Marco Iosa

Rehabilitation of gait after stroke: a review towards a top-down approach

This document provides a review of the techniques and therapies used in gait rehabilitation after stroke. It also examines the possible benefits of including assistive robotic devices and brain-computer interfaces in this field, according to a top-down approach, in which rehabilitation is driven by neural plasticity.The methods reviewed comprise classical gait rehabilitation techniques (neurophysiological and motor learning approaches), functional electrical stimulation (FES), robotic devices, and brain-computer interfaces (BCI).From the analysis of these approaches, we can draw the following conclusions. Regarding classical rehabilitation techniques, there is insufficient evidence to state that a particular approach is more effective in promoting gait recovery than other. Combination of different rehabilitation strategies seems to be more effective than over-ground gait training alone. Robotic devices need further research to show their suitability for walking training and their effects on over-ground gait. The use of FES combined with different walking retraining strategies has shown to result in improvements in hemiplegic gait. Reports on non-invasive BCIs for stroke recovery are limited to the rehabilitation of upper limbs; however, some works suggest that there might be a common mechanism which influences upper and lower limb recovery simultaneously, independently of the limb chosen for the rehabilitation therapy. Functional near infrared spectroscopy (fNIRS) enables researchers to detect signals from specific regions of the cortex during performance of motor activities for the development of future BCIs. Future research would make possible to analyze the impact of rehabilitation on brain plasticity, in order to adapt treatment resources to meet the needs of each patient and to optimize the recovery process.

Who May Benefit From Robotic-Assisted Gait Training? A Randomized Clinical Trial in Patients With Subacute Stroke

Background. Robotic-assisted walking training after stroke aims to enable highly impaired patients to walk independently, but results have been mixed. Objective. The authors aimed to identify the characteristics of patients who may be most likely to benefit. Methods. A total of 48 participants with motor and gait dysfunction following subacute stroke were stratified by the motricity index into high (<29) and low (≥29) motor impairment groups. Each arm was randomized to a robotic or control group (RG or CG) at a mean of 20 days after stroke. All patients underwent 2 therapy sessions per day, 5 days per week for 3 months. Those in the RG underwent 20 sessions of robotic-assisted gait training in the first 4 weeks of inpatient therapy using controlled endpoint trajectories and abbreviated conventional therapy, whereas the CG received only conventional gait training. The primary outcome was the functional ambulation category (FAC), and secondary measures were the Rivermead mobility index (RMI) and 6-minute walking distance, all evaluated at hospital admission and at discharge. Results. The lower motricity group assigned to an electromechanical device significantly improved in the FAC (P < .001), RMI (P = .001), and walking distance (P = .029). Conventional and robotic therapies were equivalent in the higher motricity arm. Conclusion. Robotic therapy combined with conventional therapy may be more effective than conventional therapy alone in patients with greater motor impairment during inpatient stroke rehabilitation.

Control of the upper body accelerations in young and elderly women during level walking

BackgroundThe control of the head movements during walking allows for the stabilisation of the optic flow, for a more effective processing of the vestibular system signals, and for the consequent control of equilibrium.In young individuals, the oscillations of the upper body during level walking are characterised by an attenuation of the linear acceleration going from pelvis to head level. In elderly subjects the ability to implement this motor strategy is reduced. The aim of this paper is to go deeper into the mechanisms through which the head accelerations are controlled during level walking, in both young and elderly women specifically.MethodsA stereophotogrammetric system was used to reconstruct the displacement of markers located at head, shoulder, and pelvis level while 16 young (age: 24 ± 4 years) and 20 older (age: 72 ± 4 years) female volunteers walked at comfortable and fast speed along a linear pathway. The harmonic coefficients of the displacements in the medio-lateral (ML), antero-posterior (AP), and vertical (V) directions were calculated via discrete Fourier transform, and relevant accelerations were computed by analytical double differentiation. The root mean square of the accelerations were used to define three coefficients for quantifying the attenuations of the accelerations from pelvis to head, from pelvis to shoulder, and from shoulder to head.ResultsThe coefficients of attenuation were shown to be independent from the walking speed, and hence suitable for group and subject comparison.The acceleration in the AP direction was attenuated by the two groups both from pelvis to shoulder and from shoulder to head. The reduction of the shoulder to head acceleration, however, was less effective in older women, suggesting that the ability to exploit the cervical hinge to attenuate the AP acceleration is challenged in this population. Young women managed to exploit a pelvis to shoulder attenuation strategy also in the ML direction, whereas in the elderly group the head acceleration was even larger than the pelvis acceleration.ConclusionThe control of the head acceleration is fundamental when implementing a locomotor strategy and its loss could be one of the causes for walking instability in elderly women.

Who May Have Durable Benefit From Robotic Gait Training? A 2-Year Follow-Up Randomized Controlled Trial in Patients With Subacute Stroke

Background and Purpose— Robotic-assisted walking training after stroke aims to enhance the odd of regaining independent gait. Recent studies have suggested that this approach is more effective than conventional therapy alone only in severely affected patients. We determined whether these results persist at long-term follow-up. Methods— Forty-eight nonambulant participants after subacute stroke were stratified by motricity index into high (<29) and low (≥29) motor impairment groups. Each arm was randomized to a robotic or control group at a mean of 20 days after stroke. All patients underwent 2 therapy sessions per day, 5 days per week, for 3 months. Robotic group subjects underwent 20 sessions of robotic-assisted gait training in the first 4 weeks of inpatient therapy and abbreviated conventional therapy, whereas control group patients received only conventional gait training. The primary outcome was Functional Ambulation Category, and secondary measures were the Rivermead Mobility Index and Barthel Index scores. The scales were administered before and after the inpatient stay and 2 years after discharge. Results— At follow-up, as at discharge, the low motricity robotic group improved more than the control group counterpart with regard to functional ambulation category (4.7±0.5 versus 3.1±1.5, P=0.002), Barthel Index (76.9±11.5 versus 64.7±14.0, P=0.024), and Rivermead Mobility Index (11.8±3.5 versus 7.0±3.6, P=0.010), whereas conventional and robotic therapies were equally effective in the high motricity groups. Conclusions— The higher efficacy of the combination of robotic therapy and conventional therapy versus conventional therapy alone that was observed at discharge only in patients with greater motor impairments was sustained after 2 years.

Seven Capital Devices for the Future of Stroke Rehabilitation

Stroke is the leading cause of long-term disability for adults in industrialized societies. Rehabilitations efforts are tended to avoid long-term impairments, but, actually, the rehabilitative outcomes are still poor. Novel tools based on new technologies have been developed to improve the motor recovery. In this paper, we have taken into account seven promising technologies that can improve rehabilitation of patients with stroke in the early future: (1) robotic devices for lower and upper limb recovery, (2) brain computer interfaces, (3) noninvasive brain stimulators, (4) neuroprostheses, (5) wearable devices for quantitative human movement analysis, (6) virtual reality, and (7) tablet-pc used for neurorehabilitation.

The Efficacy of Balance Training with Video Game-Based Therapy in Subacute Stroke Patients: A Randomized Controlled Trial

The video game-based therapy emerged as a potential valid tool in improving balance in several neurological conditions with controversial results, whereas little information is available regarding the use of this therapy in subacute stroke patients. The aim of this study was to investigate the efficacy of balance training using video game-based intervention on functional balance and disability in individuals with hemiparesis due to stroke in subacute phase. Fifty adult stroke patients participated to the study: 25 subjects were randomly assigned to balance training with Wii Fit, and the other 25 subjects were assigned to usual balance therapy. Both groups were also treated with conventional physical therapy (40 min 2 times/day). The main outcome was functional balance (Berg Balance Scale-BBS), and secondary outcomes were disability (Barthel Index-BI), walking ability (Functional Ambulation Category), and walking speed (10-meters walking test). Wii Fit training was more effective than usual balance therapy in improving balance (BBS: 53 versus 48, P = 0.004) and independency in activity of daily living (BI: 98 versus 93, P = 0.021). A balance training performed with a Wii Fit as an add on to the conventional therapy was found to be more effective than conventional therapy alone in improving balance and reducing disability in patients with subacute stroke.

Assessment of upper-body dynamic stability during walking in patients with subacute stroke.

The analysis of upper-body acceleration is a promising and simple technique to quantitatively assess dynamic gait stability. However, this method has rarely been used for people with stroke, probably because of some technical issues still not addressed. We evaluated the root-mean-square (RMS) and harmonic ratio of trunk accelerations for a group of 15 inpatients with subacute stroke who were able to walk (61.4 +/- 14.9 yr) and compared them with those of an age-matched group of nondisabled subjects (65.1 +/- 8.8 yr) and those of a highly functional group of young nondisabled subjects (29.0 +/- 5.0 yr). Small (<2%) but significant (p < 0.03) differences were found in RMS values obtained by applying the two most common computational approaches: (1) averaging among individual-stride RMS values and (2) computing the RMS value over the entire walking trial without stride partitioning. We found that the intersubject dependency of acceleration RMS values by selected walking speed was specific for each group and for each of the three body axes. The analysis of ratios between these three accelerations provided informative outcomes correlated with clinical scores and not affected by walking speed. Our findings are an important step toward transferring accelerometry from human movement analysis laboratories to clinical settings.

Development and decline of upright gait stability.

Upright gait is a peculiar characteristic of humans that requires the ability to manage upper body dynamic balance while walking, despite the perturbations that are generated by movements of the lower limbs. Most of the studies on upright gait stability have compared young adults and the elderly to determine the effects of aging. In other studies, the comparison was between healthy subjects and patients to examine specific pathologies. Fewer researches have also investigated the development of upright gait stability in children. This review discusses these studies in order to provide an overview of this relevant aspect of human locomotion. A clear trend from development to decline of upright gait stability has been depicted across the entire lifespan, from toddlers at first steps to elderly. In old individuals, even if healthy, the deterioration of skeletal muscle, combined with sensorial and cognitive performance, reduces the ability to maintain an upright trunk during walking, increasing the instability and the risk of falls. Further, the pathological causes of altered development or of a sudden loss of gait stability, as well as the environmental influence are investigated. The last part of this review is focused on the control of upper body accelerations during walking, a particularly interesting topic for the recent development of low-cost wearable accelerometers.

Stability and Harmony of Gait in Children with Cerebral Palsy.

The aim of this study was to quantitatively assess the stability and harmony of gait in children with cerebral palsy. Seventeen children with spastic hemiplegia due to cerebral palsy (5.0±2.3 years old) who were able to walk autonomously and seventeen age-matched children with typical development (5.7±2.5 years old, p=0.391) performed a 10-m walking test with a wearable device fixed to their lower trunk and included a triaxial accelerometer and three gyroscopes. Three parameters related to gait stability and three related to gait harmony were computed; all of these yielded significant differences between children with cerebral palsy and those with typical development (p<0.020 for all the computed parameters). In the latter group of children, trunk accelerations were found to be negatively correlated with age (partial correlation controlled for walking speed: R(p)<-0.58, p>0.020). Conversely, in children with cerebral palsy, the upper body accelerations were proportionally correlated with their gait speed (R=0.548, p=0.023 in the antero-posterior direction) but not with their age (p>0.05). This finding can be related both to difficulties in managing the higher upper body accelerations involved in rapid walking and to compensation strategies.

Reduced-Intensity Modified Constraint-Induced Movement Therapy Versus Conventional Therapy for Upper Extremity Rehabilitation After Stroke A Multicenter Trial

Background. Constraint-induced movement therapy (CIMT) is a rehabilitation approach for arm paresis consisting of an intensive schedule of treatment (6 h/d). The high demand of resources for CIMT is a critical issue for its implementation in the Italian health system. Objective. To compare the effects of a reduced-intensity modified CIMT (mCIMT) program that included splinting the unaffected arm for 12 hours daily with the effects of a conventional rehabilitation program for arm paresis in patients with stroke. Methods. Sixty-six participants with hemiparesis (3-24 months poststroke) who could extend the wrist and several fingers at least 10° were randomly assigned to mCIMT or conventional rehabilitation. Each group underwent 10 (2 h/d) treatment sessions (5 d/wk for 2 weeks). Patients were assessed with the Wolf Motor Function Test (WMFT-FA and WMFT-T), the Motor Activity Log (MAL-AOU and MAL-QOM), and the Ashworth Scale before and after treatment and 3 months later. Results. Between-groups analysis showed that the mCIMT group overall had greater improvement than the control group in terms of the WMFT-FA (P = .010), MAL-AOU (P < .001), and MAL-QOM (P < .001). Differences between groups were significant both after treatment (P < .01) and at the 3-month follow-up (P < .01), although 40% of participants did not complete the 3-month assessment. Furthermore, the mCIMT group showed a greater decrease of Ashworth Scale score than the control group at 3 months (P = .021). Conclusion. Two hours of CIMT may be more effective than conventional rehabilitation in improving motor function and use of the paretic arm in patients with chronic stroke.