Rehabilitation clinicians' perspectives of reactive balance training.

PURPOSE: Reactive balance training (RBT) aims to improve reactive balance control. However, because RBT involves clients losing balance, clinicians may view that it is unsafe or not feasible for some clients. We aimed to explore how clinicians implement RBT to treat balance and mobility issues. MATERIALS AND METHODS: Physiotherapists and kinesiologists across Canada who reported that they include RBT in their practices were invited to complete telephone interviews about their experiences with RBT. Interviews were transcribed verbatim, and analysed using a deductive thematic analysis. RESULTS: Ten participants completed telephone interviews, which lasted between 30-60 min. Participants primarily worked in a hospital setting (inpatient rehabilitation (n = 3); outpatient rehabilitation (n = 2)), and were treated clients with neurological conditions (n = 5). Four main themes were identified: 1) there is variability in RBT approaches; 2) knowledge can be a barrier and facilitator to RBT; 3) reactive balance control is viewed as an advanced skill; and 4) RBT experience builds confidence. CONCLUSIONS: Our findings suggest a need for resources to make clinical implementation of RBT more feasible.Implications for rehabilitationTrust between the therapist and client improves self-efficacy and feelings of apprehension/fear when conducting reactive balance training.Being creative and improvising with equipment that is readily available in clinics enables reactive balance training, without the need for high-tech equipment.Clinicians should consider using standardized tools with reactive balance control components, such as the Balance Evaluation Systems Test or Performance Oriented Mobility Assessment, to assess balance control.

Publication Rate and Consistency of Registered Trials of Motor-Based Stroke Rehabilitation.

OBJECTIVE: To determine the publication rate of motor-rehabilitation trials poststroke and the consistency between registry records and their corresponding main publications in trial design, primary objectives and outcomes, eligibility criteria, and sample size. METHODS: We searched 18 clinical trial registries to identify randomized controlled trials of motor-based stroke rehabilitation registered after July 2005 and completed before April 2017. Eligible trials included adults with stroke, with at least one outcome measure related to motor function. Information in the registry records was compared with that of their main publications, if any. RESULTS: Three hundred twenty-three trials met our eligibility criteria; we were unable to find a peer-reviewed publication reporting the main findings for 46% (150/323) of these. Of the 169 trials with peer-reviewed articles published in English, 141 (83%) were consistent with the registry record in trial design, 100 (59%) were consistent in primary objectives, 71 (42%) were consistent in primary outcomes, 28 (17%) were consistent in eligibility criteria, and 74 (44%) were consistent in sample size. CONCLUSIONS: Approximately half of motor-based stroke rehabilitation trials were not published, even more than 3 years after the end of the trial. When main publications were found, they substantially deviated from information in the registry record. These findings highlight the importance of trial registries for identifying unpublished stroke rehabilitation trials and of searching trial registries when conducting systematic reviews and meta-analysis to help ensure that reviews are unbiased.

A survey of Canadian healthcare professionals' practices regarding reactive balance training.

Background: Perturbation-based balance training (PBT) is a relatively new type of balance training that aims to improve control of reactions to a loss of balance. This study aimed to determine the prevalence of use of PBT in clinical practice, and the most significant barriers and facilitators to implementing PBT in practice.Methods: Health-care professionals across Canada (primarily physiotherapists and kinesiologists) who provide balance training to individuals with balance impairments and/or increased fall risk completed a questionnaire that asked about knowledge and use of PBT in practice.Results: Overall, 76.3% of participants (299/392) reported that they had used PBT in their practices, with 22.4% (88/392) reporting regular PBT use. Lack of knowledge of PBT appeared to be the most significant barrier for those not currently using PBT in their practices, whereas individuals who were familiar with PBT and open to using it in practice experienced barriers related to training, knowledge, human resources, client characteristics, and the practice setting. More than 90% of respondents were interested in learning more about almost all aspects of PBT.Conclusions: These findings could be used to inform development of future educational strategies to increase uptake of PBT in rehabilitation practice.

Determining the optimal dose of reactive balance training after stroke: study protocol for a pilot randomised controlled trial.

INTRODUCTION: Falls risk poststroke is highest soon after discharge from rehabilitation. Reactive balance training (RBT) aims to improve control of reactions to prevent falling after a loss of balance. In healthy older adults, a single RBT session can lead to lasting improvements in reactive balance control and prevent falls in daily life. While increasing the dose of RBT does not appear to lead to additional benefit for healthy older adults, stroke survivors, who have more severely impaired balance control, may benefit from a higher RBT dose. Our long-term goal is to determine the optimal dose of RBT in people with subacute stroke. This assessor-blinded pilot randomised controlled trial aims to inform the design of a larger trial to address this long-term goal. METHODS AND ANALYSIS: Participants (n=36) will be attending out-patient stroke rehabilitation, and will be randomly allocated to one of three groups: one, three or six RBT sessions. RBT will replace a portion of participants' regular physiotherapy so that the total physical rehabilitation time will be the same for the three groups. Balance and balance confidence will be assessed at: (1) study enrolment; (2) out-patient rehabilitation discharge; and (3) 6 months postdischarge. Participants will report falls and physical activity for 6 months postdischarge. Pilot data will be used to plan the larger trial (ie, sample size estimate using fall rates, and which groups should be included based on between-group trends in pre-to-post training effect sizes for reactive balance control measures). Pilot data will also be used to assess the feasibility of the larger trial (ie, based on the accrual rate, outcome completion rate and feasibility of prescribing specific training doses). ETHICS AND DISSEMINATION: Institutional research ethics approval has been received. Study participants will receive a lay summary of results. We will also publish our findings in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT04219696; Pre results.

Determining Safe Participation in Aerobic Exercise Early After Stroke Through a Graded Submaximal Exercise Test.

OBJECTIVE: The benefits of aerobic exercise early after stroke are well known, but concerns about cardiovascular risk are a barrier to clinical implementation. Symptom-limited exercise testing with electrocardiography (ECG) is recommended but not always feasible. The purpose of this study was to determine the frequency of and corresponding exercise intensities at which ECG abnormalities occurred during submaximal exercise testing that would limit safe exercise prescription beyond those intensities. METHODS: This study was a retrospective analysis of ECGs from 195 patients who completed submaximal exercise testing during stroke rehabilitation. A graded submaximal exercise test was conducted with a 5- or 12-lead ECG and was terminated on the basis of predetermined endpoint criteria (heart rate, perceived exertion, signs, or symptoms). ECGs were retrospectively reviewed for exercise-induced abnormalities and their associated heart rates. RESULTS: The peak heart rate achieved was 65.4% (SD = 10.5%) of the predicted maximum heart rate or 29.1% (SD = 15.5%) of the heart rate reserve (adjusted for beta-blocker medications). The test was terminated more often because of perceived exertion (93/195) than because of heart rate limits (60/195). Four patients (2.1%) exhibited exercise-induced horizontal or downsloping ST segment depression of ≥1 mm. Except for 1 patient, the heart rate at test termination was comparable with the heart rate associated with the onset of the ECG abnormality. CONCLUSION: A graded submaximal exercise test without ECG but with symptom monitoring and conservative heart rate and perceived exertion endpoints may facilitate safe exercise intensities early after stroke. Symptom-limited exercise testing with ECG is still recommended when progressing to higher intensity exercise. IMPACT: Concerns about cardiovascular risk are a barrier to physical therapists implementing aerobic exercise in stroke rehabilitation. This study showed that, in the absence of access to exercise testing with ECG, submaximal testing with conservative heart rate and perceived exertion endpoints and symptom monitoring can support physical therapists in the safe prescription of aerobic exercise early after stroke. LAY SUMMARY: It is recommended that people with stroke participate in aerobic exercise as early as possible during their rehabilitation. A submaximal exercise test with monitoring of heart rate, perceived exertion, blood pressure, and symptoms can support physical therapists in safely prescribing that exercise.

Improvements in balance reaction impairments following reactive balance training in individuals with sub-acute stroke: A prospective cohort study with historical control.

Background: Reactive balance training (RBT) has been previously found to reduce fall risk in individuals with sub-acute stroke; however, our understanding of the effects of RBT on specific balance impairments is lacking.Objective: To quantify changes in common balance reaction impairments in individuals with sub-acute stroke resulting from RBT, relative to traditional balance training, using a prospective cohort study design with a historical control group.Methods: Individuals with sub-acute stroke completed either RBT or traditional balance training as part of their routine care during physiotherapy in inpatient rehabilitation. Reactive balance control was assessed using lean-and-release perturbations pre-intervention, post-intervention, and 6-months post-intervention (follow-up). Individuals with impaired balance reactions (delayed foot-off times, slide steps, and/or a preference for stepping with the preferred limb) at the pre-intervention assessment were identified using video and force plate data. Outcome measures (foot-off times, frequency of trials with slide steps, and stepping with the preferred limb) from the RBT participants with impaired reactions were compared for each of the three assessments to the mean values for the participants with impaired reactions in the historical control group.Results: Improvements were observed in all outcome measures for the RBT participants between pre-intervention and post-intervention, and/or between post-intervention and follow-up. These improvements were generally equivalent to, if not better than, the improvements demonstrated by the historical control group.Conclusions: Findings further support the use of RBT for post-stroke inpatient rehabilitation, and provide insight into specific balance reaction impairments that are improved by RBT.

Does perturbation-based balance training prevent falls among individuals with chronic stroke? A randomised controlled trial.

OBJECTIVES: No intervention has been shown to prevent falls poststroke. We aimed to determine if perturbation-based balance training (PBT) can reduce falls in daily life among individuals with chronic stroke. DESIGN: Assessor-blinded randomised controlled trial. SETTING: Two academic hospitals in an urban area. INTERVENTIONS: Participants were allocated using stratified blocked randomisation to either 'traditional' balance training (control) or PBT. PBT focused on improving responses to instability, whereas traditional balance training focused on maintaining stability during functional tasks. Training sessions were 1 hour twice/week for 6 weeks. Participants were also invited to complete 2 'booster' training sessions during the follow-up. PARTICIPANTS: Eighty-eight participants with chronic stroke (>6 months poststroke) were recruited and randomly allocated one of the two interventions. Five participants withdrew; 42 (control) and 41 (PBT group) were included in the analysis. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was rate of falls in the 12 months post-training. Negative binomial regression was used to compare fall rates between groups. Secondary outcomes were measures of balance, mobility, balance confidence, physical activity and social integration. RESULTS: PBT participants reported 53 falls (1.45 falls/person-year) and control participants reported 64 falls (1.72 falls/person-year; rate ratio: 0.85(0.42 to 1.69); p=0.63). Per-protocol analysis included 32 PBT and 34 control participants who completed at least 10/12 initial training sessions and 1 booster session. Within this subset, PBT participants reported 32 falls (1.07 falls/person-year) and control participants reported 57 falls (1.75 falls/person-year; rate ratio: 0.62(0.29 to 1.30); p=0.20). PBT participants had greater improvement in reactive balance control than the control group, and these improvements were sustained 12 months post-training. There were no intervention-related serious adverse effects. CONCLUSIONS: The results are inconclusive. PBT may help to prevent falls in daily life poststroke, but ongoing training may be required to maintain the benefits. TRIAL REGISTRATION NUMBER: ISRCTN05434601; Results.

Characterization of Reactions to Laterally Directed Perturbations in People With Chronic Stroke.

Background: Reactive balance control is often impaired poststroke. Studies addressing responses to laterally directed perturbations in this population are currently lacking. Given that stroke-related motor impairments are unilateral, a better understanding of reactive balance responses to these types of perturbations is critical. Objective: This study aimed to quantify differences in reactive balance control in response to laterally directed perturbations in people with chronic stroke, based on perturbation direction and ability to step with either limb. Design: This study used a cross-sectional design. Methods: Participants with chronic stroke (N = 19) were divided into groups representing their ability to step with either limb, based on performance on a reactive balance task in a baseline assessment. The preferred stepping limb was also identified during this assessment. Each participant then underwent a series of laterally directed perturbations on a motion platform. Behavioral measures were compared between platform direction and group. Results: Trials with extra steps, step initiation with the preferred limb, and crossover steps were more common with platform motion toward the preferred limb compared to the nonpreferred limb; the latter effect was only observed for participants with an impaired ability to step with either limb. Side-step sequences were more common in those able to step with either limb when the platform moved toward the preferred limb. Limitations: The participant sample was likely higher functioning than the general population of stroke survivors due to equipment constraints. Additionally, participants may have developed strategies to use the platform's motion characteristics to aid with balance recovery. Conclusions: These findings provide an indication of responses to laterally directed perturbations in people with chronic stroke and may help inform strategies for improving reactive balance control during stroke rehabilitation.

Does Perturbation Training Prevent Falls after Discharge from Stroke Rehabilitation? A Prospective Cohort Study with Historical Control.

BACKGROUND: Individuals with stroke fall frequently, and no exercise intervention has been shown to prevent falls post stroke. Perturbation-based balance training (PBT), which involves practicing reactions to instability, shows promise for preventing falls in older adults and individuals with Parkinson's disease. This study aimed to determine if PBT during inpatient stroke rehabilitation can prevent falls after discharge into the community. METHODS: Individuals with subacute stroke completed PBT as part of routine inpatient rehabilitation (n = 31). Participants reported falls experienced in daily life for up to 6 months post discharge. Fall rates were compared to a matched historical control group (HIS) who did not complete PBT during inpatient rehabilitation. RESULTS: Five of 31 PBT participants, compared to 15 of 31 HIS participants, reported at least 1 fall. PBT participants reported 10 falls (.84 falls per person per year) whereas HIS participants reported 31 falls (2.0 falls per person per year). When controlled for follow-up duration and motor impairment, fall rates were lower in the PBT group than the HIS group (rate ratio: .36 [.15, .79]; P = .016). CONCLUSIONS: These findings suggest that PBT is promising for reducing falls post stroke. While this was not a randomized controlled trial, this study may provide sufficient evidence for implementing PBT in stroke rehabilitation practice.

Perturbation training to promote safe independent mobility post-stroke: study protocol for a randomized controlled trial.

BACKGROUND: Falls are one of the most common medical complications post-stroke. Physical exercise, particularly exercise that challenges balance, reduces the risk of falls among healthy and frail older adults. However, exercise has not proven effective for preventing falls post-stroke. Falls ultimately occur when an individual fails to recover from a loss of balance. Thus, training to specifically improve reactive balance control could prevent falls. Perturbation training aims to improve reactive balance control by repeatedly exposing participants to postural perturbations. There is emerging evidence that perturbation training reduces fall rates among individuals with neurological conditions, such as Parkinson disease. The primary aim of this work is to determine if perturbation-based balance training can reduce occurrence of falls in daily life among individuals with chronic stroke. Secondary objectives are to determine the effect of perturbation training on balance confidence and activity restriction, and functional balance and mobility. METHODS/DESIGN: Individuals with chronic stroke will be recruited. Participants will be randomly assigned to one of two groups: 1) perturbation training, or 2) 'traditional' balance training. Perturbation training will involve both manual perturbations (e.g., a push or pull from a physiotherapist), and rapid voluntary movements to cause a loss of balance. Training will occur twice per week for 6 weeks. Participants will record falls and activity for 12 months following completion of the training program. Standardized clinical tools will be used to assess functional balance and mobility, and balance confidence before and after training. DISCUSSION: Falls are a significant problem for those with stroke. Despite the large body of work demonstrating effective interventions, such as exercise, for preventing falls in other populations, there is little evidence for interventions that prevent falls post-stroke. The proposed study will investigate a novel and promising intervention: perturbation training. If effective, this training has the potential to not only prevent falls, but to also improve safe independent mobility and engagement in daily activities for those with stroke. TRIAL REGISTRATION: Current Controlled Trials: ISRCTN05434601 .

Is perception of vertical impaired in individuals with chronic stroke with a history of 'pushing'?

Post-stroke 'pushing' behaviour appears to be caused by impaired perception of vertical in the roll plane. While pushing behaviour typically resolves with stroke recovery, it is not known if misperception of vertical persists. The purpose of this study was to determine if perception of vertical is impaired amongst stroke survivors with a history of pushing behaviour. Fourteen individuals with chronic stroke (7 with history of pushing) and 10 age-matched healthy controls participated. Participants sat upright on a chair surrounded by a curved projection screen in a laboratory mounted on a motion base. Subjective visual vertical (SVV) was assessed using a 30 trial, forced-choice protocol. For each trial participants viewed a line projected on the screen and indicated if the line was tilted to the right or the left. For the subjective postural vertical (SPV), participants wore a blindfold and the motion base was tilted to the left or right by 10-20°. Participants were asked to adjust the angular movements of the motion base until they felt upright. SPV was not different between groups. SVV was significantly more biased towards the contralesional side for participants with history of pushing (-3.6 ± 4.1°) than those without (-0.1 ± 1.4°). Two individuals with history of pushing had SVV or SPV outside the maximum for healthy controls. Impaired vertical perception may persist in some individuals with prior post-stroke pushing, despite resolution of pushing behaviours, which could have consequences for functional mobility and falls.

The effect of post-stroke lower-limb spasticity on the control of standing balance: Inter-limb spatial and temporal synchronisation of centres of pressure.

BACKGROUND: Challenges in stability control are common post-stroke. Although lower-limb spasticity is a common sensorimotor consequence post-stroke, its potential to further complicate stability control among stroke-survivors remains largely unknown. Advancing such understanding can help inform strategies to reduce fall risk and increase independence among these individuals. The purpose of this study was to characterise the extent of limb-specific dyscontrol among individuals with spasticity. METHODS: A retrospective analysis of 131 patients assessed for spasticity was performed. Patients selected for inclusion were categorised into two groups, with (n=19) or without (n=63) unilateral lower-limb spasticity. Two force platforms were used to determine the individual-limb and net centres of pressure in both anteroposterior and mediolateral directions during 30s of quiet standing. Limb-specific dyscontrol was assessed by calculating weight-bearing symmetry ratios, cross-correlation coefficients at zero phase-shift (temporal synchrony) and ratios of individual-limb root-mean-square displacements (spatial symmetry). Total body postural control was assessed by examining the root-mean-square of the net centre of pressure displacement. FINDINGS: The group with spasticity bore less weight on the affected limb and exhibited reduced temporal synchrony of centre of pressure displacements. There were no differences in inter-limb root-mean-square centre of pressure ratios or in the root-mean-square of the net centre of pressure displacement. INTERPRETATION: Individuals with lower-limb spasticity may have additional challenges with stability control, specifically linked to the ability to modify the location of the centre of pressure beneath the affected limb, in a time-sensitive manner so as to contribute beneficially to the control of whole body stability.

Determinants and consequences for standing balance of spontaneous weight-bearing on the paretic side among individuals with chronic stroke.

Hemiparetic stroke patients commonly bear more weight on the non-paretic side which seems intuitively linked to unilateral control deficits. However, there is evidence that some post-stroke favour weighting the paretic side, which may be problematic given altered capacity of the paretic limb to contribute to the control of upright posture. This study explores the prevalence and clinical determinants of stance asymmetry, and the relationship between stance asymmetry and postural control among chronic stroke patients. Subjects (n=147; >6 months post-stroke) stood on two force plates in eyes-open and eyes-closed conditions; 59 were symmetric, 18 had paretic asymmetry (PA), and 70 had non-paretic asymmetry (NPA). Root mean square (RMS) of antero-posterior and medio-lateral centre-of-pressure under each limb and both limbs combined were compared. RMS of total medio-lateral centre-of-pressure was greater for both asymmetric groups compared with the symmetric group. PA subjects relied less on the loaded limb for control than NPA subjects and relied more on visual information for postural control than those who were symmetric. There were no differences in the characteristics of individuals between the PA and NPA groups. The loading of the paretic limb was not related to impaired postural control during stationary standing which was attributable, in part, to individuals relying on control from the non-paretic limb, in spite of lower vertical load, and a greater dependence on visual contributions. There was no evidence that greater loading on the paretic limb was related to persisting dyscontrol but may rather reflect a learned strategy.

Between-limb synchronization for control of standing balance in individuals with stroke.

BACKGROUND: During standing, forces and moments exerted at the feet serve to maintain stability in the face of constant centre-of-mass movement. These actions are temporally synchronized in healthy individuals. Stroke is typically a unilateral injury resulting in increased sensori-motor impairment in the contra-lesional compared with the ipsi-lesional lower-limb, which could lead to reduced between-limb synchronization for control of standing balance. The purpose of this study is to investigate between-limb synchronization of standing balance control in individuals with stroke; a potentially important index of control of upright stability. METHODS: Twenty healthy controls and 33 individuals with unilateral stroke were assessed. Stability was assessed during a 30-second quiet standing trial by measuring data from two force plates (one per foot). Limb-specific centre of pressure was calculated. Between-limb synchronization was defined as the coefficient of the correlation between the left and right foot for both the antero-posterior and medio-lateral centre of pressure time series. Synchronization, weight-bearing symmetry, and root mean square of the total centre of pressure excursion were compared between controls and stroke participants. FINDINGS: Stroke participants swayed more, were more asymmetric, and had less between-limb synchronization than healthy controls. Among individuals with stroke, reduced between-limb synchronization was related to increased postural sway in the medio-lateral direction and increased weight-bearing asymmetry. INTERPRETATION: Individuals with stroke have reduced temporal synchronization of centre of pressure fluctuations under the feet when controlling quiet standing. The clinical significance of reduced synchronization remains to be determined, although it appears linked to increased medio-lateral sway and weight-bearing asymmetry.

Correlating lesion size and location to deficits after ischemic stroke: the influence of accounting for altered peri-necrotic tissue and incidental silent infarcts.

BACKGROUND: Investigators frequently quantify and evaluate the location and size of stroke lesions to help uncover cerebral anatomical correlates of deficits observed after first-ever stroke. However, it is common to discover silent infarcts such as lacunes in patients identified clinically as 'first-ever' stroke, and it is unclear if including these incidental findings may impact lesion-based investigations of brain-behaviour relationships. There is also debate concerning how to best define the boundaries of necrotic stroke lesions that blend in an ill-defined way into surrounding tissue, as it is unclear whether including this altered peri-necrotic tissue region may influence studies of brain-behaviour relationships. Therefore, for patients with clinically overt stroke, we examined whether including altered peri-necrotic tissue and incidental silent strokes influenced either lesion volume correlations with a measure of sensorimotor impairment or the anatomical localization of this impairment established using subtraction lesion analysis. METHODS: Chronic stroke lesions of 41 patients were manually traced from digital T1-MRI to sequentially include the: necrotic lesion core, altered peri-necrotic tissue, silent lesions in the same hemisphere as the index lesion, and silent lesions in the opposite hemisphere. Lesion volumes for each region were examined for correlation with motor impairment scores, and subtraction analysis was used to highlight anatomical lesion loci associated with this deficit. RESULTS: For subtraction lesion analysis, including peri-necrotic tissue resulted in a larger region of more frequent damage being seen in the basal ganglia. For correlational analysis, only the volume of the lesion core was significantly associated with motor impairment scores (r = -0.35, p = 0.025). In a sub-analysis of patients with small subcortical index lesions, adding silent lesions in the opposite hemisphere to the volume of the index stroke strengthened the volume-impairment association. CONCLUSIONS: Including peri-necrotic tissue strengthened lesion localization analysis, but the influence of peri-necrotic tissue and incidental lesions on lesion volume correlations with motor impairment was negligible barring a small index lesion. Overall, the potential influence of incidental lesions and peri-necrotic tissue on brain-behaviour relationships may depend on the characteristics of the index stroke and on whether one is examining the relationship between lesion volume and impairment or lesion location and impairment.

Association between gait asymmetry and brain lesion location in stroke patients.

BACKGROUND AND PURPOSE: Associations between the site of brain injury and poststroke gait impairment are poorly understood. Temporal gait asymmetry after stroke is a salient index of gait dysfunction that has important functional consequences. The current study investigated whether subtraction lesion analysis could distinguish brain regions associated with persisting temporal gait asymmetry in chronic stroke patients. METHODS: Analysis was conducted on 37 chronic ambulatory stroke patients (17 symmetrical gait, 20 asymmetrical gait). Spatiotemporal gait parameters were recorded using an instrumented walking surface. Lesions were traced from 3D T1-MRI, and region of interest images were generated. The lesion overlay of patients with symmetrical gait was subtracted from patients with asymmetrical gait to highlight voxels more frequently lesioned in asymmetrical patients and relatively spared in symmetrical patients. RESULTS: Demographic data were comparable between the 2 groups. Asymmetrical patients exhibited significantly higher National Institute of Health Stroke Scale neglect scores and more severe motor impairment. Gait asymmetry was significantly correlated to Chedoke-McMaster Stroke Scale leg (r=-0.767, P<0.001) and foot (r=-0.759, P<0.001) scores, whereas gait speed correlated less strongly. After subtraction analysis, injury to the posterolateral putamen was evident 60% to 80% more frequently in the asymmetrical group compared to the symmetrical group. CONCLUSIONS: In this sample of ambulatory chronic stroke patients, damage to the posterolateral putamen was associated with temporal gait asymmetry. Further advances in our understanding of the neural correlates of gait asymmetry may provide prognostic markers for future persistent gait dysfunction and lead to early targeted rehabilitation when key regions are damaged.

Gait asymmetry in community-ambulating stroke survivors.

OBJECTIVES: To determine the prevalence and severity of asymmetry among independently ambulating stroke survivors and to establish the association between velocity and asymmetry. DESIGN: Descriptive analysis. SETTING: Research gait laboratory in a Canadian hospital. PARTICIPANTS: Community-dwelling, independently ambulating participants (N=54) with chronic stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Overground gait velocity, symmetry ratios for temporal and spatial step parameters, and motor impairment of the foot and leg. Spatiotemporal parameters were collected with a pressure-sensitive mat. Motor impairment was measured clinically with the Chedoke-McMaster Stroke Assessment. RESULTS: Thirty (55.5%) participants showed statistically significant temporal asymmetry and 18 (33.3%) exhibited statistically significant spatial asymmetry. Preferred velocity was negatively associated with temporal asymmetry (r=-.583, df=52, P<.001) but not spatial asymmetry (r=-.146, df=52, P=.29). Temporal asymmetry was also associated with motor recovery of the leg (r=-.644, df=35, P<.001) and foot (r=-.628, df=35, P<.001). CONCLUSIONS: The results of the current study illustrate that temporal asymmetry can be found in many independently ambulating stroke patients. The work highlights the need for a standard assessment of poststroke gait symmetry in light of the complex relationship with motor impairment and velocity.

Physiotherapy coupled with dextroamphetamine for rehabilitation after hemiparetic stroke: a randomized, double-blind, placebo-controlled trial.

BACKGROUND AND PURPOSE: Hemiparesis is the commonest disabling deficit caused by stroke. In animals, dextroamphetamine (AMPH) paired with training enhances motor recovery, but its clinical efficacy is uncertain. METHODS: In a randomized, double-blind, placebo-controlled trial, 71 stroke patients were stratified by hemiparesis severity and randomly assigned to 10 sessions of physiotherapy coupled with either 10 mg AMPH or placebo. Study treatments were administered by 1 physiotherapist, beginning 5 to 10 days after stroke and continuing twice per week for 5 weeks. Outcomes were assessed by 1 physiotherapist at baseline, after each treatment session, at 6 weeks, and at 3 months. The primary outcome was motor recovery (impairment level) on the Fugl-Meyer (FM) scale. Secondary outcomes assessed mobility, ambulation, arm/hand function, and independence in activities of daily living. RESULTS: Baseline hemiparesis was severe overall (mean FM score 27.7+/-20.0). Motor scores improved during treatment in both groups (mean change, baseline to 3 months 29.5+/-16.6). Repeated-measures ANOVA revealed no significant differences in recovery between the treatment groups for the entire cohort (n=67) or for subgroups with a severe hemiparesis (n=43), moderate hemiparesis (n=24), or cortically based stroke (n=26). In the moderate subgroup, there was a significant drug x time interaction for upper extremity motor recovery (F=5.14; P<0.001), although there was a significant baseline imbalance in motor scores in this subgroup. CONCLUSIONS: In stroke patients with a severe motor deficit, 10 mg AMPH coupled with physiotherapy twice per week for 5 weeks in the early poststroke period provided no additional benefit in motor or functional recovery compared with physiotherapy alone. Patients with moderate severity hemiparesis deserve further investigation. Increased intensity and longer duration drug/therapy dosing regimens should be explored, targeting the upper and lower limbs separately.

Poststroke "pushing": natural history and relationship to motor and functional recovery.

BACKGROUND AND PURPOSE: Patients with hemiparetic stroke have impaired balance control. Some patients ("pushers") are resistant to accepting weight on and actively "push" away from the nonparetic side. This research identified pushers from stroke patients with moderate to severe hemiparesis and examined longitudinal changes in symptoms, level of impairment, and functional independence. METHODS: Prospective sample of hemiparetic stroke patients (n=65) located in Toronto, Canada. Detailed clinical assessments were performed within 10 days postonset, at 6 weeks, and at 3 months. RESULTS: At 1 week after stroke, 63% of patients demonstrated features of pushing. In 62% of pushers, symptoms resolved by 6 weeks, whereas in 21%, pushing symptoms persisted at 3 months. Motor recovery and functional abilities at 3 months were significantly lower among the pushers compared with the nonpushers. Pushers also had a significantly longer hospital length of stay (89 days versus 57 days). It is noteworthy that motor and functional recovery improved significantly over the 3-month study period for both pushers and nonpushers. CONCLUSIONS: Identification of stroke patients with pushing symptoms has prognostic implications for recovery. In light of this potential recovery, rehabilitation specialists need to refine treatment approaches for the pushers to further improve functional outcome.