Understanding gait control in post-stroke: implications for management

Towards meaningful community ambulation in individuals post stroke through use of a smart hip exoskeleton: A preliminary investigation

Stroke is the leading cause of long-term disability in the United States, leaving survivors with profound mobility challenges that impact independent community ambulation. Evidence shows assistance at the hip during walking may be beneficial for stroke survivors. In this cross-over design study, we examine the impact of a novel hip exoskeleton on both functional and patient reported outcomes measuring speed, fall risk, gait symmetry, energy expenditure and perceived walking ability during both indoors and outdoors in single and serial counting dual task paradigms. Nine ambulatory stroke survivors with hemiplegia were included. No differences were seen between the exoskeleton and baseline conditions for any outcomes. Only the patient reported outcome in which subjects were asked to rate their ability to walk outdoors approached statistical significance (p = 0.051) with greater improvement reported for the exoskeleton condition. When asked to rate several key factors about the exoskeleton, weight and assistance emerged as primary perceived negative factors of the exoskeleton underscoring the need for improvements to the technology in this area. Despite lack of differences across groups, some individuals responded positively to the exoskeleton for several functional outcomes measured, highlighting the need for additional exploration into the use of personalized hip exoskeletons for post-stroke rehabilitation.

Pathophysiological changes of muscle after ischemic stroke: a secondary consequence of stroke injury

Sufficient clinical evidence suggests that the damage caused by ischemic stroke to the body occurs not only in the acute phase but also during the recovery period, and that the latter has a greater impact on the long-term prognosis of the patient. However, current stroke studies have typically focused only on lesions in the central nervous system, ignoring secondary damage caused by this disease. Such a phenomenon arises from the slow progress of pathophysiological studies examining the central nervous system. Further, the appropriate therapeutic time window and benefits of thrombolytic therapy are still controversial, leading scholars to explore more pragmatic intervention strategies. As treatment measures targeting limb symptoms can greatly improve a patient's quality of life, they have become a critical intervention strategy. As the most vital component of the limbs, skeletal muscles have become potential points of concern. Despite this, to the best of our knowledge, there are no comprehensive reviews of pathophysiological changes and potential treatments for post-stroke skeletal muscle. The current review seeks to fill a gap in the current understanding of the pathological processes and mechanisms of muscle wasting atrophy, inflammation, neuroregeneration, mitochondrial changes, and nutritional dysregulation in stroke survivors. In addition, the challenges, as well as the optional solutions for individualized rehabilitation programs for stroke patients based on motor function are discussed.

Characteristics of limb kinematics in the gait disorders of post-stroke patients

Post-stroke gait disorders involve altered lower limb kinematics. Recently, the endpoint of the lower limb has been used as a control variable to understand gait kinematics better. In a cross-sectional study of sixty-seven post-stroke patients, the limb extension angle and effective limb length during gait were used as input variables with a mixed Gaussian model-based probabilistic clustering approach to identify five distinct clusters. Each cluster had unique characteristics related to motor paralysis, spasticity, balance ability, and gait strategy. Cluster 1 exhibited high limb extension angle and length values, indicating increased spasticity. Cluster 2 had moderate extension angles and high limb lengths, indicating increased spasticity and reduced balance ability. Cluster 3 had low limb extension angles and high limb length, indicating reduced balance ability, more severe motor paralysis, and increased spasticity. Cluster 4 demonstrated high extension angles and short limb lengths, with a gait strategy that prioritized stride length in the component of gait speed. Cluster 5 had moderate extension angles and short limb lengths, with a gait strategy that prioritized cadence in the component of gait speed. These findings provide valuable insights into post-stroke gait impairment and can guide the development of personalized and effective rehabilitation strategies.

Image Findings as Predictors of Fall Risk in Patients with Cerebrovascular Disease

This study examined computed tomography findings in patients with cerebrovascular disease and determined predictors for falls. Images of the head were divided into 13 regions, and the relationships between computed tomography findings and the presence or absence of falls were investigated. A total of 138 patients with cerebrovascular disease (66% men, aged 73.8 ± 9.6 years) were included. A comparison between the fall and non-fall groups revealed a significant difference in the total functional independence measure scores and imaging findings at admission. Logistic regression analysis showed that the thalamus (p < 0.001), periventricular lucency (p < 0.001), lateral hemisphere room enlargement (p < 0.05), and age (p < 0.05) were related to the presence or absence of falls. For the 42 patients with cerebral hemorrhage, the thalamus (p < 0.01), periventricular lucency (p < 0.05), lateral ventricle vicinity (p < 0.05), and posterior limb of the internal capsule (p < 0.05) were extracted as factors related to the presence or absence of falls. For the 96 patients with cerebral infarction, the thalamus (p < 0.001), periventricular lucency (p < 0.01), and anterior limb of the internal capsule (p < 0.05) were extracted as factors related to the presence or absence of falls. This study found a relationship between the thalamus, lateral ventricle enlargement, periventricular lucency, and falls. Fall prognosis can potentially be predicted from computed tomography findings at admission.

The effects of Robot-assisted gait training and virtual reality on balance and gait in stroke survivors: A randomized controlled trial

BACKGROUND

Stroke survivors often experience balance and gait problems, which can affect their quality of life and independence in daily living activities. Robot-assisted gait training, such as Lokomat with virtual reality, has been found to be effective in improving gait and balance. However, the specific effects of each virtual reality application on balance and spatiotemporal parameters of gait are not yet established. This study aims to investigate the effects of different virtual reality applications on these parameters.

RESEARCH QUESTION

What are the specific effects of each Lokomat augmented performance feedback application on balance and spatiotemporal parameters of gait in stroke survivors?

METHODS

The study is a randomized controlled trial conducted with four groups: Control Group, Endurance Group, Attention and Motivation Group, and Activity Timing Group. All participants received six weeks of physiotherapy, and Lokomat groups had additional robot-assisted gait training with Lokomat for three days a week. The Endurance group used Lokomat with Faster, Attention and Motivation Group with Gabarello and Smile, and Activity Timing Group with Curve Pursuit, Treasures, and High Flyer applications. Various tests were used to assess walking and balance in the study (gait analysis, 6-minute walk test, 10-meter walk test, Berg Balance Scale, postural stability, and limits of stability).

RESULTS AND SIGNIFICANCE

The study involved 56 male stroke survivors (mean age: 60.02 ± 6.83 years, post-stroke time: 238.88 ± 40.88 days). All groups improved walking speed and distance significantly, but Endurance was better (p < 0.001). Balance improved significantly in all groups, but Attention and Motivation was superior in Berg Balance Scale, postural stability, and limits of stability (p < 0.001). The selection of virtual reality applications during robot-assisted gait training according to rehabilitation goals is important for successful rehabilitation, as these applications may have varying effects on balance and walking.

Validation and reproducibility of the Glittre activities of the daily living test for evaluation of functional capacity after a stroke

METHODS

Thirty patients with hemiparesis stemming from a stroke and 20 healthy peers were evaluated. Reproducibility was determined using the intraclass correlation coefficient (ICC), standard measurement error (SME), minimum detectable change (MDC), and Bland-Altman analysis. For construct validity, the Glittre ADL test was correlated with the Six-Minute Walk Test (6MWT), Timed Up and Go Test (TUG), and Functional Independence Measure (FIM), and analyzed based on convergent validity and the comparison of known groups (stroke survivors and healthy peers).

RESULTS

Intra- and inter-observer reliability were excellent (ICC_3,1 = 0.98; 0.96, respectively). Intra-observer SME ranged from 0.27 to 0.31 minutes and inter-observer SME was 0.45 minutes. Intra-observer MDC ranged from 1.44 to 1.54 minutes and inter-observer MDC was 1.86 minutes. Strong statistically significant correlations were found between time on the Glittre ADL test and time on the 6MWT (rh = -0.91; p < .001) and TUG test (rh = 0.82; p < .001), whereas a moderate correlation was found with the FIM (rh = -0.47; p < .008).

CONCLUSIONS

The Glittre ADL test is valid for assessing functional capacity in stroke patients. It demonstrated good convergent and construct validity and excellent intra- and inter-observer reproducibility.

Bilateral ankle deformities affects gait kinematics in chronic stroke patients

Objectives

Stroke patients suffer from ankle joint deformities due to spastic ankle muscles. This study evaluated the viability of using 3D scanned surface images of the feet of stroke victims to visually assess the deformities of a hemiparetic foot and investigated the influences of deformed ankle joints on gait kinematics.

Methods

A total of 30 subjects with stroke-induced hemiparesis and 11 age-matched healthy controls completed the clinical assessments. We analyzed their feet's morphometric characteristics using a 3D scanner, identified convenient anthropometric measurements, and conducted gait trials on even and uneven terrains. The 3D foot morphometric characteristics were evaluated using the geometric morphometrics method (GMM).

Results

Results showed that there were significant differences in bilateral foot shapes between the chronic stroke patients and healthy controls and between the paretic and non-paretic sides in the chronic stroke patients. In stroke patients, those with the smaller medial malleoli's vertical tilt angles showed significantly different ankle ranges of motion of dorsi-/plantar flexion during gaits on uneven terrains (p = 0.009). In addition, those with the greater medial malleoli's vertical tilt angles showed significantly different ankle ranges of motion of inversion/eversion during gaits on even and uneven terrains (p < 0.05).

Conclusion

Using 3D scanning technology, bilateral morphometric changes in the feet of chronic stroke patients were shown by GMM and the simple anthropometric measurements identified its shape deformities in the feet. Their possible effects on gait kinematics while walking on uneven terrains were investigated. Current methodology can be potentially useful in applying conventional productions of clinically manufactured, patient-fitted ankle-foot-orthosis in orthotics and prosthetics, and in detecting various unidentified pathological deformities in the feet.

Effect of galvanic vestibular stimulation applied at the onset of stance on muscular activity and gait cycle duration in healthy individuals

Locomotion requires the complex involvement of the spinal and supraspinal systems. So far, the role of vestibular input in gait has been assessed mainly with respect to gait stability. The noninvasive technique of galvanic vestibular stimulation (GVS) has been reported to decrease gait variability and increase gait speed, but the extent of its effect on spatiotemporal gait parameters is not fully known. Objective: Characterize vestibular responses during gait and determine the influence of GVS on cycle duration in healthy young participants. Methods: Fifteen right-handed individuals participated in the study. Electromyography (EMG) recordings of the bilateral soleus (SOL) and tibialis anterior muscles (TA) were performed. First, to determine stimulation intensity, an accelerometer placed on the vertex recorded the amplitude of the head tilts evoked by the GVS (1-4 mA, 200 ms) to establish a motor threshold (T). Second, while participants walked on a treadmill, GVS was applied at the onset of the stance phase during the treadmill gait with an intensity of 1 and 1.5 T with the cathode behind the right (RCathode) or left ear (LCathode). EMG traces were rectified, averaged (n = 30 stimuli), and analyzed. Latency, duration, and amplitude of vestibular responses as well as the mean duration of the gait cycles were measured. Results: GVS mainly induced long-latency responses in the right SOL, right TA and left TA. Only short-latency responses were triggered in the left SOL. Responses in the right SOL, left SOL and left TA were polarity dependent, being facilitatory with RCathode and inhibitory with LCathode, whereas responses in the right TA remained facilitatory regardless of the polarity. With the RCathode configuration, the stimulated cycle was prolonged compared with the control cycle at both 1 and 1.5 T, due to prolonged left SOL and TA EMG bursts, but no change was observed in right SOL and TA. With LCathode, GVS did not modify the cycle duration. Conclusion: During gait, a brief, low-intensity GVS pulse delivered at the right stance onset induced mainly long-latency polarity-dependent responses. Furthermore, a RCathode configuration increased the duration of the stimulated gait cycle by prolonging EMG activity on the anodic side. A similar approach could be explored to influence gait symmetry in individuals with neurological impairment.

Does higher knee hyperextension in patients with hemiplegia affect lateral and medial meniscus volume in the paretic leg? A cross-sectional study

BACKGROUND

After stroke, an abnormal gait pattern gradually leads to knee pain and joint lesions, resulting the gait instability. However, the correlation between the knee hyperextension and gait pattern, the meniscus volume, and the water content of meniscus in paretic and non-paretic legs has not been fully investigated. Moreover, most of physicians tend to ignore this knee hyperextension. This study attempted to emphasize the importance of knee hyperextension using gait analysis and Magnetic resonance imaging (Trial registration number ChiCTR2000039641, date of registration 04/11/2020).

METHODS

Eight patients with chronic hemiplegic (6 male, 2 female) volunteered to participate in this study. Participants was recruited if they had a hemiplegia following a stroke occurring more than 6 months, had an ability to walk 10 m without aids, had a Function Ambulation Category level at least 3 and above, and had a hemiplegic lower extremity identified as Brunnstrom state III or above identification. The spatial-temporal gait parameters and kinematic parameters in the paretic and the non-paretic legs and the percentage of free water content in deep and shallow layers.

RESULTS

Longer time since hemiplegia led to larger angles of knee hyperextension (R = 0.56, p = 0.016), larger angles of knee hyperextension led to more tears in meniscus (R =  - 0.53, - 0,57 and - 0.70), and larger angles of knee hyperextension decreased water content of the lateral meniscus in the non-paretic leg (R =  - 0.91) but increased water content of the medial meniscus (R = 0.53 and 0.63).

CONCLUSIONS

The knee hyperextension could not be ignored by physicians and needed to be diagnosed and treated as early as possible, the time since hemiplegia could be an indicator of sign of knee hyperextension.

Psychometric Evaluation of the Narrow Corridor Walk Test (NCWT) on Advanced Walking Balance in People with Stroke

Objectives. To investigate (i) the interrater and test-retest reliabilities of completion time and number of steps in the Narrow Corridor Walking Test (NCWT); (ii) the minimal detectable changes (MDCs) in NCWT results; (iii) the correlations between NCWT results and stroke-specific outcome measures; and (iv) the optimal cut-off values of NCWT results for discriminating the difference in advanced balance ability between people with stroke and healthy older adults. Design. Cross-sectional. Subjects. Thirty people with stroke and 30 healthy older adults. Methods. People with stroke completed the NCWT on two separate days with a 7- to 10-day interval. The Fugl-Meyer Assessment (FMA), ankle dorsiflexor and plantarflexor muscle strength, Berg Balance Scale (BBS), Timed Up and Go (TUG) test, and the Chinese version of the Community Integration Measure (CIM) were used to assess. The healthy older adults completed the NCWT once. Results. The NCWT completion time and NCWT steps showed excellent interrater reliability and test-retest reliability and significant correlations with FMA, affected ankle dorsiflexor muscle strength, BBS score, and TUG completion time. A cut-off value of 7.40 s for NCWT completion time and 13.33 for the NCWT steps distinguished people with stroke from healthy older adults. The MDCs of the NCWT completion time and NCWT steps were 6.87 s and 5.50, respectively. Conclusion. The NCWT is a reliable clinical measurement tool for the assessment of advanced balance ability in people with stroke.

A unilateral robotic knee exoskeleton to assess the role of natural gait assistance in hemiparetic patients

Background

Hemiparetic gait is characterized by strong asymmetries that can severely affect the quality of life of stroke survivors. This type of asymmetry is due to motor deficits in the paretic leg and the resulting compensations in the nonparetic limb. In this study, we aimed to evaluate the effect of actively promoting gait symmetry in hemiparetic patients by assessing the behavior of both paretic and nonparetic lower limbs. This paper introduces the design and validation of the REFLEX prototype, a unilateral active knee–ankle–foot orthosis designed and developed to naturally assist the paretic limbs of hemiparetic patients during gait.

Methods

REFLEX uses an adaptive frequency oscillator to estimate the continuous gait phase of the nonparetic limb. Based on this estimation, the device synchronically assists the paretic leg following two different control strategies: (1) replicating the movement of the nonparetic leg or (2) inducing a healthy gait pattern for the paretic leg. Technical validation of the system was implemented on three healthy subjects, while the effect of the generated assistance was assessed in three stroke patients. The effects of this assistance were evaluated in terms of interlimb symmetry with respect to spatiotemporal gait parameters such as step length or time, as well as the similarity between the joint’s motion in both legs.

Results

Preliminary results proved the feasibility of the REFLEX prototype to assist gait by reinforcing symmetry. They also pointed out that the assistance of the paretic leg resulted in a decrease in the compensatory strategies developed by the nonparetic limb to achieve a functional gait. Notably, better results were attained when the assistance was provided according to a standard healthy pattern, which initially might suppose a lower symmetry but enabled a healthier evolution of the motion of the nonparetic limb.

Conclusions

This work presents the preliminary validation of the REFLEX prototype, a unilateral knee exoskeleton for gait assistance in hemiparetic patients. The experimental results indicate that assisting the paretic leg of a hemiparetic patient based on the movement of their nonparetic leg is a valuable strategy for reducing the compensatory mechanisms developed by the nonparetic limb.

Serial Backward Locomotor Treadmill Training Improves Bidirectional Walking Performance in Chronic Stroke

Background and Research Question

Walking impairment remains a major limitation to functional independence after stroke. Yet, comprehensive and effective strategies to improve walking function after stroke are presently limited. Backward Locomotor Treadmill Training (BLTT) is a promising training approach for improving walking function; however, little is known about its mechanism of effect or the relationship between backward walking training and resulting overground forward walking performance. This study aims to determine the effects of serial BLTT on spatial aspects of backward and forward walking in chronic post-stroke individuals with residual walking impairment.

Methods

Thirty-nine adults (>6 months post-stroke) underwent 6 days of BLTT (3 × /week) over 2 weeks. Outcome measures included PRE-POST changes in backward and forward walking speeds, paretic and non-paretic step lengths, and single-support center of pressure distances. To determine the association between BLTT and overground walking, correlation analyses comparing training-related changes in these variables were performed.

Results

We report an overall improvement in BLTT and overground walking speeds, bilateral step lengths, and single-support center of pressure distances over six training sessions. Further, there were weak positive associations between PRE-POST changes in BLTT speed, BLTT paretic step length, and overground forward walking speed.

Conclusion and Significance

Our findings suggest that individuals with chronic post-stroke walking impairment experience improvements in spatial walking measures during BLTT and overground. Therefore, BLTT may be a potential adjunctive training approach for post-stroke walking rehabilitation.

Effect of cycling exercise on motor excitability and gait abnormalities in stroke patients

Background

The concepts of brain excitability are still re-wiring in response to changes in environment. Ambulation is often limited in stroke patients.

Objective

To determine the effect of cycling exercise on motor excitability and consequences on spatiotemporal gait parameters in stroke patients.

Methods

Forty male ischemic stroke patients were included; their age ranged from 45 to 60 years. The patients were assigned into two equal groups: control group (GI) and study group (GII). The GI is treated by a design physical therapy program in the form of task-oriented progressive resistance exercise for lower limb muscles, and the GII is treated by the same program in addition to cycling exercise for 30 min. Treatment was conducted three times per week for 10 weeks. The excitability over motor area (Cz) was assessed by the quantitative electroencephalogram (QEEG). The spatiotemporal gait parameters were assessed by the Biodex Gait Trainer 2TM.

Results

There was a significant increase of speed, step cycle, and step length of the affected side (P < 0.05) and a non-significant difference of step length of the non-affected side in the study group compared with that of the control group (P > 0.05). There was a significant increase of excitability over motor area (Cz) in the study group compared with that of the control group (P < 0.05).

Conclusion

Cycling exercise has a positive effect on excitability over motor area of lower limbs and can improve gait parameters in stroke patients.

BCI-Based Control for Ankle Exoskeleton T-FLEX: Comparison of Visual and Haptic Stimuli with Stroke Survivors

Brain–computer interface (BCI) remains an emerging tool that seeks to improve the patient interaction with the therapeutic mechanisms and to generate neuroplasticity progressively through neuromotor abilities. Motor imagery (MI) analysis is the most used paradigm based on the motor cortex’s electrical activity to detect movement intention. It has been shown that motor imagery mental practice with movement-associated stimuli may offer an effective strategy to facilitate motor recovery in brain injury patients. In this sense, this study aims to present the BCI associated with visual and haptic stimuli to facilitate MI generation and control the T-FLEX ankle exoskeleton. To achieve this, five post-stroke patients (55–63 years) were subjected to three different strategies using T-FLEX: stationary therapy (ST) without motor imagination, motor imagination with visual stimulation (MIV), and motor imagination with visual-haptic inducement (MIVH). The quantitative characterization of both BCI stimuli strategies was made through the motor imagery accuracy rate, the electroencephalographic (EEG) analysis during the MI active periods, the statistical analysis, and a subjective patient’s perception. The preliminary results demonstrated the viability of the BCI-controlled ankle exoskeleton system with the beta rebound, in terms of patient’s performance during MI active periods and satisfaction outcomes. Accuracy differences employing haptic stimulus were detected with an average of 68% compared with the 50.7% over only visual stimulus. However, the power spectral density (PSD) did not present changes in prominent activation of the MI band but presented significant variations in terms of laterality. In this way, visual and haptic stimuli improved the subject’s MI accuracy but did not generate differential brain activity over the affected hemisphere. Hence, long-term sessions with a more extensive sample and a more robust algorithm should be carried out to evaluate the impact of the proposed system on neuronal and motor evolution after stroke.

Analysis of Gait Motion Changes by Intervention Using Robot Suit Hybrid Assistive Limb (HAL) in Myelopathy Patients After Decompression Surgery for Ossification of Posterior Longitudinal Ligament

Ossification of the posterior longitudinal ligament (OPLL) is a hyperostonic condition in which the posterior longitudinal ligament becomes thick and loses its flexibility, resulting in ectopic ossification and severe neurologic deficit (Matsunaga and Sakou, 2012). It commonly presents with myelopathy and radiculopathy and with myelopathy progression motor disorders and balance disorders can appear. Even after appropriate surgical decompression, some motor impairments often remain. The Hybrid Assistive Limb (HAL) is a wearable powered suit designed to assist and support the user's voluntary control of hip and knee joint motion by detecting bioelectric signals from the skin surface and force/pressure sensors in the shoes during movement. In the current study, the HAL intervention was applied to 15 patients diagnosed with OPLL who presented with myelopathy after decompression surgery (6 acute and 9 chronic stage). Following the HAL intervention, there were significant improvements in gait speed, cadence, stride length, in both acute and chronic groups. Joint angle analysis of the lower limbs showed that range of motion (ROM) of hip and knee joints in acute group, and also ROM of hip joint and toe-lift during swing in chronic group increased significantly. ROM of knee joint became closer to healthy gait in both groups. Electromyography analysis showed that hamstrings activity in the late swing phase increased significantly for acute patients. Immidiate effect from HAL session was also observed. EMG of vastus medialis were decreased except chronic 7th session and EMG of gastrocnemius were decreased except acute 7th session, which suggests the patients were learning to walk with lesser knee-hypertension during the sessions. After all, double knee action appeared in both acute and chronic groups after the HAL intervention, rather than knee hyper-extension which is a common gait impairment in OPLL. We consider that these improvements lead to a smoother and healthier gait motion.

Gait training interventions for patients with stroke in India: A systematic review

BACKGROUND

Gait is considered to be the most important determinant of functional independence in activities of daily living. The challenges faced by stroke survivors in India differ from the western population due to economic, cultural, and geographical factors and this, in turn, may influence the choice of intervention. Hence, there is a need to understand the current gait training trends for stroke survivors in low resource settings like India.

RESEARCH QUESTION

To systematically review the literature on interventional strategies for improving gait among stroke survivors in India.

METHODS

Six databases were searched to identify RCTs delivering gait training to stroke survivors having some gait deficits in terms of speed or any other kinematic parameters. Studies of the English language from India were included. Two independent reviewers screened, extracted data, and assessed the study quality. A descriptive synthesis was undertaken and the data was summarized.

RESULTS

Of 2112 potentially relevant articles, 12 studies with a total of 412 participants were included after title, abstract and full-text screening. Studies tested the efficacy of interventions such as mirror therapy, motor imagery, transcutaneous electrical nerve stimulation, strengthening, and task-based training. The outcome measures were kinematic gait-analysis, gait velocity, Functional Ambulation Categories, Timed Up and Go, Fugl-Meyer Assessment. From the results of this review, active task-based gait training and strengthening along with motor priming seems to be the most tested interventions. Future studies may need to design interventions targeting both impairment and function to bring about maximum improvement in gait after stroke.

SIGNIFICANCE

Reviews addressing gait practices in developing countries for people with stroke are scarce. The present review would assist physiotherapists in developing countries to utilize evidence-based criteria for the selection of gait training approaches post-stroke. Due to the environmental and contextual demands, the effect of interventions for recovery among stroke survivors should be improvised in low resource settings. This review can be a source of recommendation in giving effective strategies for clinical practice.

Replacing canes with an elasticated orthotic-garment in chronic stroke patients - The influence on gait and balance. A series of N-of-1 trials

OBJECTIVE

To investigate the effect of replacing canes with an elasticated orthotic-garment on balance and gait-function in chronic stroke survivors.

DESIGN

Experimental, N-of-1 series with a replicated, ABC design with randomised phase duration in a home setting.

PARTICIPANTS

Four cane using chronic stroke survivors (P1-4).

INTERVENTIONS

Phase A (9-12 weeks) cane-walking "as usual" to establish baseline values; Phase B (9-16 weeks) intervention: orthotic-garment worn throughout the day with maximal cane-use reduction; Phase C (9-10 weeks) participant-determined follow-up: either no walking-aid, orthotic-garment or cane.

OUTCOME MEASURES

Primary: Functional-Gait-Assessment (FGA), Secondary: Trunk-sway during walking measured as Total-Angle-Area (TAA°²) in frontal and sagittal-planes, both measured weekly.

RESULTS

Visual and statistical analysis of results showed significant improvements in FGA from phase A to B in all participants. Improvement continued in phase C in P2, stabilized in P1 and P4 and deteriorated in P3. A Minimal-Clinical-Important-Difference of 6 points-change was achieved in P2 & P4. Trunk-sway reduced during walking, indicating increased stability, in two participants from phase A to B and in three participants from A to C but no TAA changes were statistically significant. In phase C participant-selected walking-aids were: P1 cane-usage reduced by 25%, P2 independent-walking with no assistive-device, S3 usual cane-usage, P4 orthotic-garment with reduced cane-usage 2-3 days-a-week, usual cane-usage 4-5 days.

CONCLUSIONS

Although walking ability is multifactorial these results indicate that the choice of walking-aids can have a specific and clinically relevant impact on gait following stroke. "Hands-free" assistive-devices may be more effective than canes in improving gait-function in some patients. CLINICALTRIALS.

GOV ID

NCT03642444.

Differences in Muscle Synergy Symmetry Between Subacute Post-stroke Patients With Bioelectrically-Controlled Exoskeleton Gait Training and Conventional Gait Training

Understanding the reorganization of the central nervous system after stroke is an important endeavor in order to design new therapies in gait training for stroke patients. Current clinical evaluation scores and gait velocity are insufficient to describe the state of the nervous system, and one aspect where this is lacking is in the quantification of gait symmetry. Previous studies have pointed out that spatiotemporal gait asymmetries are commonly observed in stroke patients with hemiparesis. Such asymmetries are known to cause long-term complications like joint pain and deformation. Recent studies also indicate that spatiotemporal measures showed that gait symmetry worsens after discharge from therapy. This study shows that muscle synergy analysis can be used to quantify gait symmetry and compliment clinical measures. Surface EMG was collected from lower limb muscles of subacute post-stroke patients (with an onset of around 14 days) from two groups, one undergoing robotic-assisted therapy (known as HAL group) and the other undergoing conventional therapy (known as Control group). Muscle synergies from the paretic and non-paretic limb were extracted with Non-Negative Matrix Factorization (NNMF) and compared with each other to obtain a gait symmetry index over therapy sessions. Gait events were tracked with motion tracking (for the HAL group) or foot pressure sensors (for the conventional therapy group). Patients from both groups were assessed over a 3-weeks long gait training program. Results indicated that there were no differences in muscle synergy symmetry for both groups of patients. However, the timing of muscle synergies were observed to be symmetrical in the HAL group, but not for the Control group. Intergroup comparisons of symmetry in muscle synergies and their timings were not significantly different. This could be due to a large variability in recovery in the Control group. Finally, stance time ratio was not observed to improve in both groups after their respective therapies. Interestingly, FIM and FMA scores of both groups were observed to improve after their respective therapies. Analysis of muscle coordination could reveal mechanisms of gait symmetry which could otherwise be difficult to observe with clinical scores.

Effects of two different types of ankle-foot orthoses on gait outcomes in patients with subacute stroke: a randomized crossover trial

OBJECTIVE

To identify whether patients in the subacute stage of stroke, with foot drop, would have better gait outcomes when using a double-adjustable AFO (DA AFO) or a posterior leaf spring AFO (PLS AFO) at baseline without practice and to determine whether one week of practice would significantly change gait outcomes with either of the AFOs.

DESIGN

Within-subject 2 × 2 repeated measures design.

SETTING

Postacute and outpatient rehabilitation center.

PARTICIPANTS

Twenty individuals with mean age of 57 years (SD: 12.0 years) with subacute stroke.

INTERVENTIONS

Participants were measured using DA AFO and PLS AFO at baseline. Follow-up measurements were taken after one week of practice with each type of AFO in randomly assigned order.

OUTCOME MEASURES

Gait endurance (6-Minute Walk Test (6MWT)), gait symmetry, and gait velocity at self-selected and fast-paced velocity measured using GAITRite gait analysis system and patient report of AFO preference.

RESULTS

At baseline, no significant differences were found between the 2 AFOs (P > 0.05). There was no significant interaction (P > 0.05) of AFO and practice for gait endurance, symmetry, and velocity. Main effect of practice was significant for gait endurance (P < 0.001), self-selected velocity (P = 0.001), and fast-paced velocity (P < 0.001). In all, 16 participants preferred using DA AFO for walking.

CONCLUSIONS

No difference between DA AFO and PLS AFO was found on measures of gait endurance, symmetry, and velocity at baseline or after practice. With practice over time, participants improved in gait endurance and velocity regardless of AFO type.

Functional outcome of stroke inpatients according to human immunodeficiency virus status: A feasibility study

Background

Stroke in human immunodeficiency virus positive (HIV+) individuals is becoming an increasing concern. Being significantly younger than typical stroke patients, the impact of functional challenges on quality of life and burden on society becomes more eminent.

Objectives

This feasibility study aims to determine the requirements for a large descriptive cohort, to adequately describe the functional outcome of stroke patients with varying HIV status.

Method

All stroke patients meeting the inclusion criteria were recruited over a 6-month period at a South African inpatient rehabilitation centre. Data were collected on admission and discharge using outcome measures including the Barthel Index (BI), Berg Balance Scale (BBS) and the use of assistive devices used to describe independence with activities of daily living (ADL), mobility and safety post-stroke. Statistical analysis was performed using Stata version 14.2.

Results

The feasibility study identified appropriate procedures and barriers to a successful study in addition to describing preliminary data on participant demographics, relevant medical history and functional outcomes post-stroke. Limitations that affected feasibility included minimal recruitment sites, length of data collection period, timely communication of participant discharge plans and dates, and confirmation of participant HIV status. An appropriate comparison between sub-groups could not be made because of disproportionate group sizes, median age differences and no assessor blinding.

Conclusion

To increase generalisability and the understanding of the unique HIV+ stroke profile, multiple recruitment sites, longer data collection periods, assessor blinding and age-matched groups with HIV status confirmation are recommended.

Enriching footsteps sounds in gait rehabilitation in chronic stroke patients: a pilot study

In the context of neurorehabilitation, sound is being increasingly applied for facilitating sensorimotor learning. In this study, we aimed to test the potential value of auditory stimulation for improving gait in chronic stroke patients by inducing alterations of the frequency spectra of walking sounds via a sound system that selectively amplifies and equalizes the signal in order to produce distorted auditory feedback. Twenty-two patients with lower extremity paresis were exposed to real-time alterations of their footstep sounds while walking. Changes in body perception, emotion, and gait were quantified. Our results suggest that by altering footsteps sounds, several gait parameters can be modified in terms of left-right foot asymmetry. We observed that augmenting low-frequency bands or amplifying the natural walking sounds led to a reduction in the asymmetry index of stance and stride times, whereas it inverted the asymmetry pattern in heel-ground exerted force. By contrast, augmenting high-frequency bands led to opposite results. These gait changes might be related to updating of internal forward models, signaling the need for adjustment of the motor system to reduce the perceived discrepancies between predicted-actual sensory feedbacks. Our findings may have the potential to enhance gait awareness in stroke patients and other clinical conditions, supporting gait rehabilitation.

The effect of aquatic and treadmill exercise in individuals with chronic stroke

ABSTRACT We compared the effect of gait training on treadmill versus deep water on balance and gait in 12 ischemic stroke chronic survivors randomly sorted to the Pool or Treadmill Groups. Berg Scale (BBS) and timed up and go test (TUG) were applied before and after the interventions. Just one person applied all tests and she was blinded for the aims of the study. Surface EMG of the paretic and non-paretic (NP) side muscles were recorded during walking on a treadmill. Three 100-ms epochs were extracted from the EMG related to gait phases: weight acceptance; propulsion; and pre-strike. For each epoch, we calculated the RMS of the EMG signal. Participants did gait training for 9 weeks (3 times/week, 40 minutes/session). The Pool group did the deep-water walking with a swimming belt. The Treadmill group walked on the treadmill at the maximum speed they could stand. The Manova group compared the effect of training, group, side, muscles, and gait phase into the EMG. Anova was used to test the effect of training, group side, and gait phase into BBS, TUG and EMG variables. Pool and Treadmill had increased balance and agility. The highest EMG RMS occurred at the paretic side, for the Treadmill and after training. The mm. tibialis anterior, gastrocnemius lateralis, vastus lateralis, and biceps femoris presented the highest RMS for the NP side; while for mm. rectus femoris and semitendinosus, the paretic side presented the highest RMS. Thus, the both types of exercise lead to similar functional adaptations with different muscular activations during walking.

Computational Design of FastFES Treatment to Improve Propulsive Force Symmetry During Post-stroke Gait: A Feasibility Study

Stroke is a leading cause of long-term disability worldwide and often impairs walking ability. To improve recovery of walking function post-stroke, researchers have investigated the use of treatments such as fast functional electrical stimulation (FastFES). During FastFES treatments, individuals post-stroke walk on a treadmill at their fastest comfortable speed while electrical stimulation is delivered to two muscles of the paretic ankle, ideally to improve paretic leg propulsion and toe clearance. However, muscle selection and stimulation timing are currently standardized based on clinical intuition and a one-size-fits-all approach, which may explain in part why some patients respond to FastFES training while others do not. This study explores how personalized neuromusculoskeletal models could potentially be used to enable individual-specific selection of target muscles and stimulation timing to address unique functional limitations of individual patients post-stroke. Treadmill gait data, including EMG, surface marker positions, and ground reactions, were collected from an individual post-stroke who was a non-responder to FastFES treatment. The patient's gait data were used to personalize key aspects of a full-body neuromusculoskeletal walking model, including lower-body joint functional axes, lower-body muscle force generating properties, deformable foot-ground contact properties, and paretic and non-paretic leg neural control properties. The personalized model was utilized within a direct collocation optimal control framework to reproduce the patient's unstimulated treadmill gait data (verification problem) and to generate three stimulated walking predictions that sought to minimize inter-limb propulsive force asymmetry (prediction problems). The three predictions used: (1) Standard muscle selection (gastrocnemius and tibialis anterior) with standard stimulation timing, (2) Standard muscle selection with optimized stimulation timing, and (3) Optimized muscle selection (soleus and semimembranosus) with optimized stimulation timing. Relative to unstimulated walking, the optimal control problems predicted a 41% reduction in propulsive force asymmetry for scenario (1), a 45% reduction for scenario (2), and a 64% reduction for scenario (3), suggesting that non-standard muscle selection may be superior for this patient. Despite these predicted improvements, kinematic symmetry was not noticeably improved for any of the walking predictions. These results suggest that personalized neuromusculoskeletal models may be able to predict personalized FastFES training prescriptions that could improve propulsive force symmetry, though inclusion of kinematic requirements would be necessary to improve kinematic symmetry as well.

Post-stroke Visual Gait Measure for Developing Countries: A Reliability and Validity Study

Background

Visual gait assessment is a cost-effective clinical method to assess post-stroke gait deviations. The Rivermead Visual Gait Assessment (RVGA) is a one such measure that assesses the kinematic aspect of the gait deviations in stroke. However, the available information on psycho-clinocometric properties of the measure is not adequate.

Objective

To establish reliability and validity of RVGA using walking-videos of the post-stroke subjects.

Methods

Design: Observational study.

Setting

A rehabilitation institute Participants: A convenience sample of 40 chronic stroke patients.

Outcome Measures

RVGA, Fugl-Meyer assessment (lower extremity), 10-m walk test, Time up and go test, and Berg balance scale (BBS).

Procedure

Walking was video-taped from the anterior aspect, posterior aspect, affected side, and less-affected side. After coding the tapes, a research staff member provided them to four different raters in a random order. Each rater scored the coded video on the RVGA data collection sheet twice: one at the baseline and another after 1 month to eliminate any recollection of the initial assessment.

Results

The findings exhibit that there was good-to-excellent agreement between the scores of the raters and also between the assessments (correlation coefficient = 0.94 to 0.95; P < 0.001). The measure also exhibits acceptable validity when correlated with scores of BBS (r = 0.4; P < 0.001).

Conclusion

Video-based RVGA is a reliable and valid tool to assess gait-related impairment in post-stroke hemiparesis. This cost-effective measure may be incorporated in the clinical and research practice to discern and quantify complex phenomenon of the gait deviation. RVGA may be considered as a useful tool, especially in developing countries where expensive gait analyzer is usually not available.

The regularity of orthosis use and the reasons for disuse in stroke patients

This is a Retrospective descriptive study. Orthoses and walking aids are used frequently in stroke rehabilitation to facilitate ambulation. The aim was to describe the regularity of orthosis use and the reasons for disuse in stroke after discharge from inpatient rehabilitation. The study included 64 (43 men, 21 women) subacute stroke patients who had been discharged from our clinic in the last 6 months. Demographic and clinical findings, proposed orthoses and walking aids, frequency of usage for the proposed orthoses, reasons for disuse, and the ambulation levels were recorded. A total of 54 (84.4%) patients had an ankle-foot orthosis and 10 (15.6%) patients had a knee-ankle-foot orthosis. The orthosis frequency of use was every day in 38 (59.4%) patients and one to seven times a week in seven (10.9%) patients, whereas 19 (29.7%) did not use them. The reasons for orthosis disuse were finding them unnecessary in seven (27%) patients, usage difficulties in six (23%) patients, pressure sensation in five (19.2%) patients, the belief that they did not make life easier in five (19.2%) patients, lack of a suitable environment in one (3.8%) patient, orthosis wear in one (3.8%) patient, and systemic disease in one (3.8%) patient. Age, sex, residence, the disease duration, and recommended orthosis duration (how long the prescribed orthosis was used), recommended orthosis, range of motion limitation in the lower extremities, presence of spasticity, type of orthosis, and the ambulation level were not statistically significantly associated with the frequency of orthosis use (P>0.05). The only significant clinical factor for the frequency of orthosis use was the lower extremity Brunnstrom neurophysiological recovery stage (P<0.008). Orthosis use had been discontinued by 29% of the patients. The most common reasons reported for discontinuing orthosis use were that the patients found it unnecessary, usage difficulty, pressure sensation, not making life easier, lack of a suitable environment, and orthosis wear. The only significant clinical factor for the frequency of orthosis use was the lower extremity Brunnstrom neurophysiological recovery stage.

Reshaping of Bilateral Gait Coordination in Hemiparetic Stroke Patients After Early Robotic Intervention

Hemiparetic gait is a common condition after stroke which alters importantly the quality of life of stroke survivors. In recent years, several robotic interventions have been developed to support and enhance rehabilitation strategies for such population. The Hybrid Assistive Limb^® (HAL) robot suit is a unique device able to collect in real time bioelectric signals from the patient to support and enhance voluntary gait. HAL has been used before in early stages of stroke showing gait improvement after the intervention. However, evaluation of the coordination of gait has not been done yet. Coordination is a key factor for an adequate gait performance; consequently, its changes may be closely related to gait recovery. In this study, we used planar covariation to evaluate coordination changes in hemiparetic stroke patients after early HAL intervention. Before starting, impaired intersegmental coordination for the paretic and non-paretic side was evident. HAL intervention was able to induce recovery of the covariation loop shape and deviation from the covariation plane improving intersegmental coordination. Also, there was a tendency of recovery for movement range evidenced by comparison of peak elevation angles of each limb segment of the patients before and after HAL intervention, and also when compared to healthy volunteers. Our results suggest that early HAL intervention contributed to the improvement of gait coordination in hemiparetic stroke patients by reinforcing central pattern generators and therefore reshaping their gait pattern. Trial registration: UMIN000022410 2016/05/23.

Effect of postural insoles on gait pattern in individuals with hemiparesis: A randomized controlled clinical trial

INTRODUCTION

Recovering the ability to walk is an important goal of physical therapy for patients who have survived cerebrovascular accident (stroke). Orthotics can provide a reduction in plantar flexion of the ankle, leading to greater stability in the stance phase of the gait cycle. Postural insoles can be used to reorganize the tone of muscle chains, which exerts an influence on postural control through correction reflexes. The aim of the present study was to perform kinematic and spatiotemporal analyses of gait in stroke survivors with hemiparesis during postural insole usage.

MATERIAL AND METHODS

Twenty stroke victims were randomly divided into two groups: 12 in the experimental group, who used insoles with corrective elements specifically designed for equinovarus foot, and eight in the control group, who used placebo insoles with no corrective elements. Both groups were also submitted to conventional physical therapy. The subjects were analyzed immediately following insole placement and after three months of insole usage. The SMART-D 140^® system (BTS Engineering) with eight cameras sensitive to infrared light and the 32-channel SMART-D INTEGRATED WORKSTATION^® were used for the three-dimensional gait evaluation.

RESULTS

Significant improvements were found in kinematic range of movement in the ankle and knee as well as gains in ankle dorsiflexion and knee flexion in the experimental group in comparison to the control group after three months of using the insoles.

CONCLUSION

Postural insoles offer significant benefits to stroke survivors regarding the kinematics of gait, as evidenced by gains in ankle dorsiflexion and knee flexion after three months of usage in combination with conventional physical therapy.

Post-stroke Hemiplegic Gait: New Perspective and Insights

Walking dysfunction occurs at a very high prevalence in stroke survivors. Human walking is a phenomenon often taken for granted, but it is mediated by complicated neural control mechanisms. The automatic process includes the brainstem descending pathways (RST and VST) and the intraspinal locomotor network. It is known that leg muscles are organized into modules to serve subtasks for body support, posture and locomotion. Major kinematic mechanisms are recognized to minimize the center of gravity (COG) displacement. Stroke leads to damage to motor cortices and their descending corticospinal tracts and subsequent muscle weakness. On the other hand, brainstem descending pathways and the intraspinal motor network are disinhibited and become hyperexcitable. Recent advances suggest that they mediate post-stroke spasticity and diffuse spastic synergistic activation. As a result of such changes, existing modules are simplified and merged, thus leading to poor body support and walking performance. The wide range and hierarchy of post-stroke hemiplegic gait impairments is a reflection of mechanical consequences of muscle weakness, spasticity, abnormal synergistic activation and their interactions. Given the role of brainstem descending pathways in body support and locomotion and post-stroke spasticity, a new perspective of understanding post-stroke hemiplegic gait is proposed. Its clinical implications for management of hemiplegic gait are discussed. Two cases are presented as clinical application examples.

Lateral Symmetry of Synergies in Lower Limb Muscles of Acute Post-stroke Patients After Robotic Intervention

Gait disturbance is commonly associated with stroke, which is a serious neurological disease. With current technology, various exoskeletons have been developed to provide therapy, leading to many studies evaluating the use of such exoskeletons as an intervention tool. Although these studies report improvements in patients who had undergone robotic intervention, they are usually reported with clinical assessment, which are unable to characterize how muscle activations change in patients after robotic intervention. We believe that muscle activations can provide an objective view on gait performance of patients. To quantify improvement of lateral symmetry before and after robotic intervention, muscle synergy analysis with Non-Negative Matrix Factorization was used to evaluate patients' EMG data. Eight stroke patients in their acute phase were evaluated before and after a course of robotic intervention with the Hybrid Assistive Limb (HAL), lasting over 3 weeks. We found a significant increase in similarity between lateral synergies of patients after robotic intervention. This is associated with significant improvements in gait measures like walking speed, step cadence, stance duration percentage of gait cycle. Clinical assessments [Functional Independence Measure-Locomotion (FIM-Locomotion), FIM-Motor (General), and Fugl-Meyer Assessment-Lower Extremity (FMA-LE)] showed significant improvements as well. Our study shows that muscle synergy analysis can be a good tool to quantify the change in neuromuscular coordination of lateral symmetry during walking in stroke patients.

Factors Leading to Improved Gait Function in Patients with Subacute or Chronic Central Nervous System Impairments Who Receive Functional Training with the Robot Suit Hybrid Assistive Limb

The factors that lead to the improvement of gait function in patients with diseases of the central nervous system (CNS) who use a hybrid assistive limb (HAL) are not yet fully understood. The purpose of the present study was to analyze these factors to determine the prognosis of the patients' gait function. Patients whose CNS disease was within 180 days since onset were designated as the subacute-phase patients, and patients whose disease onset had occurred more than 180 days previously were designated as chronic-phase patients. Fifteen subacute-phase patients and 15 chronic-phase patients were given HAL training. The study analyzed how post-training walking independence in these patients was affected by the following factors: age, disease, lesion area, lower limb function, balance, period until the start of training, number of training sessions, additional rehabilitation, higher-order cognitive dysfunction, HAL model, and the use of a non-weight-bearing walking-aid. In subacute-phase patients, walking independence was related to lower limb function (r_s = 0.35). In chronic-phase patients, there was a statistically significant correlation between post-training walking independence and balance (r_s = 0.78). In addition, in patients with a severe motor dysfunction that was accompanied by inattention and global cognitive dysfunction, little improvement occurred, even with double-leg model training, because they had difficulty wearing the device. The results demonstrated that the factors that improved walking independence post HAL training differed between patients with subacute- and chronic-stage CNS diseases. The findings may serve as valuable information for future HAL training of patients with CNS diseases.

Combining muscle synergies and biomechanical analysis to assess gait in stroke patients

The understanding of biomechanical deficits and impaired neural control of gait after stroke is crucial to prescribe effective customized treatments aimed at improving walking function. Instrumented gait analysis has been increasingly integrated into the clinical practice to enhance precision and inter-rater reliability for the assessment of pathological gait. On the other hand, the analysis of muscle synergies has gained relevance as a novel tool to describe the neural control of walking. Since muscle synergies and gait analysis capture different but equally important aspects of walking, we hypothesized that their combination can improve the current clinical tools for the assessment of walking performance. To test this hypothesis, we performed a complete bilateral, lower limb biomechanical and muscle synergies analysis on nine poststroke hemiparetic patients during overground walking. Using stepwise multiple regression, we identified a number of kinematic, kinetic, spatiotemporal and synergy-related features from the paretic and non-paretic side that, combined together, allow to predict impaired walking function better than the Fugl-Meyer Assessment score. These variables were time of peak knee flexion, VAF_total values, duration of stance phase, peak of paretic propulsion and range of hip flexion. Since these five variables describe important biomechanical and neural control features underlying walking deficits poststroke, they may be feasible to drive customized rehabilitation therapies aimed to improve walking function. This paper demonstrates the feasibility of combining biomechanical and neural-related measures to assess locomotion performance in neurologically injured individuals.

Boosting the traditional physiotherapist approach for stroke spasticity using a sensorized ankle foot orthosis: a pilot study

BACKGROUND

Spasticity is a motor disorder that is commonly treated manually by a physical therapist (PhT) stretching the muscles. Recent data on learning have demonstrated the importance of human-to-human interaction in improving rehabilitation: cooperative motor behavior engages specific areas of the motor system compared with execution of a task alone.

OBJECTIVES

We hypothesize that PhT-guided therapy that involves active collaboration with the patient (Pt) through shared biomechanical visual biofeedback (vBFB) positively impacts learning and performance by the Pt during ankle spasticity treatment. A sensorized ankle foot orthosis (AFO) was developed to provide online quantitative data of joint range of motion (ROM), angular velocity, and electromyographic activity to the PhT and Pt during the treatment of ankle spasticity.

METHODS

Randomized controlled clinical trial. Ten subacute stroke inpatients, randomized into experimental (EXP) and control (CTRL) groups, underwent six weeks of daily treatment. The EXP group was treated with an active AFO, and the CTRL group was given an inactive AFO. Spasticity, ankle ROM, ankle active and passive joint speed, and coactivation index (CI) were assessed at enrollment and after 15-30 sessions.

RESULTS

Spasticity and CI (p < 0.005) decreased significantly after training only in the EXP group, in association with a significant rise in active joint speed and active ROM (p < 0.05). Improvements in spasticity (p < 0.05), active joint speed (p < 0.001), and CI (p < 0.001) after treatment differed between the EXP and CTRL groups.

CONCLUSIONS

PhT-Pt sharing of exercise information, provided by joint sensorization and vBFB, improved the efficacy of the conventional approach for treating ankle spasticity in subacute stroke Pts.

Role of ankle foot orthosis in improving locomotion and functional recovery in patients with stroke: A prospective rehabilitation study

OBJECTIVE

To study role of ankle foot orthosis (AFO) in improving locomotion and functional recovery after stroke.

SETTING

Neurological Rehabilitation Department of a university research tertiary hospital.

PATIENTS AND METHODS

AFO and activity based rehabilitation.

MAIN OUTCOME MEASURES

Distance (meters) covered during the 6-minute walk test (6MWT) and speed (meter/second) during the 10-meter walk test. Functional abilities assessed using Functional Independence Measure (FIM®).

RESULTS

Twenty-six patients (21 male) with stroke (mean duration 196.7 days, range 45-360 days) and mean age of 41.6 years (range 18-65 years, standard deviation [SD] 12.5) were included. Fourteen had right hemiplegia. The mean length of stay in the unit was 26.5 days (range 18-45 days, SD 5.5). All patients had equinus deformity with spastic foot drop and were provided with AFO. Walking endurance with 6MWT was 90 m on admission (without AFO). At discharge, it improved to 174 m with AFO and 121 m without AFOs (P < 0.001-with and without AFO at discharge). Walking speed improved from 0.4 m/s (admission) to 0.51 m/s with AFO, P = 0.004 and 0.45 m/s without AFO, P = 0.015) at discharge. Nine patients (34.6%) had clinically important difference-minimal clinically important difference (>0.16 m/s speed gain; >50 m endurance gain) at discharge. The mean FIM® score on admission was 84.3 ± 18.6. At discharge FIM® improved to 101.9 ± 13.7 (P < 0.001).

CONCLUSIONS

Use of AFOs improve gait parameters significantly in only one-third stroke patients in the study when combined with activity-based inpatient-rehabilitation.

Effects of Balance Control Training on Functional Outcomes in Subacute Hemiparetic Stroke Patients

OBJECTIVE

To investigate the efficacy of balance control training using a newly developed balance control trainer (BalPro) on the balance and gait of patients with subacute hemiparetic stroke.

METHODS

Forty-three subacute stroke patients were assigned to either a balance control training (BCT) group or a control group. The BCT group (n=23) was trained with BalPro for 30 minutes a day, 5 days a week for 2 weeks, and received one daily session of conventional physical therapy. The control group (n=20) received two sessions of conventional physical therapy every day for 2 weeks. The primary outcome was assessment with the Berg Balance Scale (BBS). Secondary outcomes were Functional Ambulation Category (FAC), the 6-minute walking test (6mWT), Timed Up and Go (TUG), the Korean version of Modified Barthel Index (K-MBI), and the manual muscle test (MMT) of the knee extensor. All outcome measures were evaluated before and after 2 weeks of training in both groups.

RESULTS

There were statistically significant improvements in all parameters except MMT and FAC after 2 weeks of treatment in both groups. After training, the BCT group showed greater improvements in the BBS and the 6mWT than did the control group.

CONCLUSION

Balance control training using BalPro could be a useful treatment for improving balance and gait in subacute hemiparetic stroke patients.

Does stroke location predict walk speed response to gait rehabilitation?

OBJECTIVES

Recovery of independent ambulation after stroke is a major goal. However, which rehabilitation regimen best benefits each individual is unknown and decisions are currently made on a subjective basis. Predictors of response to specific therapies would guide the type of therapy most appropriate for each patient. Although lesion topography is a strong predictor of upper limb response, walking involves more distributed functions. Earlier studies that assessed the cortico-spinal tract (CST) were negative, suggesting other structures may be important.

EXPERIMENTAL DESIGN

The relationship between lesion topography and response of walking speed to standard rehabilitation was assessed in 50 adult-onset patients using both volumetric measurement of CST lesion load and voxel-based lesion-symptom mapping (VLSM) to assess non-CST structures. Two functional mobility scales, the functional ambulation category (FAC) and the modified rivermead mobility index (MRMI) were also administered. Performance measures were obtained both at entry into the study (3-42 days post-stroke) and at the end of a 6-week course of therapy. Baseline score, age, time since stroke onset and white matter hyperintensities score were included as nuisance covariates in regression models.

PRINCIPAL OBSERVATIONS

CST damage independently predicted response to therapy for FAC and MRMI, but not for walk speed. However, using VLSM the latter was predicted by damage to the putamen, insula, external capsule and neighbouring white matter.

CONCLUSIONS

Walk speed response to rehabilitation was affected by damage involving the putamen and neighbouring structures but not the CST, while the latter had modest but significant impact on everyday functions of general mobility and gait. Hum Brain Mapp 37:689-703, 2016. © 2015 Wiley Periodicals, Inc.

Reliability and validity of the sideways step test and its correlation with motor function after stroke

[Purpose] This study investigated the intra-rater, inter-rater and test-retest reliability of the sideways step test (SST), its correlation with other indicators of stroke-specific impairment, and the cut-off count best discriminating subjects with stroke from their healthy counterparts. [Subjects and Methods] Forty-three subjects with chronic stroke and 41 healthy subjects older than 50 years participated in this study. The SST was administered along with the Fugl-Meyer motor assessment for the lower extremities (FMA-LE), the five-times sit to stand (5TSTS) test, the Berg Balance Scale (BBS), the movement velocity (MVL) by the limits of stability (LOS) test, the ten-metre walk (10mW) test, the timed “Up and Go” (TUG) test and the Activities-specific Balance Confidence (ABC) scale. [Results] The SST showed good to excellent intra-rater, inter-rater and test-retest reliability. The SST counts correlated with 5TSTS times, 10mW times, TUG times, and the FMA-LE and BBS scores. SST counts of 11 for the paretic leg and 14 for the non-paretic leg were found to distinguish the healthy adults from subjects with stroke. [Conclusion] The sideways step test is a reliable clinical test, which correlates with the functional strength, gait speed, and functional balance of people with chronic stroke.

Interlimb Coordination During Step-to-Step Transition and Gait Performance

Most energy spent in walking is due to step-to-step transitions. During this phase, the interlimb coordination assumes a crucial role to meet the demands of postural and movement control. The authors review studies that have been carried out regarding the interlimb coordination during gait, as well as the basic biomechanical and neurophysiological principles of interlimb coordination. The knowledge gathered from these studies is useful for understanding step-to-step transition during gait from a motor control perspective and for interpreting walking impairments and inefficiency related to pathologies, such as stroke. This review shows that unimpaired walking is characterized by a consistent and reciprocal interlimb influence that is supported by biomechanical models, and spinal and supraspinal mechanisms. This interlimb coordination is perturbed in subjects with stroke.

Effect of Task Specific Exercises, Gait Training, and Visual Biofeedback on Equinovarus Gait among Individuals with Stroke: Randomized Controlled Study

Background and Purpose. Equinovarus foot is a common sign after stroke. The aim of this study is to investigate the effect of task specific exercises, gait training, and visual biofeedback on correcting equinovarus gait among individuals with stroke. Subjects and Methods. Sixteen subjects with ischemic stroke were randomly assigned to two equal groups (G1 and G2). All the patients were at stage 4 of motor recovery of foot according to Chedoke-McMaster Stroke Assessment without any cognitive dysfunction. E-med pedography was used to measure contact time, as well as force underneath hind and forefoot during walking. Outcome measures were collected before randomization, one week after the last session, and four weeks later. Participants in G1 received task specific exercises, gait training, and visual biofeedback and a traditional physical therapy program was applied for participants in G2 for 8 weeks. Results. Significant improvement was observed among G1 patients (P ≤ 0.05) which lasts one month after therapy termination. On the other hand, there were no significant differences between measurements of the participants in G2. Between groups comparison also revealed a significant improvement in G1 with long lasting effect. Conclusion. The results of this study showed a positive long lasting effect of the task specific exercises, gait training, and visual biofeedback on equinovarus gait pattern among individuals with stroke.

Kinematic gait analysis using inertial sensors with subjects after stroke in two different arteries

[Purpose] The aim of the present study was described the kinematic characteristics of gait in stroke patients with two different arteries involved. [Subjects and Methods] Two patients who had suffered a basilar (A) or middle (B) cerebral artery ischemic stroke were compared with a control (C). Seventeen inertial sensors were used with acquisition rate of 120 Hz. The participants walked 3 times on a 10 meter walkway. From the raw data, the three gait cycles from the middle of each trial were chosen and analyzed. [Results] During the stance phase, patients A and B had a lower hip angle at initial contact and maximum flexion angle during load response than the control. Patient A and the control subject had similar knee angle values at initial contact, and patient B presented a flexed position in the initial phase of the gait cycle. The maximum flexion angles during loading response were also higher for patient B. The sagittal plane excursion for the ankle joint was lower for patient B in comparison with the other subjects. [Conclusion] Differences during walking between patients who had stroke in different arteries may be related to an alternative compensatory strategy. Patient A and the control subject had similar gait cycle curves at all joints, while patient B showed a rigid synergic pattern.

Falls and Use of Assistive Devices in Stroke Patients with Hemiparesis: Association with Balance Ability and Fall Efficacy

PURPOSE

This study investigates balance ability and the fall efficacy with regard to the experiences of stroke patients with hemiparesis.

METHODS

The experience of falling, the use of assistive devices, and each disease-related characteristic were assessed using face-to-face interviews and a self-reported questionnaire. The Berg Balance Scale and Fall Efficacy Scale were used to measure balance ability and confidence.

RESULTS

The fall efficacy was significantly lower in participants who had experienced falls than those who had not. The participants who used assistive devices exhibited low balance ability and fall efficacy compared to those who did not use assistive devices.

CONCLUSIONS

Stroke patients with fall experience and walking aids might be considered at increased risk of falling.

CLINICAL RELEVANCE

Preventive measures for individuals using walking aids may be beneficial in reducing the fall rate of community-dwelling stroke patients.

Functional Data Analyses for the Assessment of Joint Power Profiles During Gait of Stroke Subjects

Lower extremity kinetic data during walking of 12 people with chronic poststroke were reanalyzed, using functional analysis of variance (FANOVA). To perform the FANOVA, the whole curve is represented by a mathematical function, which spans the whole gait cycle and avoids the need to identify isolated points, as required for traditional parametric analyses of variance (ANOVA). The power variables at the ankle, knee, and hip joints, in the sagittal plane, were compared between two conditions: With and without walking sticks at comfortable and fast speeds. For the ankle joint, FANOVA demonstrated increases in plantar flexion power generation during 60–80% of the gait cycle between fast and comfortable speeds with the use of walking sticks. For the knee joint, the use of walking sticks resulted in increases in the knee extension power generation during 10–30% of the gait cycle. During both speeds, the use of walking sticks resulted in increased power generation by the hip extensors and flexors during 10–30% and 40–70% of the gait cycle, respectively. These findings demonstrated the benefits of applying the FANOVA approach to improve the knowledge regarding the effects of walking sticks on gait biomechanics and encourage its use within other clinical contexts.

Gait disturbances in patients with stroke

Poststroke hemiplegic gait is a mixture of deviations and compensatory motion dictated by residual functions, and thus each patient must be examined and his/her unique gait pattern identified and documented. Quantitative 3-dimensional gait analysis is the best way to understand the complex multifactorial gait dysfunction in hemiparetic patients. The goals of the present work are to (1) review the temporospatial, kinematic, kinetic, and electromyographic deviations from normal gait that commonly occur after stroke and are of clinical significance, along with the most likely causes of these deviations, and (2) differentiate the departures from normal gait parameters that arise as a direct consequence of poststroke motor problems and those that arise as learned or adaptive compensations for poststroke motor problems.

Gait analysis in a pre- and post-ischemic stroke biomedical pig model

Severity of neural injury including stroke in human patients, as well as recovery from injury, can be assessed through changes in gait patterns of affected individuals. Similar quantification of motor function deficits has been measured in rodent animal models of such injuries. However, due to differences in fundamental structure of human and rodent brains, there is a need to develop a large animal model to facilitate treatment development for neurological conditions. Porcine brain structure is similar to that of humans, and therefore the pig may make a more clinically relevant animal model. The current study was undertaken to determine key gait characteristics in normal biomedical miniature pigs and dynamic changes that occur post-neural injury in a porcine middle cerebral artery (MCA) occlusion ischemic stroke model. Yucatan miniature pigs were trained to walk through a semi-circular track and were recorded with high speed cameras to detect changes in key gait parameters. Analysis of normal pigs showed overall symmetry in hindlimb swing and stance times, forelimb stance time, along with step length, step velocity, and maximum hoof height on both fore and hindlimbs. A subset of pigs were again recorded at 7, 5 and 3 days prior to MCA occlusion and then at 1, 3, 5, 7, 14 and 30 days following surgery. MRI analysis showed that MCA occlusion resulted in significant infarction. Gait analysis indicated that stroke resulted in notable asymmetries in both temporal and spatial variables. Pigs exhibited lower maximum front hoof height on the paretic side, as well as shorter swing time and longer stance time on the paretic hindlimb. These results support that gait analysis of stroke injury is a highly sensitive detection method for changes in gait parameters in pig.

Effect of Ankle-foot Orthosis on Gait Velocity and Cadence of Stroke Patients: A Systematic Review

[Purpose] The aim of the present study was to analyze the effect of an ankle-foot orthosis on gait variables (velocity and cadence) of stroke patients. To do this, a systematic review was conducted of four databases. [Subjects and Methods] The papers identified were evaluated based on the following inclusion criteria: 1) design: controlled, clinical trial; 2) population: stroke patients; 3) intervention: analysis of spatiotemporal variables of gait with an ankle-foot orthosis; 4) control group with different intervention or no intervention; and 5) outcome: improvement in gait velocity or cadence. [Results] Thirteen controlled trials addressing the effect of an ankle-foot orthosis on gait variables of stroke patients were found. They exhibited methodological quality of 3 or more points on the PEDro scale. [Conclusion] While the findings suggest the benefits of an AFO regarding gait velocity, the impact of this type of orthosis on cadence remains inconclusive. Thus, there is a need for further well-designed randomized, controlled, clinical trials to establish better scientific evidence for the effects of AFO usage on gait variables of stroke patients.

Rehabilitation with poststroke motor recovery: a review with a focus on neural plasticity

Motor recovery after stroke is related to neural plasticity, which involves developing new neuronal interconnections, acquiring new functions, and compensating for impairment. However, neural plasticity is impaired in the stroke-affected hemisphere. Therefore, it is important that motor recovery therapies facilitate neural plasticity to compensate for functional loss. Stroke rehabilitation programs should include meaningful, repetitive, intensive, and task-specific movement training in an enriched environment to promote neural plasticity and motor recovery. Various novel stroke rehabilitation techniques for motor recovery have been developed based on basic science and clinical studies of neural plasticity. However, the effectiveness of rehabilitative interventions among patients with stroke varies widely because the mechanisms underlying motor recovery are heterogeneous. Neurophysiological and neuroimaging studies have been developed to evaluate the heterogeneity of mechanisms underlying motor recovery for effective rehabilitation interventions after stroke. Here, we review novel stroke rehabilitation techniques associated with neural plasticity and discuss individualized strategies to identify appropriate therapeutic goals, prevent maladaptive plasticity, and maximize functional gain in patients with stroke.