: p < 0.0001). In healthy controls, rMT 50 was significantly different from all other MTs ( p < 0.0344), while in stroke, there were no differences in either limb ( p > 0.10). This investigation highlights the relationship between rMT and aMTs, which is important as many stroke survivors do not present with an rMT, necessitating the use of an aMT. Future works may consider the use of the standardized criterion that accounted for background EMG activity across activation levels.

Objective: To determine whether the measurement properties of an instrument that combines items from the Berg Balance Scale (BBS) and the Functional Gait Assessment (FGA) called the Functional Balance Ability Measure (FBAM) supports measuring balance across the functional mobility spectrum ., Design: Retrospective cohort., Setting: Item-level data were from an archival research database., Participants: Ambulatory individuals (N=93, BBS=50 [29-56], FGA=16 [0-30], Fugl-Meyer Assessment of Lower Extremities=27 [14-34], self-selected walking speed=0.4±0.2 m/s, mean age ± SD, 61.7±11.3y; 30.1% female) with chronic stroke (≥6 months)., Interventions: Not applicable., Main Outcome Measures: Unidimensionality was evaluated with a principal components analysis (PCA) of residuals. FBAM rating-scale characteristics, item hierarchy, item and person fit, and person separation were investigated using the Andrich Rating Scale Model., Results: PCA findings indicate the FBAM is sufficiently unidimensional. Rating scale structure was appropriate without modifying the original BBS and FGA scoring systems. Item hierarchy aligned with clinical and theoretical predictions (hardest item: FGA-gait with narrow base of support, easiest item: BBS-sitting unsupported). One item (BBS-standing on 1 foot) misfit, however, removal marginally affected person measures and model statistics. The FBAM demonstrated high person reliability (0.9) and 6 people (∼6%) misfit the expected response pattern. The FBAM separated participants into 4 statistically distinct strata, without a floor or ceiling effect., Conclusions: The FBAM is a unidimensional measure for balance ability across a continuum of functional tasks. Rating-scale characteristics, item hierarchy, item and person fit, and person separation support the FBAM's measurement properties in persons with chronic stroke. Future work should investigate measurement with fewer items and whether the FBAM addresses barriers to adoption of standardized balance measures in clinical practice., (© 2023 The Authors.)

Purpose: Transcranial direct current stimulation (tDCS) has mixed effects on walking performance in individuals poststroke. This is likely the result of variations in tDCS electrode montages and individualized responses. The purpose of this study was to quantify the effects of a single session of tDCS using various electrode montages on poststroke walking performance., Methods: Individuals with chronic stroke ( n = 16) participated in a double-blind, randomized cross-over study with sham stimulation and three tDCS electrode montages. Gait speed, paretic step ratio, and paretic propulsion were assessed prestimulation and poststimulation at self-selected and fastest comfortable speeds. Changes in muscle activation patterns with self-selected walking were quantified by the number of modules derived from nonnegative matrix factorization of EMG signals for hypothesis generation., Results: There was no significant effect of active stimulation montages compared with sham. Comparisons between each participant's best response to tDCS and sham show personalized tDCS may have a positive effect on fastest comfortable overground gait speed ( P = 0.084), paretic step ratio ( P = 0.095) and paretic propulsion ( P = 0.090), and self-selected paretic step ratio ( P = 0.012). Participants with two or three modules at baseline increased module number in response to the all experimental montages and sham, but responses were highly variable., Conclusions: A single session of tDCS may affect clinical and biomechanical walking performance, but effects seem to be dependent on individual response variability to different electrode montages. Findings of this study are consistent with responses to various tDCS electrode montages being the result of underlying neuropathology, and the authors recommend examining how individual factors affect responses to tDCS., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2021 by the American Clinical Neurophysiology Society.)

Background: Mass flexion-extension co-excitation patterns during walking are often seen as a consequence of stroke, but there is limited understanding of the specific contributions of different descending motor pathways toward their control. The corticospinal tract is a major descending motor pathway influencing the production of normal sequential muscle coactivation patterns for skilled movements. However, control of walking is also influenced by non-corticospinal pathways such as the corticoreticulospinal pathway that possibly contribute toward mass flexion-extension co-excitation patterns during walking. The current study sought to investigate the associations between damage to corticospinal (CST) and corticoreticular (CRP) motor pathways following stroke and the presence of mass flexion-extension patterns during walking as evaluated using module analysis., Methods: Seventeen healthy controls and 44 stroke survivors were included in the study. We used non-negative matrix factorization for module analysis of paretic leg electromyographic activity. We typically have observed four modules during walking in healthy individuals. Stroke survivors often have less independently timed modules, for example two-modules presented as mass flexion-extension pattern. We used diffusion tensor imaging-based analysis where streamlines connecting regions of interest between the cortex and brainstem were computed to evaluate CST and CRP integrity. We also used a coarse classification tree analysis to evaluate the relative CST and CRP contribution toward module control., Results: Interhemispheric CST asymmetry was associated with worse lower extremity Fugl-Meyer score ( p = 0.023), propulsion symmetry ( p = 0.016), and fewer modules ( p = 0.028). Interhemispheric CRP asymmetry was associated with worse lower extremity Fugl-Meyer score ( p = 0.009), Dynamic gait index ( p = 0.035), Six-minute walk test ( p = 0.020), Berg balance scale ( p = 0.048), self-selected walking speed ( p = 0.041), and propulsion symmetry ( p = 0.001). The classification tree model reveled that substantial ipsilesional CRP or CST damage leads to a two-module pattern and poor walking ability with a trend toward increased compensatory contralesional CRP based control., Conclusion: Both CST and CRP are involved with control of modules during walking and damage to both may lead to greater reliance on the contralesional CRP, which may contribute to a two-module pattern and be associated with worse walking performance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Srivastava, Seamon, Marebwa, Wilmskoetter, Bowden, Gregory, Seo, Hanlon, Bonilha, Brown, Neptune and Kautz.)

Interpreting change is a requisite component of clinical decision making for physical therapists. Physical therapists often interpret change using minimal detectable change (MDC) values. Current MDC formulas are informed by classical test theory and calculated with group-level error data. This approach assumes that measurement error is the same across a measure's scale and confines the MDC value to the sample characteristics of the study. Alternatively, an item response theory (IRT) approach calculates separate estimates of measurement error for different locations on a measure's scale. This generates a conditional measurement error for someone with a low, middle, or high score. Error estimates at the measure-level can then be used to determine a conditional MDC (cMDC) value for individual patients based on their unique pre- and post-score combination. cMDC values can supply clinicians with a means for using individual score data to interpret change scores while providing a personalized approach that should lower the threshold for change compared with the MDC and enhance the precision of care decisions by preventing misclassification of patients. The purpose of this Perspective is to present how IRT can address the limitations of MDCs for informing clinical practice. This Perspective demonstrates how cMDC values can be generated from item-level psychometrics derived from an IRT model using the patient-reported Activities-specific Balance Scale (ABC) commonly used in stroke rehabilitation and also illustrates how the cMDC compares to the MDC when accounting for changes in measurement error across a scale. Theoretical patient examples highlight how reliance on the MDC value can result in misclassification of patient change and how cMDC values can help prevent this from occurring. This personalized approach for interpreting change can be used by physical therapists to enhance the precision of care decisions., (© The Author(s) 2022. Published by Oxford University Press on behalf of the American Physical Therapy Association. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The COVID-19 pandemic has disrupted non-essential in-person research activities that require contact with human subjects. While guidelines are being developed for ramping up human subjects research, one component of research that can be performed remotely is participant screening for lower limb function and gait impairments. In this commentary, we summarize evidence-supported clinical assessments that have potential to be conducted remotely in a safe manner, to make an initial determination of the functional mobility status of persons with neurological disorders. We present assessments that do not require complex or costly equipment, specialized software, or trained personnel to administer. We provide recommendations to implement remote functional assessments for participant recruitment and continuation of lower limb neurorehabilitation research as a rapid response to the COVID-19 pandemic and for utilization beyond the current pandemic. We also highlight critical research gaps related to feasibility and measurement characteristics of remote lower limb assessments, providing opportunities for future research to advance tele-assessment and tele-rehabilitation.

Transcranial magnetic stimulation (TMS) is a common tool used to measure the behavior of motor circuits in healthy and neurologically impaired populations. TMS is used extensively to study motor control and the response to neurorehabilitation of the upper extremities. However, TMS has been less utilized in the study of lower extremity postural and walking-specific motor control. The limited use and the additional methodological challenges of lower extremity TMS assessments have contributed to the lack of consistency in lower extremity TMS procedures within the literature. Inspired by the decreased ability to record lower extremity TMS motor evoked potentials (MEP), this methodological report details steps to enable post-stroke TMS assessments in a standing posture. The standing posture allows for the activation of the neuromuscular system, reflecting a state more akin to the system's state during postural and walking tasks. Using dual-top force plates, we instructed participants to equally distribute their weight between their paretic and non-paretic legs. Visual feedback of the participants' weight distribution was provided. Using image guidance software, we delivered single TMS pulses via a double-cone coil to the participants' lesioned and non-lesioned hemispheres and measured the corticomotor response of the paretic and non-paretic tibialis anterior and soleus muscles. Performing assessments in the standing position increased the TMS response rate and allowed for the use of the lower stimulation intensities compared to the standard sitting/resting position. Utilization of this TMS protocol can provide a common approach to assess the lower extremity corticomotor response post-stroke when the neurorehabilitation of postural and gait impairments are of interest.

Transcranial magnetic stimulation (TMS) is a technique used to probe and measure cortico-motor responses of the nervous system. However, lower extremity (LE) specific methodology has been slow to develop. In this retrospective analysis, we investigated what motor evoked potential metric, amplitude (MEP amp ) or latency (MEP lat ), best distinguished the motor-cortical target, i.e. hotspot, of the tibialis anterior and soleus post-stroke. Twenty-three participants with stroke were included in this investigation. Neuronavigation was used to map hotspots, derived via MEP amp and MEP lat , over a 3cm × 5cm grid. Distances between points with the greatest response within a session and between days were compared. Both criterion, amplitude and latency, provided poor identification of locations between trials within a session, and between multiple visits. Identified hotspots were similar only 15 % and 8% of the time between two assessments within the same session, for amplitude and latency respectively. However, MEP amp was more consistent in identifying hotspots, evidenced by locations being less spatially distant from each other (Amplitude: 1.4 cm (SD 0.10) Latency: 1.7 (SD 1.04), P = 0.008) within a session and between days (Amplitude: 1.3 cm (SD 0.95), Latency 1.9 cm (SD 1.14), P = 0.004). While more work is needed to develop LE specific methodology for TMS, especially as it applies to investigating gait impairments, MEP amp appears to be a more consistent criterion for hotspot identification when compared to MEP lat . It is recommended that future works continue to use MEP amp when identifying tibialis anterior and soleus hotspots using neuronavigation., (Published by Elsevier B.V.)

Background : In this pilot study, we examined the effects of ipsilesional high-frequency rTMS (iHF-rTMS) and contralesional low-frequency rTMS (cLF-rTMS) applied via a double-cone coil on neurophysiological and gait variables in patients with chronic stroke. Objective/Hypothesis : To determine the group and individual level effects of two types of stimulation to better individualize neuromodulation for rehabilitation. Methods : Using a randomized, within-subject, double-blind, sham-controlled trial with 14 chronic stroke participants iHF-rTMS and cLF-rTMS were applied via a double-cone coil to the tibialis anterior cortical representation. Neurophysiological and gait variables were compared pre-post rTMS. Results : A small effect of cLF-rTMS indicated increased MEP amplitudes (Cohen's D; cLF-rTMS, d = -0.30). Group-level analysis via RMANOVA showed no significant group effects of stimulation ( P > 0.099). However, secondary analyses of individual data showed a high degree of response variability to rTMS. Individual percent changes in resting motor threshold and normalized MEP latency correlated with changes in gait propulsive forces and walking speed (iHF-rTMS, nLAT:Pp, R = 0.632 P = 0.015; cLF-rTMS, rMT:SSWS, R = -0.557, P = 0.039; rMT:Pp, R = 0.718, P = 0.004). Conclusions : Changes in propulsive forces and walking speed were seen in some individuals that showed neurophysiological changes in response to rTMS. The neurological consequences of stroke are heterogeneous making a "one type fits all" approach to neuromodulation for rehabilitation unlikely. This pilot study suggests that an individual's unique response to rTMS should be considered before the application/selection of neuromodulatory therapies. Before neuromodulatory therapies can be incorporated into standard clinical practice, additional work is needed to identify biomarkers of response and how best to prescribe neuromodulation for rehabilitation for post-stroke gait., (Copyright © 2020 Kindred, Wonsetler, Charalambous, Srivastava, Marebwa, Bonilha, Kautz and Bowden.)

Advances in medical diagnosis and treatment have facilitated the emergence of precision medicine. In contrast, locomotor rehabilitation for individuals with acquired neuromotor injuries remains limited by the dearth of (i) diagnostic approaches that can identify the specific neuromuscular, biomechanical, and clinical deficits underlying impaired locomotion and (ii) evidence-based, targeted treatments. In particular, impaired propulsion by the paretic limb is a major contributor to walking-related disability after stroke; however, few interventions have been able to target deficits in propulsion effectively and in a manner that reduces walking disability. Indeed, the weakness and impaired control that is characteristic of post-stroke hemiparesis leads to heterogeneous deficits that impair paretic propulsion and contribute to a slow, metabolically-expensive, and unstable gait. Current rehabilitation paradigms emphasize the rapid attainment of walking independence, not the restoration of normal propulsion function. Although walking independence is an important goal for stroke survivors, independence achieved via compensatory strategies may prevent the recovery of propulsion needed for the fast, economical, and stable gait that is characteristic of healthy bipedal locomotion. We posit that post-stroke rehabilitation should aim to promote independent walking, in part, through the acquisition of enhanced propulsion. In this expert review, we present the biomechanical and functional consequences of post-stroke propulsion deficits, review advances in our understanding of the nature of post-stroke propulsion impairment, and discuss emerging diagnostic and treatment approaches that have the potential to facilitate new rehabilitation paradigms targeting propulsion restoration.

Objective: The purpose of this study was to describe the process and cost of delivering a physical therapist-guided synchronous telehealth exercise program appropriate for older adults with functional limitations. Such programs may help alleviate some of the detrimental impacts of social distancing and quarantine on older adults at-risk of decline., Methods: Data were derived from the feasibility arm of a parent study, which piloted the telehealth program for 36 sessions with 1 participant. The steps involved in each phase (ie, development, delivery) were documented, along with participant and program provider considerations for each step. Time-driven activity-based costing was used to track all costs over the course of the study. Costs were categorized as program development or delivery and estimated per session and per participant., Results: A list of the steps and the participant and provider considerations involved in developing and delivering a synchronous telehealth exercise program for older adults with functional impairments was developed. Resources used, fixed and variable costs, per-session cost estimates, and total cost per person were reported. Two potential measures of the "value proposition" of this type of intervention were also reported. Per-session cost of $158 appeared to be a feasible business case, especially if the physical therapist to trained assistant personnel mix could be improved., Conclusions: The findings provide insight into the process and costs of developing and delivering telehealth exercise programs for older adults with functional impairments. The information presented may provide a "blue print" for developing and implementing new telehealth programs or for transitioning in-person services to telehealth delivery during periods of social distancing and quarantine., Impact: As movement experts, physical therapists are uniquely positioned to play an important role in the current COVID-19 pandemic and to help individuals who are at risk of functional decline during periods of social distancing and quarantine. Lessons learned from this study's experience can provide guidance on the process and cost of developing and delivering a telehealth exercise program for older adults with functional impairments. The findings also can inform new telehealth programs, as well as assist in transitioning in-person care to a telehealth format in response to the COVID-19 pandemic., (© The Author(s) 2020. Published by Oxford University Press on behalf of American Physical Therapy Association. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: The objective of this study was to determine the feasibility of a rehabilitation approach focusing on cardiovascular, strength, and gait training intensity in the inpatient rehabilitation setting after a new onset of stroke. We additionally aimed to determine the efficacy of this intensity-based program on rehabilitation outcomes compared with usual care., Design: Participants were pseudo-randomized to an intensity-based program focusing on gait, cardiovascular, and strength training or to usual care. Outcomes included FIM, 10-meter walk, 2-minute walk, timed Up and Go test, 5-time sit-to-stand test, and Tinetti balance assessment., Intervention: The intervention consisted of 6 20-minute sessions per week dedicated to intensity of activity: 2 each for walking, cardiovascular training, and strength training., Participants: Patients (N=49) with new onset stroke admitted to inpatient rehabilitation over the course of 1 year., Setting: Four inpatient rehabilitation facilities with comprehensive neurologic rehabilitation teams., Results: Thirty-five individuals (16 intervention, 19 controls) completed all testing. Subject compliance to the intensity intervention demonstrated completion of approximately half the prescribed sessions. All outcomes improved significantly from admission to discharge, and a significant interaction between treatment group and time was observed for the 2-minute walk and the Tinetti balance assessment. The 2-minute walk, Tinetti balance assessment, 10-meter walk, and FIM demonstrated between-group effect sizes greater than 0.60 in favor of the intervention group., Conclusions: The intensity-based protocol was safe, and several measures demonstrated efficacy when compared with usual care. Results may have been limited by poor program compliance, showing a need to identify and ameliorate obstacles to integration of comprehensive intensity-based programs addressing endurance, strength, and gait training. Applying physiological principles of exercise to acute stroke rehabilitation demonstrates great promise for improving independent physical function., (© 2020 The Authors.)

Background: Gait propulsion is often altered following a stroke, with clear effects on anterior progression. Changes in the pattern of propulsion could potentially also influence swing phase mechanics. The purpose of the present study was to investigate whether post-stroke variability in paretic propulsion magnitude or timing influence paretic swing phase kinematics., Methods: 29 chronic stroke survivors participated in this study, walking on an instrumented treadmill at their self-selected and fastest-comfortable speeds. For each participant, we calculated several propulsion-related metrics derived from anteroposterior ground reaction force or from center of mass power, as well as knee flexion angle and circumduction displacement during the swing phase. We performed a series of linear mixed model analyses to determine whether the propulsion metrics for the paretic leg were related to paretic swing phase mechanics., Findings: A subset of the stroke survivors exhibited unusual braking forces late in the paretic stance phase, when strong propulsion typically occurs among uninjured controls. Beyond the effects of walking speed or walking condition, these braking forces were significantly linked with altered paretic swing phase mechanics. Specifically, large braking impulses were associated with reduced paretic knee flexion (p = 0.039) and increased paretic circumduction (p = 0.023)., Interpretation: The present results suggest that braking forces late in stance are particularly indicative of deficits in the production of typical swing phase kinematics. This relationship suggests that therapies designed to address altered swing kinematics should also consider altered force generation in late stance, as these behaviors appear to be coupled., Competing Interests: Declaration of competing interest The authors have no competing interests to declare., (Published by Elsevier Ltd.)

Slow walking speed and lack of balance control are common impairments post-stroke. While locomotor training often improves walking speed, its influence on dynamic balance is unclear. The goal of this study was to assess the influence of a locomotor training program on dynamic balance in individuals post-stroke during steady-state walking and determine if improvements in walking speed are associated with improved balance control. Kinematic and kinetic data were collected pre- and post-training from seventeen participants who completed a 12-week locomotor training program. Dynamic balance was quantified biomechanically (peak-to-peak range of frontal plane whole-body angular-momentum) and clinically (Berg-Balance-Scale and Dynamic-Gait-Index). To understand the underlying biomechanical mechanisms associated with changes in angular-momentum, foot placement and ground-reaction-forces were quantified. As a group, biomechanical assessments of dynamic balance did not reveal any improvements after locomotor training. However, improved dynamic balance post-training, observed in a sub-group of 10 participants (i.e., Responders), was associated with a narrowed paretic foot placement and higher paretic leg vertical ground-reaction-force impulse during late stance. Dynamic balance was not improved post-training in the remaining seven participants (i.e., Non-responders), who did not alter their foot placement and had an increased reliance on their nonparetic leg during weight-bearing. As a group, increased walking speed was not correlated with improved dynamic balance. However, a higher pre-training walking speed was associated with higher gains in dynamic balance post-training. These findings highlight the importance of the paretic leg weight bearing and mediolateral foot placement in improving frontal plane dynamic balance post-stroke., (Copyright © 2019. Published by Elsevier Ltd.)

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique used to modulate cortical activity. However, measured effects on clinically relevant assessments have been inconsistent, possibly due to the non-focal dispersion of current from traditional two electrode configurations. High-definition (HD)-tDCS uses a small array of electrodes ( N = 5) to improve targeted current delivery. The purpose of this study was to determine the effects of a single session of anodal and cathodal HD-tDCS on gait kinematics and kinetics and the corticomotor response to transcranial magnetic stimulation (TMS) in individuals post-stroke. We hypothesized that ipsilesional anodal stimulation would increase the corticomotor response to TMS leading to beneficial changes in gait. Eighteen participants post-stroke (average age: 64.8 years, SD : 12.5; average months post-stroke: 54, SD : 42; average lower extremity Fugl-Meyer score: 26, SD : 6) underwent biomechanical and corticomotor response testing on three separate occasions prior to and after HD-tDCS stimulation. In a randomized order, anodal, cathodal, and sham HD-tDCS were applied to the ipsilesional motor cortex for 20 min while participants pedaled on a recumbent cycle ergometer. Gait kinetic and kinematic data were collected while walking on an instrumented split-belt treadmill with motion capture. The corticomotor response of the paretic and non-paretic tibialis anterior (TA) muscles were measured using neuronavigated TMS. Repeated measures ANOVAs using within-subject factors of time point (pre, post) and stimulation type (sham, anodal, cathodal) were used to compare effects of HD-tDCS stimulation on measured variables. HD-tDCS had no effect on over ground walking speed ( P > 0.41), or kinematic variables ( P > 0.54). The corticomotor responses of the TA muscles were also unaffected by HD-tDCS (resting motor threshold, P = 0.15; motor evoked potential (MEP) amplitude, P = 0.25; MEP normalized latency, P = 0.66). A single session of anodal or cathodal HD-tDCS delivered to a standardized ipsilesional area of the motor cortex does not appear to alter gait kinematics or corticomotor response post-stroke. Repeated sessions and individualized delivery of HD-tDCS may be required to induce beneficial plastic effects. Contralesional stimulation should also be investigated due to the altered interactions between the cerebral hemispheres post-stroke.

Distal leg muscles receive neural input from motor cortical areas via the corticospinal tract, which is one of the main motor descending pathway in humans and can be assessed using transcranial magnetic stimulation (TMS). Given the role of distal leg muscles in upright postural and dynamic tasks, such as walking, a growing research interest in the assessment and modulation of the corticospinal tracts relative to the function of these muscles has emerged in the last decade. However, methodological parameters used in previous work have varied across studies making the interpretation of results from cross-sectional and longitudinal studies less robust. Therefore, use of a standardized TMS protocol specific to the assessment of leg muscles' corticomotor response (CMR) will allow for direct comparison of results across studies and cohorts. The objective of this paper is to present a protocol that provides the flexibility to simultaneously assess the bilateral CMR of two main ankle antagonistic muscles, the tibialis anterior and soleus, using single pulse TMS with a neuronavigation system. The present protocol is applicable while the examined muscle is either fully relaxed or isometrically contracted at a defined percentage of maximum isometric voluntary contraction. Using each subject's structural MRI with the neuronavigation system ensures accurate and precise positioning of the coil over the leg cortical representations during assessment. Given the inconsistency in CMR derived measures, this protocol also describes a standardized calculation of these measures using automated algorithms. Though this protocol is not conducted during upright postural or dynamic tasks, it can be used to assess bilaterally any pair of leg muscles, either antagonistic or synergistic, in both neurologically intact and impaired subjects.

Background: Although walking speed is the most common measure of gait performance post-stroke, improved walking speed following rehabilitation does not always indicate the recovery of paretic limb function. Over the last decade, the measure paretic propulsion (Pp, defined as the propulsive impulse generated by the paretic leg divided by the sum of the propulsive impulses of both legs) has been established as a measure of paretic limb output and recently targeted in post-stroke rehabilitation paradigms. However, the literature lacks a detailed synthesis of how paretic propulsion, walking speed, and other biomechanical and neuromuscular measures collectively relate to post-stroke walking performance and motor recovery., Objective: The aim of this review was to assess factors associated with the ability to generate Pp and identify rehabilitation targets aimed at improving Pp and paretic limb function., Methods: Relevant literature was collected in which paretic propulsion was used to quantify and assess propulsion symmetry and function in hemiparetic gait., Results: Paretic leg extension during terminal stance is strongly associated with Pp. Both paretic leg extension and propulsion are related to step length asymmetry, revealing an interaction between spatiotemporal, kinematic and kinetic metrics that underlies hemiparetic walking performance. The importance of plantarflexor function in producing propulsion is highlighted by the association of an independent plantarflexor excitation module with increased Pp. Furthermore, the literature suggests that although current rehabilitation techniques can improve Pp, these improvements depend on the patient's baseline plantarflexor function., Significance: Pp provides a quantitative measure of propulsion symmetry and should be a primary target of post-stroke gait rehabilitation. The current literature suggests rehabilitation techniques that target both plantarflexor function and leg extension may restore paretic limb function and improve gait asymmetries in individuals post stroke., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Stroke is the leading cause of long-term disability and individuals post-stroke often experience impaired walking ability. The plantarflexor (PF) muscles are critical to walking through their contributions to the ground reaction forces and body segment energetics. Previous studies have shown muscle activity during walking can be grouped into co-excited muscle sets, or modules. Improper co-activation, or merging of modules, is a common impairment in individuals post-stroke. The purpose of this study was to determine the influence of merged PF modules on walking performance in individuals post stroke by examining balance control, body support and propulsion, and walking symmetry. Muscle modules were identified using non-negative matrix factorization to classify subjects as having an independent or merged PF module. The merged group had decreased balance control with a significantly higher frontal plane whole-body angular momentum than both the independent and control groups, while the independent and control groups were not significantly different. The merged group also had higher paretic braking and nonparetic propulsion than both the independent and control groups. These results remained when comparisons were limited to subjects who had the same number of modules, indicating this was not a general effect due to subjects with merged PF having fewer modules. It is likely that a merged PF module is indicative of general PF dysfunction even when some activation occurs at the appropriate time. These results suggest an independent PF module is critical to walking performance, and thus obtaining an independent PF module should be a crucial aim of stroke rehabilitation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The investigation of the corticomotor connectivity (CMC) to leg muscles is an emerging research area, and establishing reliability of measures is critical. This study examined the measurement reliability and the differences between bilateral soleus (SOL) and tibialis anterior (TA) CMC in 21 neurologically intact adults. Using single pulse transcranial magnetic stimulation (TMS), each muscle's CMC was assessed twice (7 ± 2 days apart) during rest and active conditions. CMC was quantified using a standardized battery of eight measures (4/condition): motor threshold during resting (RMT), motor evoked potential amplitude and latency (raw and normalized to height) in both conditions, contralateral silent period (CSP) during active. Using two reliability metrics (intraclass correlation coefficient and coefficient of variation of method error; good reliability: ≥0.75 and ≤15, respectively) and repeated-measures ANOVA, we investigated the reliability and Muscle X Body Side interaction. For both muscles, RMT, resting raw and normalized latencies, and active raw latency demonstrated good reliability, while CSP had good reliability only for TA. Amplitude did not demonstrate good reliability for both muscles. SOL CMC was significantly different from TA CMC for all measures but CSP; body side had no significant effect. Therefore, only certain measures may reliably quantify SOL and TA CMC while different CMC (except CSP) between SOL and TA suggests dissimilar corticospinal drive to each muscle regardless of the side., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Kinematic and kinetic outcome measures are tightly linked in walking. Although altering motor output is a major goal of gait rehabilitation, little is understood regarding the relationship between altering a single kinematic variable and kinetic outcome changes. We designed a strategy to isolate hip extension alterations during walking on a treadmill to assess the change in kinetic outcomes. Ten healthy individuals walked on an instrumented split-belt treadmill with motion capture to calculate hip extension and kinetic outcomes at the following five different randomized cadences: self-selected cadence, self-selected ± 10%, and self-selected ± 20%. The treadmill speed was held constant at the individual's self-selected walking speed, forcing cadence changes to result in successful alterations to hip extension, varying 8.3 degrees from the self-selected -20% to +20% cadence conditions. Kinetic outcomes demonstrated similar alterations. Hip extension changes at each cadence significantly correlated with kinetic changes in propulsive impulse (r = 0.852, P < 0.001), peak ankle power (r = 0.473, P = 0.002), and ankle plantarflexion work (r = 0.762, P < 0.001). These results demonstrate that kinetic outcomes are highly alterable in response to a kinematic gait change. This clinically relevant finding highlights the potential to improve motor output in individuals during rehabilitation by altering gait patterns to achieve more optimal limb positions.

Background: Lower extremity muscle weakness is a primary contributor to post-stroke dysfunction. Resistance training is an effective treatment for hemiparetic weakness and improves walking performance. Post-stroke subject characteristics that do or do not improve walking speed following resistance training are unknown., Objective: The purpose of this paper was to describe baseline characteristics, as well as responses to training, associated with achieving a minimal clinically important difference (MCID) in walking speed (≥0.16 m/s) following Post-stroke Optimization of Walking Using Explosive Resistance (POWER) training., Methods: Seventeen participants completed 24 sessions of POWER training, which included intensive progressive leg presses, jump training, calf raises, sit-to-stands, step-ups, and over ground fast walking. Outcomes included SSWS, FCWS, DGI, FMA-LE, 6-MWT, paretic knee power, non-paretic knee power, and paretic step ratio., Results: Specific to those who reached MCID in SSWS (e.g. "responders"), significant improvements in SSWS, FCWS, 6-MWT, paretic knee power, and non-paretic knee power was realized. Paretic knee power and non-paretic knee power significantly improved in those who did not achieve MCID for gait speed (e.g. "non-responders")., Conclusion: The potential for POWER training to enhance general locomotor function was confirmed. Baseline paretic knee strength/power may be an important factor in how an individual responds to this style of training. The lack of change within the non-responders emphasizes the contribution of factors other than lower extremity muscle power improvement to locomotor dysfunction.

Background: In walking rehabilitation trials, self-selected walking speed (SSWS) has emerged as the dominant outcome measure to assess walking ability. However, this measure cannot differentiate between recovery of impaired movement and compensation strategies. Spatiotemporal variables and asymmetry ratios are frequently used to quantify gait deviations and are hypothesized markers of recovery., Objectives: The purpose of this review is to investigate spatiotemporal variables and asymmetry ratios as mechanistic recovery measures in physical therapy intervention studies post-stroke., Methods: A systematic literature search was performed to identify physical therapy intervention studies with a statistically significant change in SSWS post intervention and concurrently collected spatiotemporal variables. Methodological quality was assessed using the Cochrane Collaboration's tool. Walking speed, spatiotemporal, and intervention data were extracted., Results: 46 studies met the inclusion criteria, 41 of which reported raw spatiotemporal measures and 19 reported asymmetry ratio calculations. Study interventions included: aerobic training (n = 2), functional electrical stimulation (n = 5), hippotherapy (n = 2), motor dual task training (n = 2), multidimensional rehabilitation (n = 4), robotics (n = 4), sensory stimulation training (n = 8), strength/resistance training (n = 4), task specific locomotor rehabilitation (n = 9), and visually guided training (n = 6)., Conclusions: Spatiotemporal variables help describe gait deviations, but scale to speed, so consequently, may not be an independent factor in describing functional recovery and gains. Therefore, these variables are limited in explaining mechanistic changes involved in improving gait speed. Use of asymmetry measures provides additional information regarding the coordinative requirements for gait and can potentially indicate recovery. Additional laboratory-based mechanistic measures may be required to truly understand how walking speed improves.

Background: Regaining locomotor ability is a primary goal in stroke rehabilitation and is most commonly measured using changes in self-selected walking speed. However, walking speed cannot identify the mechanisms by which an individual recovers. Laboratory-based mechanistic measures such as exercise capacity, muscle activation, force production, and movement analysis variables may better explain neurologic recovery., Objectives: The objectives of this systematic review are to examine changes in mechanistic gait outcomes and describe motor recovery as quantified by changes in laboratory-based mechanistic variables in rehabilitation trials., Methods: Following a systematic literature search (in PubMed, Ovid, and CINAHL), we included rehabilitation trials with a statistically significant change in self-selected walking speed post-intervention that concurrently collected mechanistic variables. Methodological quality was assessed using Cochrane Collaboration's tool. Walking speed changes, mechanistic variables, and intervention data were extracted., Results: Twenty-five studies met the inclusion criteria and examined: cardiorespiratory function (n = 5), muscle activation (n = 5), force production (n = 11), and movement analysis (n = 10). Interventions included: aerobic training, functional electrical stimulation, multidimensional rehabilitation, robotics, sensory stimulation training, strength/resistance training, task-specific locomotor rehabilitation, and visually-guided training., Conclusions: Following this review, no set of outcome measures to mechanistically explain changes observed in walking speed were identified. Nor is there a theoretical basis to drive the complicated selection of outcome measures, as many of these outcomes are not independent of walking speed. Since rehabilitation literature is yet to support a causal, mechanistic link for functional gains post-stroke, a systematic, multimodal approach to stroke rehabilitation will be necessary in doing so.

Objective: To investigate the dimensionality and item-difficulty hierarchy of the Fugl-Meyer Assessment of the lower extremity (FMA-LE)., Design: Secondary analyses of data pooled from 4 existing datasets: a phase III randomized controlled trial investigating the effectiveness of body weight support and a treadmill for rehabilitation of walking poststroke, and 3 cross-sectional studies investigating the link between impaired motor performance poststroke and walking., Setting: University research centers and rehabilitation centers., Participants: A pooled sample of individuals with a stroke (N=535, men=313; mean age ± SD, 61.91±12.42y)., Interventions: Not applicable., Main Outcome Measures: Confirmatory factor analyses (CFA) and Rasch residual principal component analysis (PCA) investigated the dimensionality of the FMA-LE. The Rasch analysis rating scale model investigated item-difficulty hierarchy of the FMA-LE., Results: The CFA showed adequate fit of a 3-factor model, with 2 out of 3 indices (CFA=.95; Tucker-Lewis Index=.94; root mean square error of approximation=.124) showing good model fit. Rasch PCA showed that removal of the reflex and coordination items explained 90.8% of variance in the data, suggesting that the abnormal synergy items contributed to the measurement of a unidimensional construct. However, rating scale model results revealed deviations in the item-difficulty hierarchy of the unidimensional abnormal synergy items from the originally proposed stepwise sequence of motor recovery., Conclusions: Our findings suggest that the FMA-LE might represent a multidimensional construct, challenging the use of a total score of the FMA-LE to predict lower extremity motor recovery. Removal of the misfit items resulted in creation of a unidimensional scale composed of the abnormal synergy items. However, this unidimensional scale deviates from the originally proposed hierarchical ordering., Competing Interests: There is no conflict of interest associated with this study., (Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Mediolateral balance control during walking is a challenging task in post-stroke hemiparetic individuals. To detect and treat dynamic balance disorders, it is important to assess balance using reliable methods. The Berg Balance Scale (BBS), Dynamic Gait Index (DGI), margin-of-stability (MoS), and peak-to-peak range of angular-momentum (H) are some of the most commonly used measures to assess dynamic balance and fall risk in clinical and laboratory settings. However, it is not clear if these measures lead to similar conclusions. Thus, the purpose of this study was to assess dynamic balance in post-stroke hemiparetic individuals using BBS, DGI, MoS and the range of H and determine if these measure are correlated. BBS and DGI were collected from 19 individuals post-stroke. Additionally, kinematic and kinetic data were collected while the same individuals walked at their self-selected speed. MoS and the range of H were calculated in the mediolateral direction for each participant. Correlation analyses revealed moderate associations between all measures. Overall, a higher range of angular-momentum was associated with a higher MoS, wider step width and lower BBS and DGI scores, indicating poor balance control. Further, only the MoS from the paretic foot placement, but not the nonparetic foot, correlated with the other balance measures. Although moderate correlations existed between all the balance measures, these findings do not necessarily advocate the use of a single measure as each test may assess different constructs of dynamic balance. These findings have important implications for the use and interpretation of dynamic balance assessments., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background. Approximately 35,000 strokes occur annually in adults below the age of 40, and there is disappointingly little data describing their responses to rehabilitation. The purpose of this analysis was to determine the effects of Poststroke Optimization of Walking using Explosive Resistance (POWER) training in young (<40 years) and older (>60 years) adults and to describe relationships between training-induced improvements in muscular and locomotor function. Methods. Data was analyzed from 16 individuals with chronic stroke who participated in 24 sessions of POWER training. Outcomes included muscle power generation, self-selected walking speed (SSWS), 6-minute walk test, Fugl-Meyer motor assessment, Berg Balance Scale, and Dynamic Gait Index. Results. There were no significant differences between groups at baseline. Within-group comparisons revealed significant improvements in paretic and nonparetic knee extensor muscle power generation in both groups. Additionally, young participants significantly improved SSWS. Improvements in SSWS were more strongly associated with improvements in power generation on both sides in young versus older participants. Conclusions. Younger adults after stroke seem to preferentially benefit from POWER training, particularly when increasing gait speed is a rehabilitation goal. Future research should aim to further understand age-related differences in response to training to provide optimal treatments for all individuals following stroke.

Despite the plethora of human neurophysiological research, the bilateral involvement of the leg motor cortical areas and their interhemispheric interaction during both normal and impaired human walking is poorly understood. Using transcranial magnetic stimulation (TMS), we have expanded our understanding of the role upper-extremity motor cortical areas play in normal movements and how stroke alters this role, and probed the efficacy of interventions to improve post-stroke arm function. However, similar investigations of the legs have lagged behind, in part, due to the anatomical difficulty in using TMS to stimulate the leg motor cortical areas. Additionally, leg movements are predominately bilaterally controlled and require interlimb coordination that may involve both hemispheres. The sensitive, but invasive, tools used in animal models of locomotion hold great potential for increasing our understanding of the bihemispheric motor cortical control of walking. In this review, we discuss 3 themes associated with the bihemispheric motor cortical control of walking after stroke: (a) what is known about the role of the bihemispheric motor cortical control in healthy and poststroke leg movements, (b) how the neural remodeling of the contralesional hemisphere can affect walking recovery after a stroke, and (c) what is the effect of behavioral rehabilitation training of walking on the neural remodeling of the motor cortical areas bilaterally. For each theme, we discuss how rodent models can enhance the present knowledge on human walking by testing hypotheses that cannot be investigated in humans, and how these findings can then be back-translated into the neurorehabilitation of poststroke walking., (© The Author(s) 2015.)

Background: Lower extremity strength has been reported to relate to walking ability, however, the relationship between voluntary lower extremity muscle function as measured by isokinetic dynamometry and walking have not been thoroughly examined in individuals with incomplete spinal cord injury (iSCI)., Objective: To determine the extent to which measures of maximal voluntary isometric contraction (MVIC) and rate of torque development (RTD) in the knee extensor (KE) and plantar flexor (PF) muscle groups correlate with self-selected overground walking speed and spatiotemporal characteristics of walking., Methods: Twenty-two subjects with chronic (>6 months) iSCI participated in a cross-sectional study. Values for MVIC and RTD in the KE and PF muscle groups were determined by isokinetic dynamometry. Walking speed and spatiotemporal characteristics of walking were measured during overground walking., Results: MVIC in the KE and PF muscle groups correlated significantly with walking speed. RTD was significantly correlated with walking speed in both muscle groups, the more-involved PF muscle group showing the strongest correlation with walking speed (r = 0.728). RTD in the KE and PF muscle groups of the more-involved limb was significantly correlated with single support time of the more-involved limb., Conclusions: These data demonstrate that lower extremity strength is associated with walking ability after iSCI. Correlations for the muscle groups of the move-involved side were stronger compared to the less-involved limb. In addition, PF function is highlighted as a potential limiting factor to walking speed along with the importance of RTD.

Unlabelled: The ability to precisely quantify human movement within the laboratory setting provides researchers with data that comprehensively describe movement dysfunction in clinical cohorts. Furthermore, these data can be effectively utilized to identify potential underlying mechanisms as targets for therapeutic intervention. Although the utility of these methodologies is evidenced by the number of laboratories incorporating these techniques to understand clinical pathologies, the direct translation to clinical practice remains elusive and there exists an information gap between researchers studying these populations and the clinicians developing treatment for the individuals., Method: Recent technological advancements allow researchers and their clinician counterparts to measure certain elements of human movement outside of the laboratory. Specifically, the use of portable accelerometers allows for calculation of acceleration of the center of mass (COMa) during walking. COMa can be then be used to infer information about force generation by the individual during walking. This information may then be used by researchers to integrate with laboratory based results as well as by clinicians to partner with clinical findings, thus guiding clinical decision making as well as treatment design. The extent to which these types of measurement devices can be used to generate specific data describing human movement away from the lab is in the early stages of investigation, however, the potential for their use is something that could help advance research and patient care in the future., (Published by Elsevier B.V.)

Respiratory surfaces are exposed to billions of particulates and pathogens daily. A protective mucus barrier traps and eliminates them through mucociliary clearance (MCC). However, excessive mucus contributes to transient respiratory infections and to the pathogenesis of numerous respiratory diseases. MUC5AC and MUC5B are evolutionarily conserved genes that encode structurally related mucin glycoproteins, the principal macromolecules in airway mucus. Genetic variants are linked to diverse lung diseases, but specific roles for MUC5AC and MUC5B in MCC, and the lasting effects of their inhibition, are unknown. Here we show that mouse Muc5b (but not Muc5ac) is required for MCC, for controlling infections in the airways and middle ear, and for maintaining immune homeostasis in mouse lungs, whereas Muc5ac is dispensable. Muc5b deficiency caused materials to accumulate in upper and lower airways. This defect led to chronic infection by multiple bacterial species, including Staphylococcus aureus, and to inflammation that failed to resolve normally. Apoptotic macrophages accumulated, phagocytosis was impaired, and interleukin-23 (IL-23) production was reduced in Muc5b(-/-) mice. By contrast, in mice that transgenically overexpress Muc5b, macrophage functions improved. Existing dogma defines mucous phenotypes in asthma and chronic obstructive pulmonary disease (COPD) as driven by increased MUC5AC, with MUC5B levels either unaffected or increased in expectorated sputum. However, in many patients, MUC5B production at airway surfaces decreases by as much as 90%. By distinguishing a specific role for Muc5b in MCC, and by determining its impact on bacterial infections and inflammation in mice, our results provide a refined framework for designing targeted therapies to control mucin secretion and restore MCC.

Background: In the past several years, several randomized controlled trials (RCTs) have been reported regarding the efficacy of treadmill-based walking-specific rehabilitation programs, either individually (TT) or combined with body weight support (BWSTT), over control group therapies poststroke. No clear consensus exists as to whether treadmill-based interventions are superior in rehabilitating walking speed (WS) poststroke., Objective: To review published RCTs examining TT and BWSTT poststroke and describe the effects on improving and retaining WS., Methods: A systematic literature search in computerized databases was conducted to identify RCTs whose methodological quality was assessed with PEDro. Pre- and post-WS, change in WS, functional outcomes, and follow-up speed were extracted and calculated from each study. Additionally, statistical results of each study were examined, and the intragroup and intergroup effect sizes (ESintra and ESinter, respectively) were calculated., Results: All studies (8 TT; 7 BWSTT) met the inclusion criteria, and their methodological quality was generally good, with a mean PEDro score 6.9/10. Of the 15 studies, 8 studies (4 TT; 4 BWSTT) reported intragroup significant increases of WS, whereas only 4 (4 TT) found superiority of treadmill interventions. Nine studies demonstrated large ESintra (4 TT; 5 BWSTT), yet only 3 showed large ESinter (1 TT; 2 BWSTT). Four studies (2 TT and 2 BWSTT) reported retention of gains in WS, regardless of intervention., Conclusions: Treadmill-based interventions poststroke may increase and retain WS, but their universal superiority to other control group therapies has failed to be established.

Recent studies have suggested the biomechanical subtasks of walking can be produced by a reduced set of co-excited muscles or modules. Individuals post-stroke often exhibit poor inter-muscular coordination characterized by poor timing and merging of modules that are normally independent in healthy individuals. However, whether locomotor therapy can influence module composition and timing and whether these improvements lead to improved walking performance is unclear. The goal of this study was to examine the influence of a locomotor rehabilitation therapy on module composition and timing and post-stroke hemiparetic walking performance. Twenty-seven post-stroke hemiparetic subjects participated in a 12-week locomotor intervention incorporating treadmill training with body weight support and manual trainers accompanied by training overground walking. Electromyography (EMG), kinematic and ground reaction force data were collected from subjects both pre- and post-therapy and from 19 age-matched healthy controls walking on an instrumented treadmill at their self-selected speed. Non-negative matrix factorization was used to identify the module composition and timing from the EMG data. Module timing and composition, and various measures of walking performance were compared pre- and post-therapy. In subjects with four modules pre- and post-therapy, locomotor training resulted in improved timing of the ankle plantarflexor module and a more extended paretic leg angle that allowed the subjects to walk faster and with more symmetrical propulsion. In addition, subjects with three modules pre-therapy increased their number of modules and improved walking performance post-therapy. Thus, locomotor training has the potential to influence module composition and timing, which can lead to improvements walking performance., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Objectives: To identify the clinical measures associated with improved walking speed after locomotor rehabilitation in individuals poststroke and how those who respond with clinically meaningful changes in walking speed differ from those with smaller speed increases., Design: A single group pre-post intervention study. Participants were stratified on the basis of a walking speed change of greater than (responders) or less than (nonresponders) .16m/s. Paired sample t tests were run to assess changes in each group, and correlations were run between the change in each variable and change in walking speed., Setting: Outpatient interdisciplinary rehabilitation research center., Participants: Hemiparetic subjects (N=27) (17 left hemiparesis; 19 men; age: 58.74±12.97y; 22.70±16.38mo poststroke)., Intervention: A 12-week locomotor intervention incorporating training on a treadmill with body weight support and manual trainers accompanied by training overground walking., Main Outcome Measures: Measures of motor control, balance, functional walking ability, and endurance were collected at pre- and postintervention assessments., Results: Eighteen responders and 9 nonresponders differed by age (responders=63.6y, nonresponders=49.0y, P=.001) and the lower extremity Fugl-Meyer Assessment score (responders=24.7, nonresponders=19.9, P=.003). Responders demonstrated an average improvement of .27m/s in walking speed as well as significant gains in all variables except daily step activity and paretic step ratio. Conversely, nonresponders demonstrated statistically significant improvements only in walking speed and endurance. However, the walking speed increase of .10m/s was not clinically meaningful. Change in walking speed was negatively correlated with changes in motor control in the nonresponder group, implying that walking speed gains may have been accomplished via compensatory mechanisms., Conclusions: This study is a step toward discerning the underlying factors contributing to improved walking performance., (Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

The clinical trial is essential to testing efficacy and effectiveness of therapeutic interventions. Neurorehabilitation presents unique challenges in the execution of clinical trials due to the complexity of both human interface with complex interventions and clinical/research staff interaction. Attention to key elements, recruitment, retention, treatment fidelity, and control intervention selection, contributes to successful conduct of a trial. Alternatives to the randomized controlled trial and outcome measure selection are important considerations contributing to the merit of the trial. While clinical trial outcomes contribute to the scientific evidence, their true value and impact comes in the next step, translation to clinical practice and the improvement of patient outcomes and qualify of life. Translation of evidence into practice may best be achieved via partnerships of scientists, clinicians, and administrators resulting in a dynamic interface between science and practice, the laboratory, and the clinic., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Motor impairment, dysphagia, aphasia, and visual impairment are common disabling residual deficits experienced by stroke survivors. Recently, many novel rehabilitative modalities have been investigated for their potential to ameliorate such deficits and to improve functional outcomes. Noninvasive brain stimulation techniques, such as transcranial direct current stimulation (tDCS), have emerged as a promising tool to facilitate stroke recovery. tDCS can alter cortical excitability to induce brain plasticity by modulating the lesioned, contralesional, or bilateral hemispheres with various stimulation modalities. Along with peripheral therapies, tDCS can lead to subsequent sustained behavioral and clinical gains in patients with stroke. In this review, we summarize characteristics of tDCS (method of stimulation, safety profile, and mechanism) and its application in the treatment of various stroke-related deficits, and we highlight future directions for tDCS in this capacity.

Opinion Statement: Rehabilitation of walking after stroke has been investigated with a variety of interventions, which will be outlined in this review. To date, the majority of interventions have demonstrated a positive, but similar effect in the primary clinical outcome of self-selected walking speed. Consistent among the most successful interventions is a focus on the intensity of the intervention and the ability to progress rehabilitation in a structured fashion. Successful progression of rehabilitation of walking likely lies in the ability to combine interventions based on an understanding of contributing underlying deficits (eg, motor control, strength, cardiovascular endurance, and dynamic balance). Rehabilitation programs must account for the need to train dynamic balance for falls prevention. Lastly, clinicians and researchers need to measure the effects of rehabilitation on participation and health related quality of life.

Background: Body-weight supported treadmill training has been shown to be effective in improving walking speed in post-stroke hemiparetic subjects, and those that have shown improvements generally maintain them after the completion of rehabilitation. However, currently no biomechanical variables are known to be related to those who will either continue to improve or regress in their self-selected walking speed during the 6-month period following rehabilitation. The objective of this study was to identify those biomechanical variables that are associated with subjects who continue (or did not continue) to improve their self-selected walking speed following the completion of rehabilitation., Methods: Experimental kinematic and kinetic data were recorded from 18 hemiparetic subjects who participated in a 6-month follow-up study after completing a 12-week locomotor training program that included stepping on a treadmill with partial body weight support and manual assistance. Pearson correlation coefficients were used to determine which biomechanical variables evaluated during the post-training session were related to changes in self-selected walking speed from post-training to a 6-month follow-up session., Findings: Following the completion of rehabilitation, the majority of subjects increased or retained (i.e., did not change) their self-selected walking speed from post-training to the follow-up session. Post-training step length symmetry and daily step activity were positively related to walking speed improvements., Interpretation: Motor control deficits that lead to persistent step length asymmetry and low daily step activity at the end of rehabilitation are associated with poorer outcomes six months after completion of the program., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Antibodies that recognize microbial B lymphocyte superantigenic epitopes are produced constitutively with no requirement for adaptive immune maturation. We report cleavage of the Staphylococcus aureus virulence factor extracellular fibrinogen-binding protein (Efb) by catalytic antibodies produced with no exposure to the bacterium and reduction of the catalytic antibody activity following infection. IgG catalytic antibodies that specifically hydrolyzed Efb via a nucleophilic catalytic mechanism were found in the blood of healthy humans and aseptic mice free of S. aureus infection. IgG hydrolyzed peptide bonds on the C-terminal side of basic amino acids, including a bond located within the C3b-binding domain of Efb. Efb digested with the IgG lost its ability to bind C3b and inhibit complement-dependent antibody-mediated red blood cell lysis. In addition to catalysis, the IgG expressed saturable Efb binding activity. IgG from S. aureus-infected mice displayed reduced Efb cleaving activity and increased Efb binding activity compared with uninfected controls, suggesting differing effects of the infection on the antibody subsets responsible for the two activities. IgG from children hospitalized for S. aureus infection also displayed reduced Efb cleavage compared with healthy children. These data suggest a potential defense function for constitutively produced catalytic antibodies to a putative superantigenic site of Efb, but an adaptive catalytic response appears to be proscribed.