Stroke survivors' perceptions of participating in a high repetition arm training trial early after stroke.

PURPOSE: The study explored the acceptability of high repetition arm training as part of a randomised controlled trial, early after stroke, when fatigue levels and emotional strain are often high. MATERIALS AND METHODS: 36 sub-acute stroke survivors (61 years+/-15) attended for assessment sessions at 3, 6, and 12 weeks after stroke. Individuals were randomised to receive 6 high repetition arm training sessions between 3 and 6 weeks (intervention) or the control group. Semi-structured interviews were conducted at trial completion. Interview transcripts were analysed through framework analysis conducted independently by 2 researchers. RESULTS: Stroke survivors participated despite high levels of fatigue because they hoped for personal benefit or to potentially benefit future patients. Benefits reported from participation included physical improvements, psychological benefit, improved understanding of their condition as well as a feeling of hope and distraction. The arm training at three weeks after stroke, aiming for 420 movement repetitions was not considered to be too intensive or too early, and most individuals felt lucky to have been, or would have preferred to be in the early training group. CONCLUSION: High repetition arm training early after stroke was acceptable to participants. Study participation was generally viewed as a positive experience, suggesting that early intervention may not only be physically beneficial but also psychologically.Implications for rehabilitationStroke survivors report that high repetition arm training early after stroke is acceptable.Participation in rehabilitation research early after stroke provides stroke survivors with hope and meaning despite the high prevalence of fatigue.Complex information needs to be repeated and provided in a number of formats early after stroke.

Foot-placement accuracy during planned and reactive target stepping during walking in stroke survivors and healthy adults.

BACKGROUND: The high prevalence of falls due to trips and slips following stroke may signify difficulty adjusting foot-placement in response to the environment. However, little is known about under what circumstances foot-placement adjustment becomes difficult for stroke survivors (SS), making the design of targeted rehabilitation interventions to improve independent community mobility difficult. RESEARCH QUESTION: To investigate the effect of planned and reactive target-stepping on foot-placement accuracy in stroke survivors and young and older healthy adults? METHODS: Young (N = 11, 30 ± 6 years) and older (N = 10, 64 ± 8 years) healthy adults and SS (N = 11, 67 ± 9 years) walked, at preferred pace, on a force instrumented treadmill. Each participant walked to illuminated targets, visible two steps in advance (planned) or appearing at contralateral midstance (reactive). Foot-placement error (magnitude and bias) and number of missed targets were compared. RESULTS: All participants missed more reactive than planned targets (p = 0.05), and SS missed more targets than young (p < 0.001) and older (p = 0.001) adults. But no interaction showing SS missed more reactive targets than other groups was found. For all groups: reactive adaptations to steps in the antero-posterior plane resulted in lower error than planned adaptations (p = 0.027). Lengthening steps where undershot more than shortening (p < 0.001) by all groups. Reactive medio-lateral adaptations over all induced larger error (p = 0.029) than planned and changed the direction of bias (p = 0.018). SIGNIFICANCE: SS experience difficulty making all adjustments, they showed increased error in all conditions but less pronounced difference between planned and reactive stepping. SS may use a reactive control strategy for all adjustments, in contrast to healthy young adults who may plan foot-placement in advance. The likelihood of stroke survivors misplacing a step is large, with 9.8% targets missed; possibly leading to falls. Further investigation is needed to understand foot-placement control strategies used by SS and the role of planning in gait adaptability.

Evaluation of the Effects of Prescribing Gait Complexity Using Several Fluctuating Timing Imperatives.

Variability in the temporal structure of gait patterns, measured by "Fractal Index" (FI), is thought to represent abundancy of movement patterns facilitating adaptive control of walking. However we do not know how FI changes according to different walking rhythms or if this is repeatable, as needed to exploit the paradigm for rehabilitation. Fourteen healthy young adults synchronised heel contact to an auditory metronome twice each in four conditions (uncued, white noise, pink noise, and red noise) and three sessions. FI differed based on the walking condition while no effect of session was revealed. The results of this study suggest gait fractality changes systematically with different stimuli and can be consistently prescribed in a desired direction within a group of healthy young individuals.

How accuracy of foot-placement is affected by the size of the base of support and crutch support in stroke survivors and healthy adults.

BACKGROUND: The high prevalence of falls due to trips and slips following stroke may signify difficulty controlling balance and adjusting foot-placement in response to the environment. We know very little about how controlling foot-placement is affected by balance requirements and the effects of stroke. Therefore, in this study the research question is how foot-placement control is affected by balance support from crutches and reducing or enlarging the base of support. By understanding how foot-placement control and balance deficits following stroke interact, rehabilitation efforts can be more effectively targeted towards the cause of poor mobility. METHODS: Young (N=13, 30±6 years) and older (N=10, 64±8 years) healthy adults and stroke survivors (N=11, 67±9 years) walked to targets on an instrumented treadmill with or without crutch support for balance. Targets were randomized to either reduce or increase the base of support in the antero-posterior (AP) or medio-lateral (ML) direction. Mean and absolute foot-placement error were measured using motion analysis. These outcomes were compared using repeated measures ANCOVA with walking speed as a covariate. RESULTS: Overall, stroke survivors missed more targets (9.1±2.3%, p=0.001) than young (1.0±2.5%) and older (0.2±2.1%) healthy adults (p=0.001). However, there were no significant differences between groups in foot-placement error. Crutch support reduced both AP and ML foot-placement error (p=<0.001, AP 5.2±0.5cm unsupported, 4.1±0.4cm supported, ML 2.3±0.2cm unsupported, 1.9±0.2cm supported) for all participants. Interaction effects indicate crutch support reduced foot-placement error more when narrowing (unsupported 2.8±0.2cm, supported 1.8±0.2cm) than widening (unsupported 2.6±0.4cm, supported 2.4±0.4cm) steps (p<0.001), SIGNIFICANCE: Stroke survivors have greater difficulty accurately adjusting steps in response to the environment. Crutch support reduces foot-placement error for all steps, but particularly when narrowing foot-placement. These results provide support for the implication of walking aids, which support balance to improve ability to adjust footplacement in response to the environment.

Quantifying sit-to-stand and stand-to-sit transitions in free-living environments using the activPAL thigh-worn activity monitor.

PURPOSE: Standing up, sitting down and walking require considerable effort and coordination, which are crucial indicators to rehabilitation (e.g. stroke), and in older populations may indicate the onset of frailty and physical and cognitive decline. Currently, there are few reports robustly quantifying sit-to-stand and stand-to-sit transitions in free-living environments. The aim of this study was to identify and quantify these transitions using the peak velocity of sit-to-stand and stand-to-sit transitions to determine if these velocities were different in a healthy cohort and a mobility-impaired population. METHODS: Free-living sit-to-stand and stand-to-sit acceleration data were recorded from 21 healthy volunteers and 34 stroke survivors using activPAL3™ monitors over a one-week period. Thigh inclination velocity was calculated from these accelerometer data. Maximum velocities were compared between populations. RESULTS: A total of 10,299 and 11,392 sit-to-stand and stand-to-sit transitions were recorded in healthy volunteers and stroke survivors, respectively. Healthy volunteers had significantly higher overall mean peak velocities for both transitions compared with stroke survivors [70.7°/s ± 52.2 versus 44.2°/s ± 28.0 for sit-to-stand, P < 0.001 and 74.7°/s ± 51.8 versus 46.0°/s ± 31.9 for stand-to-sit; P < 0.001]. Mean peak velocity of transition was associated with increased variation in peak velocity across both groups. CONCLUSION: There were significant differences in the mean peak velocity of sit-to-stand and stand-to-sit transitions between the groups. Variation in an individual's mean peak velocity may be associated with the ability to perform these transitions. This method could be used to evaluate the effectiveness of interventions following injury such as stroke, as well as monitor decline in functional ability.

Gait adaptability.

Our activities of daily living inherently involve interacting with the physical environment. This interaction involves both reactive (feedback) and proactive (feedforward) gait adaptations. Reactive adaptations involve responses to mechanical perturbations and occur, for instance, when we stumble over a doorstep or slip on an icy spot on the pavement. Examples of proactive adaptations in response to visual stimuli include stepping over an obstacle, targeting precise foot placements when walking on rough terrain, stepping up to the pavement, or making a turn for going around a corner. These adaptations have to be implemented in our steady-state gait pattern, thus posing a challenge to center-of-mass control and maintenance of forward progression. Yet, despite the apparent complexity of adaptive bipedal walking, we commonly do this with remarkable ease. This chapter will provide a comprehensive overview of the behavioral strategies and control mechanisms that we apply for executing these common, yet complex, gait adaptations. In addition, how we use visual information for guiding proactive gait adaptations and path selection will be discussed. Finally, cognitive involvement during gait adaptations will also be addressed.

Validation of gait event detection by centre of pressure during target stepping in healthy and paretic gait.

BACKGROUND: Target-stepping paradigms are increasingly used to assess and train gait adaptability. Accurate gait-event detection (GED) is key to locating targets relative to the ongoing step cycle as well as measuring foot-placement error. In the current literature GED is either based on kinematics or centre of pressure (CoP), and both have been previously validated with young healthy individuals. However, CoP based GED has not been validated for stroke survivors who demonstrate altered CoP pattern. METHODS: Young healthy adults and individuals affected by stroke stepped to targets on a treadmill, while gait events were measured using three detection methods; verticies of CoP cyclograms, and two kinematic criteria, (1) vertical velocity and position and of the heel marker, (2) anterior velocity and position of the heel and toe marker, were used. The percentage of unmatched gait events was used to determine the success of the GED method. The difference between CoP and kinematic GED methods were tested with two one sample (two-tailed) t-tests against a reference value of zero. Differences between group and paretic and non-paretic leg were tested with a repeated measures ANOVA. RESULTS: The kinematic method based on vertical velocity only detected about 80% of foot contact events on the paretic side in stroke survivors while the method on anterior velocity was more successful in both young healthy adults as stroke survivors (3% young healthy and 7% stroke survivors unmatched). Both kinematic methods detected gait events significantly earlier than CoP GED (p < 0.001) except for foot contact in stroke survivors based on the vertical velocity. CONCLUSIONS: CoP GED may be more appropriate for gait analyses of SS than kinematic methods; even when walking and varying steps.

Functional electrical stimulation and ankle foot orthoses provide equivalent therapeutic effects on foot drop: A meta-analysis providing direction for future research.

OBJECTIVE: To compare the randomized controlled trial evidence for therapeutic effects on walking of functional electrical stimulation and ankle foot orthoses for foot drop caused by central nervous system conditions. DATA SOURCES: MEDLINE, CINAHL, Cochrane Central Register of Controlled Trials, REHABDATA, PEDro, NIHR Centre for Reviews and Dissemination, Scopus and clinicaltrials.gov. STUDY SELECTION: One reviewer screened titles/abstracts. Two independent reviewers then screened the full articles. DATA EXTRACTION: One reviewer extracted data, another screened for accuracy. Risk of bias was assessed by 2 independent reviewers using the Cochrane Risk of Bias Tool. DATA SYNTHESIS: Eight papers were eligible; 7 involving participants with stroke and 1 involving participants with cerebral palsy. Two papes reporting different measures from the same trial were grouped, resulting in 7 synthesized randomized controlled trials (n= 464). Meta-analysis of walking speed at final assessment (p = 0.46), for stroke participants (p = 0.54) and after 4-6 weeks' use (p = 0.49) showed equal improvement for both devices. CONCLUSION: Functional electrical stimulation and ankle foot orthoses have an equally positive therapeutic effect on walking speed in non-progressive central nervous system diagnoses. The current randomized controlled trial evidence base does not show whether this improvement translates into the user's own environment or reveal the mechanisms that achieve that change. Future studies should focus on measuring activity, muscle activity and gait kinematics. They should also report specific device details, capture sustained therapeutic effects and involve a variety of central nervous system diagnoses.

Functional electrical stimulation versus ankle foot orthoses for foot-drop: A meta-analysis of orthotic effects.

OBJECTIVE: To compare the effects on walking of functional electrical stimulation (FES) and ankle foot orthoses for foot-drop of central neurological origin, assessed in terms of unassisted walking behaviours compared with assisted walking following a period of use (combined-orthotic effects). DATA SOURCES: MEDLINE, AMED, CINAHL, Cochrane Central Register of Controlled Trials, Scopus, REHABDATA, PEDro, NIHR Centre for Reviews and Dissemination and clinicaltrials.gov, plus reference list, journal, author and citation searches. STUDY SELECTION: English language comparative randomized controlled trials (RCTs). DATA SYNTHESIS: Seven RCTs were eligible for inclusion. Two of these reported different results from the same trial and another 2 reported results from different follow-up periods and were therefore combined, resulting in 5 synthesized trials with 815 stroke participants. Meta-analyses of data from the final assessment in each study and 3 overlapping time-points showed comparable improvements in walking speed over 10 m (p = 0.04-0.79), functional exercise capacity (p = 0.10-0.31), timed up-and-go (p = 0.812 and p = 0.539) and perceived mobility (p = 0.80) for both interventions. CONCLUSION: Data suggest that, in contrast to assumptions that predict FES superiority, ankle foot orthoses have equally positive combined-orthotic effects as FES on key walking measures for foot-drop caused by stroke. However, further long-term, high-quality RCTs are required. These should focus on measuring the mechanisms-of-action; whether there is translation of improvements in impairment to function, plus detailed reporting of the devices used across diagnoses. Only then can robust clinical recommendations be made.

Feasibility and Preliminary Efficacy of Visual Cue Training to Improve Adaptability of Walking after Stroke: Multi-Centre, Single-Blind Randomised Control Pilot Trial.

OBJECTIVES: Given the importance of vision in the control of walking and evidence indicating varied practice of walking improves mobility outcomes, this study sought to examine the feasibility and preliminary efficacy of varied walking practice in response to visual cues, for the rehabilitation of walking following stroke. DESIGN: This 3 arm parallel, multi-centre, assessor blind, randomised control trial was conducted within outpatient neurorehabilitation services. PARTICIPANTS: Community dwelling stroke survivors with walking speed <0.8m/s, lower limb paresis and no severe visual impairments. INTERVENTION: Over-ground visual cue training (O-VCT), Treadmill based visual cue training (T-VCT), and Usual care (UC) delivered by physiotherapists twice weekly for 8 weeks. MAIN OUTCOME MEASURES: Participants were randomised using computer generated random permutated balanced blocks of randomly varying size. Recruitment, retention, adherence, adverse events and mobility and balance were measured before randomisation, post-intervention and at four weeks follow-up. RESULTS: Fifty-six participants participated (18 T-VCT, 19 O-VCT, 19 UC). Thirty-four completed treatment and follow-up assessments. Of the participants that completed, adherence was good with 16 treatments provided over (median of) 8.4, 7.5 and 9 weeks for T-VCT, O-VCT and UC respectively. No adverse events were reported. Post-treatment improvements in walking speed, symmetry, balance and functional mobility were seen in all treatment arms. CONCLUSIONS: Outpatient based treadmill and over-ground walking adaptability practice using visual cues are feasible and may improve mobility and balance. Future studies should continue a carefully phased approach using identified methods to improve retention. TRIAL REGISTRATION: Clinicaltrials.gov NCT01600391.

Visual cue training to improve walking and turning after stroke: a study protocol for a multi-centre, single blind randomised pilot trial.

BACKGROUND: Visual information comprises one of the most salient sources of information used to control walking and the dependence on vision to maintain dynamic stability increases following a stroke. We hypothesize, therefore, that rehabilitation efforts incorporating visual cues may be effective in triggering recovery and adaptability of gait following stroke. This feasibility trial aims to estimate probable recruitment rate, effect size, treatment adherence and response to gait training with visual cues in contrast to conventional overground walking practice following stroke. METHODS/DESIGN: A 3-arm, parallel group, multi-centre, single blind, randomised control feasibility trial will compare overground visual cue training (O-VCT), treadmill visual cue training (T-VCT), and usual care (UC). Participants (n = 60) will be randomly assigned to one of three treatments by a central randomisation centre using computer generated tables to allocate treatment groups. The research assessor will remain blind to allocation. Treatment, delivered by physiotherapists, will be twice weekly for 8 weeks at participating outpatient hospital sites for the O-VCT or UC and in a University setting for T-VCT participants.Individuals with gait impairment due to stroke, with restricted community ambulation (gait speed <0.8m/s), residual lower limb paresis and who are able to take part in repetitive walking practice involving visual cues (i.e., no severe visual impairments, able to walk with minimal assistance and no comorbid medical contraindications for walking practice) will be included.The primary outcomes concerning participant enrolment, recruitment, retention, and health and social care resource use data will be recorded over a recruitment period of 18 months. Secondary outcome measures will be undertaken before randomisation (baseline), after the eight-week intervention (outcome), and at three months (follow-up). Outcome measures will include gait speed and step length symmetry; time and steps taken to complete a 180° turn; assessment of gait adaptability (success rate in target stepping); timed up and go; Fugl-Meyer lower limb motor assessment; Berg balance scale; falls efficacy scale; SF-12; and functional ambulation category. DISCUSSION: Participation and compliance measured by treatment logs, accrual rate, attrition, and response variation will determine sample sizes for an early phase randomised controlled trial and indicate whether a definitive late phase efficacy trial is justified. TRIAL REGISTRATION: Clinicaltrials.gov, NCT01600391.

Interventions for coordination of walking following stroke: systematic review.

Impairments in gait coordination may be a factor in falls and mobility limitations after stroke. Therefore, rehabilitation targeting gait coordination may be an effective way to improve walking post-stroke. This review sought to examine current treatments that target impairments of gait coordination, the theoretical basis on which they are derived and the effects of such interventions. Few high quality RCTs with a low risk of bias specifically targeting and measuring restoration of coordinated gait were found. Consequently, we took a pragmatic approach to describing and quantifying the available evidence and included non-randomised study designs and limited the influence of heterogeneity in experimental design and control comparators by restricting meta-analyses to pre- and post-test comparisons of experimental interventions only. Results show that physiotherapy interventions significantly improved gait function and coordination. Interventions involving repetitive task-specific practice and/or auditory cueing appeared to be the most promising approaches to restore gait coordination. The fact that overall improvements in gait coordination coincided with increased walking speed lends support to the hypothesis that targeting gait coordination gait may be a way of improving overall walking ability post-stroke. However, establishing the mechanism for improved locomotor control requires a better understanding of the nature of both neuroplasticity and coordination deficits in functional tasks after stroke. Future research requires the measurement of impairment, activity and cortical activation in an effort to establish the mechanism by which functional gains are achieved.

Stroke-related differences in axial body segment coordination during preplanned and reactive changes in walking direction.

This study quantitatively describes differences between participants with hemiparetic stroke and age-matched healthy participants in axial body segment and gait kinematics during a direction change task. Participants were required to change walking direction by 45 degrees, either to their left or right, at the midpoint of a 6-m path. Participants were visually cued either at the start of the walk (pre-planned) or one stride before they reached the turn point (reactive). The sequence and inter-segmental timing of axial orientation onset was preserved in participants with stroke. Analysis of a subgroup of stroke survivors indicated that participants with lesions affecting the basal ganglia (BG) took significantly longer time than control participants to initiate the reorientation synergy when making turns to their non-paretic side. We hypothesize that these differences are a product of asymmetrical activity of dopaminergic pathways in the brain resulting from compromised BG function.