PurposeIndividuals with stroke have difficulty rotating their trunk and adjusting their supporting foot when negotiating spatial constraints. This study aimed to classify movement patterns used when passing through narrow openings and to identify factors associated with stroke-specific patterns.MethodsTwenty-three individuals with stroke (age: 60.7 ± 10.1 years, time after stroke: 15.2 ± 21.1 months, subacute and chronic, independently ambulatory), 23 age-matched community-dwelling adults (61.0 ± 9.7 years), and 12 young adults (25.4 ± 2.5 years) were recruited. Participants walked through openings of various widths. Movement patterns were independently classified by three trained physical therapists, and inter-rater agreement was assessed. Generalized linear mixed models with participants as a random effect were used to examine associations between pattern selection and clinical/environmental factors.ResultsFive passing patterns were identified: (A) pivot, (B-1) early pivot, (B-2) early pivot with reverse trunk rotation, (C) multiple steps, and (D) no-rotation. Inter-rater agreement was substantial (Cohen's κ = .76). Stroke-specific patterns were patterns B-2 and C. The mixed-model analysis showed that B-2 and C were more likely with narrower openings (odds ratio [OR]: .52, 95% confidence interval [CI]: .39-.70; and OR: .18, 95% CI: .11-.32, respectively; both p < .001). TUG performance was not significantly associated with pattern C (OR: 1.22, 95% CI: .99-1.49, p = .056).ConclusionOpening width was associated with stroke-specific pattern selection. Multi-step strategies may reflect increased stability demands, whereas pivot-like strategies may be associated with better mobility. These findings may help clinicians assess movement behaviors in constrained environments.

BackgroundOlder adults frequently rely on spin turns while walking, a turning strategy that is biomechanically less stable than step turns and has been associated with an increased risk of falls. Previous studies have suggested that increased gaze fixation toward the area near the feet may be related to this tendency; however, the determinants of increased spin-turn use, particularly the causal role of gaze fixation, remain unclear. The present study aimed to examine whether constraining gaze fixation to the near walking location increases the use of spin turns during walking in older adults.MethodsFifteen older adults (73.5 ± 6.3 years) and 12 younger adults (24.8 ± 3.7 years) performed a double-target stepping walking task in which the turning strategy (step turn or spin turn) was determined by foot placement relative to a second target. Gaze fixation was experimentally constrained to either a near or a far-gaze condition before stepping onto the first target. Eye movements were recorded using a mobile eye-tracking system, and whole-body kinematics were collected using a three-dimensional motion analysis system. The proportion of spin turns, frequency of pivot switching, gaze behavior, and spatiotemporal gait parameters were analyzed using generalized linear mixed models.ResultsThe proportion of spin turns was significantly higher under the near-gaze condition than under the far-gaze condition across both age groups, with no statistically significant difference in the magnitude of this effect between older and younger adults. Increased use of spin turns was accompanied by reduced gaze fixation on the far area during the reaching phase, shorter step length, and increased step count. Notably, older adults exhibited unnecessary pivot switching even in conditions in which a strategy change was not required. In contrast, younger adults primarily adjusted their gait patterns according to pivot-switch demands and showed less pronounced effects of gaze condition during turning strategy selection.ConclusionThese findings identify gaze fixation as a key determinant of increased spin-turn use during turning in older adults, whereby constraining gaze to the near walking surface alters visual information available for step planning and promotes maladaptive turning strategy selection.

Safety management of the paretic side is critical for stroke individuals. We previously demonstrated that stroke individuals who walk through an opening while entering from the paretic side have a reduced incidence of collisions with the opening frame. We investigated whether lower visual field restriction and cognitive load affect collision avoidance performance when individuals with stroke enter narrow openings from the paretic side. Seventeen stroke participants repeatedly walked through the opening under three task conditions: one control and two constraints (downward visual field restriction and calculation). Each participant performed the task by entering an opening with a width equal to their shoulder width, from either the paretic or non-paretic side. Collision events were analyzed using logistic regression models, including Generalized Linear Mixed Models (GLMMs) to account for repeated measures within participants. For task performance time, both ordinary least squares regression and linear mixed-effects models were employed to examine the effects of condition and entry direction, while controlling for individual variability. No differences were observed in the collision rate or task performance time across conditions regardless of the direction of entry into the opening. The GLMM analysis did not reveal any significant predictors of collisions, although a trend toward an association with the relative perceptual boundary was observed. In contrast, performance time was prolonged by visual restriction, calculation task, paretic side entry, and reduced balance. The present study suggests that overestimation of one’s own ability to walk through narrow openings may be related to decreased safety, whereas visual restriction, cognitive load, use of the paretic side, and reduced balance ability are associated with decreased efficiency.

Reports on the relationship between freezing of gait (FoG) and visual search behavior in Parkinsonian syndrome remain limited. This study aimed to examine gaze behavior in three patients with progressive supranuclear palsy during doorway walking trials. Contrary to previous case reports, substantial individual variability was observed in gaze fixation patterns and blink rates during the FoG episodes. In conclusion, the relationship between visual search behavior and freezing is more complex than previously understood.

BACKGROUND:Individuals with stroke have difficulty adapting their walking to their environment; the upper extremity on the paretic side is particularly prone to colliding with surfaces when walking through openings. OBJECTIVES:We aim to investigate how individuals with stroke with different levels of upper extremity motor paralysis rotate each part of their upper body for safe obstacle avoidance. METHODS:Participants included eight, 17, and 19 individuals in the moderate (MDR), mild (MLD), and control groups, respectively. Participants were asked to walk through door-like openings of four different widths without colliding with them. Each participant performed the task by entering either from the paretic side or the nonparetic side. To examine the effects of the group, entering direction, and opening width on rotation angles we conducted a statistical analysis using a Generalized Linear Mixed Model. RESULTS:For the head angle, the main effect of group was significant (p = .011). Post hoc multiple comparisons showed that the angle was significantly larger in the MDR than that in the MLD and control groups (both p < .001). Shoulder and hip rotation angles did not differ significantly between groups. Although some interaction effects between the group and opening width were observed, no consistent interaction patterns were found across body segments. CONCLUSIONS:The results were interpreted in terms of motor difficulty and visual attention. Therefore, individuals with stroke who had moderate upper extremity paralysis may have rotated their heads at higher angles due to difficulty with movement adjustments and increased visual attention demands.

BACKGROUND:High collision rates and frequency of entering the opening from non-paretic sides are associated with collision in individuals with stroke. OBJECTIVE:To identify factors associated with collision avoidance behavior when individuals with stroke walked through narrow openings. METHODS:Participants with subacute or chronic stroke walked through a narrow opening and had to avoid colliding with obstacles. Multiple regression analyses were conducted with pathophysiology, motor function, and judgment ability as predictor variables; collision rate and frequency of entering the opening from non-paretic sides were outcome variables. RESULTS:Sixty-one eligible individuals with stroke aged 63±12 years were enrolled. Thirty participants collided twice or more and 37 entered the opening from the non-paretic side. Higher collision occurrence was associated with slower Timed Up and Go tests and left-right sway (odds ratios, 1.2 and 5.6; 95% confidence intervals, 1.1-1.3 and 1.3-28.2; p = .008 and.025, respectively). Entering from non-paretic sides was associated with lesions in the thalamus, left-sided hemiplegia, and Brunnstrom stage 3 or lower (odds ratios, 6.6, 8.7, and 6.7; 95% confidence intervals, 1.3-52.5, 2.5-36.5, and 1.2-57.5; and p = .038,.001, and.048, respectively). CONCLUSION:Walking ability is associated with avoiding obstacle collision, while pathophysiological characteristics and degree of paralysis are associated with a preference for which side of the body enters an opening first. Interventions to improve walking ability may improve collision avoidance. Avoidance behavior during intervention varies depending on the lesion position.

PURPOSE:Paretic side collisions frequently occur in stroke patients, especially while walking through narrow spaces. We determined whether training for walking through an opening (T-WTO) while entering from the paretic side would improve collision avoidance behavior and prevent falls after 6 months.MATERIALS AND METHODS:Thirty-eight adults with moderate-to-mild hemiparetic gait after stroke who were hospitalized in a rehabilitation setting were randomly allocated to the T-WTO (n = 20) or regular rehabilitation (R-Control; n = 18) program. Both groups received five sessions of 40 min per week, for three weeks total. T-WTO included walking through openings of various widths while rotating with the paretic side in front, and R-Control involved normal walking without body rotation. Obstacle avoidance ability, 10-m walking test, timed Up and Go test, Berg Balance Scale, Activities-specific Balance Confidence, the perceptual judgment of passability, and fall incidence were assessed.RESULTS:Collision rate and time to passage of the opening in obstacle avoidance task significantly improved in the T-WTO group compared with those in the R-Control group. Contrast, T-WTO did not lead to significant improvements in other outcomes.CONCLUSIONS:T-WTO improved efficiency and safety in managing subacute stroke patients. Such training could improve patient outcomes/safety because of the paretic body side during walking.CLINICAL TRIAL REGISTRATION NO.:R000038375 UMIN000033926.

Muroi et al. show that individuals with stroke have improved collision avoidance behavior when passing through an aperture while entering from the paretic-side of the body. However, the underlying mechanism remains unknown. We reanalyzed Muroi et al.'s data to reveal how individuals with stroke walk through an aperture by examining changes in walking velocity and behavioral complexity (i.e., sample entropy, an index of (ir)regularity of time series, regarded lower entropy as more regular and less complex) by focusing on the approaching process. The results showed that individuals with stroke reduced their walking velocity and behavioral complexity before passing through the narrow aperture when approaching from the paretic side. We interpreted that the improved obstacle avoidance when penetrating from the paretic side may be due to careful body rotation and adjusting the walking velocity in advance.

Unilateral spatial neglect (USN) is defined as the inability to attend and see on one side, which seriously interferes with daily life. Clinically, patients with left USN commonly demonstrate a striking immediate capture of attention from ipsilesional, right-sided items as soon as a visual scene unfolds (i.e., magnetic attraction [MA]). Therefore, this preliminary study utilized a three-dimensional (3D) virtual environment to evaluate the effects of eliminating stimuli in the rightward space and directing attention to the left on neglect symptoms. Methods: Seven patients with USN participated in this study, and two types of visual stimuli were created: the numbers and objects in the 3D virtual environment. To eliminate the visual stimuli on the right side, a moving slit was introduced in the virtual environment. During the experiment, patients were required to orally identify each object and number both in moving and nonmoving slit conditions. Results: A statistical comparison of scores with and without the moving slit in the 3D virtual space indicated significant changes in the object stimuli condition; however, no statistically significant difference was observed in the number stimuli condition. Conclusions: Masking the right side within the 3D virtual space increased the number of objects that can be recognized on the left side by patients with USN. The results may allow interventions in a virtual reality environment that closely resembles the patient’s real-life space.Clinical Relevance—Magnetic attraction is a symptom seen in patients in clinical practice, but there is no method of rehabilitation. The proposed moving slit method is expected to be effective because it enables attention guidance in a three-dimensional space.

We investigated the effect of a 3-week intervention-wherein a patient with unilateral spatial neglect walks through a narrow opening while entering from the contralesional side-to improve walking ability or ADL. A 66-year-old man was diagnosed with right parietal subcortical hemorrhage. We used an ABA single-case design; period B was set as the intervention. The intervention improved the continuous walking distance and balance ability and decreased the number of collisions when walking through the narrow opening; however, it exerted minimal effect on ADL. Thus, the intervention may effectively improve continuous physical or spatial attention behavior, regardless of ADL improvement.

In stroke patients, sensory loss often reduces the sensation of ground contact, which impairs motor learning during rehabilitation. In our previous study, we proposed a vibro-tactile biofeedback system (which we called the perception–empathy biofeedback system) for gait rehabilitation. The results of our 9-week pilot clinical test suggested that patients who had reached the autonomous phase in gait learning had difficulty noticing the external vibratory feedback provided by the biofeedback system, leading to ineffective intervention. We considered the possibility that slower walking speed might return the patient to the association phase and allow patients to improve their gait according to the sensory feedback provided. Thus, in this research, a method based on reducing walking speed to guide patients' attention was derived. A pilot clinical trial shows that there is a statistically significant increase of ankle dorsiflexion in the initial contact phase and increase of ankle plantarflexion in the push-off phase after vibro-tactile biofeedback system intervention with speed reduction, compared to intervention without speed reduction. The results suggest that, by reducing their walking speed during intervention, patients return to the association phase and recognize external vibratory feedback, which may result in better intervention effects.Clinical Relevance—This study provides knowledge about the optimal walking speed when using vibro-tactile biofeedback for motor learning in stroke patients.

BACKGROUND:Safety management of the paretic side of the body is critical for individuals with stroke. We previously reported that individuals with stroke who walk through an aperture while penetrating from the paretic side had fewer collisions with the frame of an aperture than did those penetrating from the non-paretic side. We observed spontaneous behavior of collision avoidance in our previous study; this study thus used penetration from the paretic and non-paretic sides as independent variables to confirm the usefulness of penetrating from the paretic side.OBJECTIVE:This study aimed to (1) reconfirm whether walking through a narrow space while penetrating from the paretic side leads to reduced frequency of collision only for individuals with stroke with previous falls by manipulating the direction of penetration as independent variables and to (2) determine whether the behavioral or cognitive characteristics of passing through the aperture are observed in individuals with stroke who had previous falls.METHODS:Individuals with stroke (12 with previous falls, 13 without) were required to walk through a narrow space while penetrating from the paretic and non-paretic sides. The collision rate and kinematic characteristics at the moment of crossing the aperture (body rotation angle, deviation of body's midpoint, and movement speed) were recorded as dependent variables. We also confirmed whether the participants expected collision after passing.RESULTS:Individuals with stroke with previous falls were less likely to have a collision when penetrating from the paretic side. The stroke fall group was likely to experience more collisions because of deleterious changes in body rotation angle and movement speed in narrow apertures. Moreover, individuals with stroke have many unexpected collisions, but the decline in anticipatory ability was not unique to the stroke fall group.CONCLUSIONS:Penetrating a narrow space from the paretic side improved safety management of the paretic side in patients with previous falls despite poor adjustment to narrow apertures. Penetrating a narrow space from the paretic side may make it easier to view and pay attention to the paretic side.

Objectives To accumulate evidence that obstacle avoidance training alone is effective in improving the locomotor ability of individuals with stroke. Design Systematic review and meta-analysis. Setting MEDLINE, EMBASE, CENTRAL, ICTRP and PEDro were searched for related information until December 2018. Two independent reviewers extracted data. Outcome measurement data were subjected to meta-analyses using random-effects models. Data syntheses were conducted using RevMan V.5.3, and the certainty of evidence was determined using the Grading of Recommendations Assessment, Development, and Evaluation approach. Participants Participants with various types and phases of stroke were included. Intervention The usual gait training including obstacle avoidance training (interventions of any type, intensity, duration and frequency). Primary and secondary outcome measures Primary outcomes were gait speed, composite gait ability and objective balance ability. Secondary outcomes were subjective balance ability, gait endurance and fall incidence. Results Two randomised controlled trials with a total of 49 participants were used as data sources for this study. The obstacle avoidance training (training) group had lower gait speed than the control group (mean difference (MD) 0.03, 95% CI −0.11 to 0.16, p=0.51). Further, the certainty of evidence was very low. The subjective balance ability (Activities-specific Balance Confidence scale) was not significantly different between the training and control groups (MD 6.65, 95% CI −7.59 to 20.89, p=0.36), and it showed very low certainty of evidence. Conclusions Obstacle avoidance training may have little or no effect on individuals with stroke. The failure to find the effectiveness of obstacle avoidance training alone is possibly attributable to the insufficient amount of training in the intervention and the lack of well-designed studies that measured relevant outcomes. PROSPERO registration number CRD42017060691.

In clinical practice, therapists often encounter cases of unilateral spatial neglect (USN) observed in far and near space. In this case report, immersive virtual reality (VR) technology was adopted as a therapy tool in a patient with stroke with severe near and far space neglect. Neuropsychological tests in near and far space as well as the Catherine Bergego Scale (CBS), as an index of neglect in daily living, were measured preintervention and postintervention. Improvement of neuropsychological tests, particularly in far space, was clearly demonstrated postintervention. However, CBS score did not change postintervention. This may be because the patient unsuccessfully translated these visual search task skills used in far space to activities of daily living. Our findings suggest the potential use of immersive VR technology in patients with USN and highlight the VR programme's limited ability to fully recover a patient's disability in natural settings.

Unilateral spatial neglect (USN) is defined as failure to report, respond, or adjust to novel or meaningful stimuli presented to the side opposite a brain lesion. This symptom deteriorates the rehabilitation efficiency and hinders activities of daily living. USN is classified into 2 sub-categories: body-centered neglect and object-centered neglect. No optimal intervention has been proposed for treating object-centered neglect. Thus, we developed a visual cueing system using immersive virtual reality to improve object-centered neglect. A feasibility study showed 2 typical measurements for object-centered neglect tended to improve the symptom, these results provide preliminary evidence for designing successful rehabilitation programs using a visual cueing system in patients with object-centered neglect.

OBJECTIVE:Walking through a narrow aperture requires unique postural configurations, i.e., body rotation in the yaw dimension. Stroke individuals may have difficulty performing the body rotations due to motor paralysis on one side of their body. The present study was therefore designed to investigate how successfully such individuals walk through apertures and how they perform body rotation behavior. METHOD:Stroke fallers (n = 10), stroke non-fallers (n = 13), and healthy controls (n = 23) participated. In the main task, participants walked for 4 m and passed through apertures of various widths (0.9-1.3 times the participant's shoulder width). Accidental contact with the frame of an aperture and kinematic characteristics at the moment of aperture crossing were measured. Participants also performed a perceptual judgment task to measure the accuracy of their perceived aperture passability. RESULTS AND DISCUSSION:Stroke fallers made frequent contacts on their paretic side; however, the contacts were not frequent when they penetrated apertures from their paretic side. Stroke fallers and non-fallers rotated their body with multiple steps, rather than a single step, to deal with their motor paralysis. Although the minimum passable width was greater for stroke fallers, the body rotation angle was comparable among groups. This suggests that frequent contact in stroke fallers was due to insufficient body rotation. The fact that there was no significant group difference in the perceived aperture passability suggested that contact occurred mainly due to locomotor factors rather than perceptual factors. Two possible explanations (availability of vision and/or attention) were provided as to why accidental contact on the paretic side did not occur frequently when stroke fallers penetrated the apertures from their paretic side.

The present study addressed whether visual information about the width of an aperture, obtained at a distance, would be sufficient to guide walking through the aperture without collision. For this purpose, we asked twelve young participants to walk while holding a 66-cm horizontal bar (bar length needs to be considered in order to perceive space necessary for crossing) and pass through an aperture without vision from 3 m in front of the aperture. Participants performed the tasks under each of four visual conditions, which differed in how vision was available: observation for 1.5 s while standing (static vision), observation during two forward steps and stopping (dynamic vision), observation during two forward steps and not stopping (dynamic vision with nonstop walking), and full vision. The results showed that, for narrow apertures (the widths were 0.8 and 1.0 times the bar length), the rate of collision without vision was about 40–50 %. This was mainly due to the maladaptive planning of body rotation. For the aperture 1.0 times the bar length, the percentage of trials with no body rotation was high, suggesting that at least some participants underestimated the space necessary for crossing. The location at which maximum body rotation occurred became farther from the obstacle, which may have been related to decreased movement speed. The availability of dynamic visual sampling during two forward steps did not contribute to improving collision avoidance. These results suggest that, while fundamental locomotor patterns are maintained even without online vision, both the underestimation of space required for crossing and the lack of fine-tuning of behavior prior to crossing increased collision rates.

Background: Unilateral spatial neglect (USN) is defined as impaired ability to attend and see on one side, and when present, it interferes seriously with daily life. These symptoms can exist for near and far spaces combined or independently, and it is important to provide effective intervention for near and far space neglect. Objective: The purpose of this pilot study was to propose an immersive virtual reality (VR) rehabilitation program using a head-mounted display that is able to train both near and far space neglect, and to validate the immediate effect of the VR program in both near and far space neglect. Methods: Ten USN patients underwent the VR program with a pre-post design and no control. In the virtual environment, we developed visual searching and reaching tasks using an immersive VR system. Behavioral inattention test (BIT) scores obtained pre- and immediate post-VR program were compared. Results: BIT scores obtained pre-and post-VR program revealed that far space neglect but not near space neglect improved promptly after the VR program. This effect for far space neglect was observed in the cancelation task, but not in the line bisection task. Conclusions: Positive effects of the immersive VR program for far space neglect are suggested by the results of the present pilot study. However, further studies with rigorous designs are needed to validate its clinical effectiveness.

We investigated whether a biofeedback system that provided supplementary vibrotactile sensory cues associated with the center of foot pressure displacement contributes to postural control in a patient with transtibial amputation. Postural stability using a force plate revealed improved stability of the bipedal posture only in the eyes-closed condition, but not in the eyes-open condition, and this effect had a brief carry-over effect. We found that this patient achieved postural control mainly using visual information, and since the vibrotactile biofeedback improved postural stability in the eyes-closed condition, there seems to exist sensory substitution for postural control. This confirms the potential of a haptic-based BF system for balance training, both in routine clinical practice and in everyday life.