Powered robotic exoskeletons in post-stroke rehabilitation of gait: a scoping review
Louie and Eng Journal of NeuroEngineering and Rehabilitation
Powered robotic exoskeletons in post- stroke rehabilitation of gait: a scoping review
Dennis R. Louie 0 2
Janice J. Eng 0 1
0 Rehabilitation Research Program, Vancouver Coastal Health Research Institute , Vancouver, BC , Canada
1 Department of Physical Therapy, University of British Columbia , 212-2177 Wesbrook Mall, Vancouver, BC V6T 1Z3 , Canada
2 Graduate Program in Rehabilitation Sciences, University of British Columbia , Vancouver, BC , Canada
Powered robotic exoskeletons are a potential intervention for gait rehabilitation in stroke to enable repetitive walking practice to maximize neural recovery. As this is a relatively new technology for stroke, a scoping review can help guide current research and propose recommendations for advancing the research development. The aim of this scoping review was to map the current literature surrounding the use of robotic exoskeletons for gait rehabilitation in adults post-stroke. Five databases (Pubmed, OVID MEDLINE, CINAHL, Embase, Cochrane Central Register of Clinical Trials) were searched for articles from inception to October 2015. Reference lists of included articles were reviewed to identify additional studies. Articles were included if they utilized a robotic exoskeleton as a gait training intervention for adult stroke survivors and reported walking outcome measures. Of 441 records identified, 11 studies, all published within the last five years, involving 216 participants met the inclusion criteria. The study designs ranged from pre-post clinical studies (n = 7) to controlled trials (n = 4); five of the studies utilized a robotic exoskeleton device unilaterally, while six used a bilateral design. Participants ranged from sub-acute (<7 weeks) to chronic (>6 months) stroke. Training periods ranged from single-session to 8-week interventions. Main walking outcome measures were gait speed, Timed Up and Go, 6-min Walk Test, and the Functional Ambulation Category. Meaningful improvement with exoskeleton-based gait training was more apparent in sub-acute stroke compared to chronic stroke. Two of the four controlled trials showed no greater improvement in any walking outcomes compared to a control group in chronic stroke. In conclusion, clinical trials demonstrate that powered robotic exoskeletons can be used safely as a gait training intervention for stroke. Preliminary findings suggest that exoskeletal gait training is equivalent to traditional therapy for chronic stroke patients, while sub-acute patients may experience added benefit from exoskeletal gait training. Efforts should be invested in designing rigorous, appropriately powered controlled trials before powered exoskeletons can be translated into a clinical tool for gait rehabilitation post-stroke.
Stroke; Cerebrovascular accident; Robotic exoskeleton; Gait rehabilitation; Scoping review
Stroke is a leading cause of acquired disability in the
world, with increasing survival rates as medical care and
treatment techniques improve [
]. This equates to an
increasing population with stroke-related disability [
who experience limitations in communication, activities
of daily living, and mobility . A majority of this
population ranks recovering the ability to walk or
improving walking ability among their top rehabilitation
]; furthermore, the ability to walk is a
determining factor as to whether an individual is able to
return home after their stroke . However, 30 – 40 % of
stroke survivors have limited or no walking ability even
after rehabilitation [
] and so there is an ongoing need
to advance the efficacy of gait rehabilitation for stroke
Powered robotic exoskeletons are a recently developed
technology that allows individuals with lower extremity
weakness to walk [
]. These wearable robots strap to the
legs and have electrically actuated motors that control
joint motion to automate overground walking. Powered
exoskeletons were originally designed to be used as an
assistive device to allow individuals with complete spinal
cord injury to walk [
]. However, because they allow
for walking without overhead body weight support or a
treadmill, they have gained attention as an alternate
intervention for gait rehabilitation in other populations
such as stroke where repetitive gait training has been
shown to yield improvements in walking function [
]. Several powered exoskeletons are already
commercially available, such as the Ekso (Ekso Bionics, USA),
Rewalk (Rewalk Robotics, Israel), and Indego (Parker
Hannifin, USA) exoskeletons, with more being
There have been many forms of gait retraining
proposed for stroke survivors. Conventional physical
therapy gait rehabilitation leads to improvements in speed
and endurance [
], particularly when conducted early
]. However, conventional gait retraining
using hands-on assistance can be taxing on therapists;
the number of steps actually taken in a session reflects
this and has been shown to be low in sub-acute hospital
]. Many of the proposed
technologybased gait intervention strategies have focused on
reducing the physical strain to therapists while increasing the
amount of walking repetition that individuals undergo.
For example, body weight-supported treadmill training
(BWSTT) allows therapists to manually move the
hemiparetic limb in a cyclical motion while the patient’s
trunk and weight are partially supported by an overhead
harness system; this has shown improvements in stroke
survivors’ gait speed and endurance compared to
conventional gait training [
], yet still places a high
physical demand on therapists. Advances in technology have
led to treadmill-based robotics, such as the Lokomat
(Hocoma, Switzerland), LOPES (University of Twente,
Netherlands), and G-EO (Reha-Technology,
Switzerland), which have bracing that attaches to the
patient’s legs to take them through a walking motion on
the treadmill. The appeal of this technology is that it can
provide substantially higher repetitions for walking
practice than BWSTT without placing strain on therapists;
however, there is conflicting evidence regarding the
efficacy of treadmill-based robotics for gait training
compared to conventional therapy or BWSTT. Some studies
have shown that treadmill robotics improve walking
independence in stroke [
] but do not improve speed
or endurance [
]. There has been some sentiment
that such technology has not lived up to the
expectations originally predicted based on theory and practice
]. One argument is that these treadmill robotics with
a pre-set belt speed, combined with body weight
support, create an environment where the patient has less
control over the initiation of each step [
argument against treadmill-based gait training is the lack
of variability in visuospatial flow, which is an essential
challenge of overground walking [
]. Powered robotic
exoskeletons, though similar in structure to
treadmillbased robotics, differ in that they require active
participation from the user for both swing initiation and foot
placement; for example, some exoskeletons have control
strategies which will only assist the stepping motion
when it detects adequate lateral weight-shifting [
Furthermore, because the powered exoskeletons are used
for overground walking, it requires the user to be
responsible for maintaining trunk and balance control, as
well as navigating their path over varying surfaces.
While these powered exoskeletons hold promise, the
literature surrounding their use for gait training is only
just beginning to gather, with the majority focusing on
spinal cord injury [
]. Several [
reviews have shown safe usage, positive effects as an
assistive device, and exercise benefits for individuals with
spinal cord injury. Only one systematic review [
specifically focusing on powered exoskeletons has included
studies involving stroke participants, though studies in
spinal cord injury and other conditions were also
included. This review focused exclusively on the Hybrid
Assistive Limb (HAL) exoskeleton (Cyberdyne, Japan),
(which currently is not approved for clinical use outside
of Japan), and found beneficial effects on gait function
and walking independence; however, the results were
combined generally across all included patient
populations and not specifically for stroke.
Given that this is a relatively new intervention for
stroke, the objective of this scoping review was to map
the current literature surrounding the use of powered
robotic exoskeletons for gait rehabilitation in post-stroke
individuals and to identify gaps in the research. The
second objective of this scoping review was to preliminarily
explore the efficacy of exoskeleton-based gait
rehabilitation in stroke. As this is a relatively new technology for
stroke, a scoping review can help guide current research
and propose recommendations for advancing the
This scoping review was conducted in accordance with
the framework proposed by Arksey and O’Malley [
and guided by the refined process highlighted by Levac
et al. [
OVID MEDLINE, Embase, Cochrane Central Register
of Controlled Trials, PubMed, and CINAHL databases
were accessed and searched from inception on October
14, 2015. We combined the search terms (robot* OR
exoskeleton OR “powered gait orthosis” OR PGO OR
HAL OR “hybrid assistive limb” OR ReWalk OR Ekso
OR Indego) AND (stroke OR CVA OR “cerebrovascular
accident” OR “cerebral infarct” OR “cerebral
hemorrhage” OR hemiplegia OR hemiparesis OR ABI
OR “acquired brain injury”) AND (gait OR walk OR
walking OR ambulation), with humans and English
language as limits.
Inclusion criteria were full-text, peer-reviewed articles
that used a powered robotic exoskeleton with adults
post-stroke as an intervention for gait rehabilitation.
Articles were included if they reported functional walking
outcomes (e.g., speed, distance, independence). We
defined a powered robotic exoskeleton as a wearable
robotic device which actuates movement of at least one
joint while walking, either unilaterally or bilaterally. We
further defined powered robotic exoskeletons as
standalone devices that can be used for overground walking,
with programmable control. Articles were excluded if
they: reported only technology development; reported
only electromyography, physiological cost, or joint
kinematic data; combined other interventions (e.g.,
functional electrical stimulation); included healthy
participants or children; utilized a treadmill-based device
(i.e., the exoskeleton and treadmill are a single device,
where the exoskeleton cannot be used separately
overground); included mixed diagnosis participants (<50 %
stroke); or if only an abstract was available.
Titles and abstracts were screened for relevance by
two reviewers (DRL, CC) according to the inclusion and
exclusion criteria above. In the event of conflict, a third
reviewer (JJE) was consulted for resolution. Full-texts
were then screened and reference lists of all selected
articles were searched for additional studies. Included
articles were then examined to extract data regarding study
design, exoskeleton device, participant characteristics,
intervention, training period, outcome measures, adverse
effects, and results. We examined the changes in
functional walking outcomes relative to clinically meaningful
change values published in the literature (Table 1).
As seen in Fig. 1, our electronic database search
returned 440 unique titles. Only one additional article
was identified through reference list searching. After
screening titles, abstracts, and full-texts for eligibility, 11
articles were included [
]. All 11 articles were
published in the last five years, with seven [
] published in the last two years. Five studies were
conducted in the United States, five in Japan, and one in
Of the included studies, three were randomized
controlled trials (RCTs) [
31, 35, 36
], and one was a
nonrandomized controlled study [
]. The rest were a
variety of single-group pre-post clinical trials as seen in
Table 2. Of the three RCTs, two were smaller in size (n
= 24 and n = 22) and considered pilot studies [
Across the 11 studies, there was a total of 216
(male/female:136/80) participants with stroke
enrolled (Table 2), with variability in the inclusion
criteria for participation. Seven studies [
included participants with chronic stroke (at least six
months post-stroke). Four studies [
investigated the exoskeleton with sub-acute participants
(less than six months post-stroke) during inpatient
rehabilitation. The majority of participants were in
the 50 – 70 age range. Six studies [
specifically enrolled participants with the ability to
walk without physical assistance from a therapist,
permitting walking devices such as a cane or walker,
while three studies [
31, 32, 34
] specified a
requirement of needing manual physical assistance to walk.
The former studies aimed to improve mobility for
ambulatory individuals with chronic stroke, whereas
the latter sought to restore independent ambulation
for sub-acute stroke participants. The other two
] enrolled participants with a mix of
The included studies investigated a variety of
exoskeletons, each having different set-ups and control
mechanisms. Five studies [
31, 36, 37, 40, 41
] used a robotic
exoskeleton unilaterally on the affected leg, while
another five studies [
32, 34, 35, 38, 39
] used a bilateral
set6MWT six-minute walk test, 10MWT ten meter walk test, FAC functional ambulation category, MCID minimal clinically important difference, MDC minimal
detectable change, TUG timed up and go
up for gait training. One study [
participants, as they were able, from a bilateral design to a
unilateral configuration. The most studied exoskeleton was
the HAL, used in six studies [
31–34, 37, 38
]; in these
studies, participants’ hip and knee joints were electrically
actuated in a walking motion. In one study  the H2
exoskeleton (Technaid SL, Spain), assisted the hip, knee,
and ankle joints. Four studies [
35, 36, 40, 41
] utilized an
exoskeleton powering only one joint of the lower
extremity (either hip or knee, uni- or bilaterally); no
studies were found in which only the ankle was actuated
during gait. Control of the exoskeletons ranged from
remote-control button activation  to active
movement control of stepping; the devices are able to detect
movement intention through monitoring joint angles
and limb torque [
35, 36, 40, 41
], or through bio-electric
signalling of muscle activity [
31–34, 37, 38
exoskeletons except the HAL provided supplementary gait
assistance on an as-needed basis, in which the user
generates as much of the walking movements as possible
and the device provides extra torque or support to
ensure step completion. The HAL has two modes, one that
provides complete stepping assistance and one that
adapts to user force generation. Table 3 further details
the exoskeletons, their control strategies, and the level
of assistance provided.
There was variability in the training period of the
included studies, ranging from a single session [
several weeks [
31–33, 39, 40
] or months [
training. Training duration lasted from 20 – 90 min per
session, and frequency ranged from two to five sessions
per week. Table 2 details the different training periods
for each study.
The training protocol employed in each study differed,
and varied depending on the study design, length of the
training period, and exoskeleton used (Table 2).
Generally, subjects were progressed as tolerated from
weightbearing functional tasks (sit-to-stand, standing balance,
weight shifting) to walking practice while wearing the
exoskeleton device. Two studies [
] had participants
train on a treadmill, which allowed therapists to adjust
the walking speed externally. The most detailed training
protocols were described in the controlled trials [
], wherein individuals were progressed according to
various intensity guidelines such as rate of perceived
exertion (RPE) [
] and non-exoskeletal walking speed
]. For example, Yoshimoto et al. [
] advanced the
training speed to 1.5-1.7 times the maximal
nonexoskeletal 10MWT walking speed before each session.
1 – 2 person assist
ambulation (HAL group
n = 11, mean 58.9 days
n = 11, mean 50.6 days
Nilsson et al. Sub-acute stroke
] 1 – 2 person assist
study (n = 8, 6 – 46 days
HAL group – gait training while wearing 1) TUG – No significant difference in
HAL, facilitating improvements in walking improvement between groups
ability, partial BWS if needed; progress as 2) 6MWT – No significant difference in
able from complete assistance by device to improvement between groups
assist-as-needed through bioelectric signal 3) Gait speed – No significant difference in
detection improvement between groups
Conventional group – facilitate 4) FAC – HAL group improved significantly
improvements in walking ability, (p = 0.04) more than Conventional group
customized to functional level; speed and (change of +1.1 for HAL group; change of
duration of walking gradually increased +0.6 for Conventional group)
Progression from weight shift control to
bioelectric signalling control, training with
BWS on treadmill; progression of speed
and BWS as tolerated
Walking on treadmill in exoskeleton,
progress from complete control to
Walking and stair practice after standing
practice in exoskeleton
1) 10MWT – median change of +0.24 m/s,
4 previously non-ambulatory progressed to
2) FAC – median change of +1.5 (from 0 to
1) 10MWT – change of +0.1 m/s for
Brunnstrom stage III (greater severity with
lower stage) (n = 12); no change for
Brunnstrom stage IV (n = 7); change of
+0.1 m/s for Brunnstrom stage V (n = 12);
change of +0.4 m/s for Brunnstrom stage
VI (N = 10)
1) 10MWT – positive change for 14 of 16
patients (values not provided)
1) Gait speed – No significant difference in
improvement between groups
SMA group – 30 minutes of high intensity
overground walking with SMA (12-16 RPE
or 75 % HR max) and 15 minutes of
dynamic functional gait training with SMA
(varied surfaces, multi-directional stepping,
stair climbing, obstacles, community
Functional task specific training group –
15 minutes of high intensity overground
walking training and 30 minutes of
functional goal-based mobility training
AlterG group – standardized overground 1) TUG – No significant difference between
functional tasks including transfers, groups
stepping, turning, reaching, gait training, 2) 6MWT – No significant difference in
stairs and curbs while wearing exoskeleton improvements between groups
Exercise group – group exercises including 3) 10MWT – No significant difference in
relaxation, meditation, self-stretching, active improvement between groups
range of motion of upper and lower limbs,
minimal gait training (5 min/session)
HAL group – 20 minutes of HAL walking 1) TUG – HAL group improved significantly
per session, with some BWS, walking at compared to Conventional PT group
speed 1.5-1.7 times max walking speed (change of -11.5 s for HAL group; change
without device of +0.1 s for Conventional PT group)
Conventional PT group – exercise to 2) 10MWT – HAL group improved
improve walking ability including static and significantly compared to Conventional PT
dynamic postural tasks, range of motion, group (change of +0.21 m/s for HAL
and 20 minutes of overground walking group; change of -0.02 m/s for
training Conventional PT group)
6MWT six-minute walk test, 10MWT ten meter walk test, BWS body weight support, FAC functional ambulation category, H2 H2 exoskeleton, HAL hybrid assistive
limb, HR heart rate, SMA stride management assist system, PT physical therapy, RCT randomized controlled trial, RPE rate of perceived exertion, TUG timed up
Bold indicates value surpasses established meaningful change score detailed in Table 1
Several studies [
31, 32, 37, 38
] allowed some body
weight support using an overhead harness to improve
Ten of the 11 studies included a measure of gait
speed in their assessment of walking ability, either
measuring it directly or via the 10-m Walk Test
(10MWT). Five studies [
31, 36, 39–41
walking endurance by means of a 6-min Walk Test
(6MWT), and seven studies [
] assessed the
Timed Up and Go (TUG) test, which is a measure of
functional mobility as it includes sit-to-stand and
turning. Two studies [
] also included level of
independence or assistance in their assessment of
walking ability, using the Functional Ambulation
Category (FAC). Participants were not wearing an
exoskeleton device when assessed for the above measures
in all studies, but gait aids such as canes and walkers
Initiated by hand buttons on walker
Initiated by movement
Internal sensors detect hip joint angle to regulate walking
Initiated by movement (2 modes)
Internal sensors detect lateral weight shift
Surface electrodes detect muscle activation via bioelectric signals
Initiated by movement
Internal sensors detect movement intention via variable force
Assist-as-needed for swing
Assist-as-needed for swing
Full-assistance for swing
Assist-as-needed for swing
Assist-as-needed for stance, free
AlterG AlterG Bionic Leg, formerly Tibion Bionic Leg; H2 H2 exoskeleton; HAL Hybrid Assistive Limb; SMA Stride Management Assist system (Honda R&D
Effectiveness of exoskeleton-based gait training
Ten studies reported varying degrees of improved
walking ability after exoskeleton training (Table 2). Of the
four sub-acute stroke studies, only one [
] was a
randomized controlled trial (n = 22) which showed that
participants using the HAL experienced a significant
improvement in FAC scores compared to conventional
gait rehabilitation matched for training time, no longer
requiring manual assistance to walk after the training
period (medium effect size). However, they found no
significant difference between the HAL intervention and
conventional therapy for walking speed or endurance.
One small pre-post sub-acute study [
] (n = 8) also
found an improvement in the median FAC score of their
sub-acute participants from 0 (2-person assist to walk)
to 1.5 (1-person assist to walk) after exoskeleton-based
gait training. Participants in the two other pre-post
] in sub-acute stroke demonstrated
improvements in walking speed with only a few sessions, though
not all of their participants demonstrated a change
greater than the established minimal clinically important
difference (MCID) (Table 1).
Across the seven chronic stroke studies, improvements
in walking ability were less apparent. In an RCT with 50
], there was no significant difference
between the clinically meaningful improvements in gait
speed made by participants in either the exoskeleton or
functional training group matched for training time.
Similarly, participants using the AlterG Bionic Leg
(AlterG, USA) did not demonstrate significant
improvements compared to the control group or to baseline
after 18 training sessions in a small RCT with 24
]. In contrast, a nonrandomized controlled trial
] found significant and clinically meaningful
improvements in gait speed and TUG time after training using a
HAL compared to conventional physical therapy;
however, the control group did not receive the same number
of exercise sessions. One larger pre-post study [
] (n =
16) did not find changes in gait speed that were beyond
the established MCID (Table 1) while three small
prepost studies [
], each with three participants, found
varying results. Clinical improvements in endurance
were made by four participants in two of the pre-post
], using a minimal clinically important
difference of 34.4 m in the 6MWT.  Three participants
across the three smaller pre-post studies [
meaningful improvements in TUG scores. Four
participants in two of the pre-post studies [
demonstrated a clinically meaningful improvement in walking
speed, using an MCID of 0.06-0.14 m/s .
Eight studies confirmed that no adverse events occurred
during the course of the gait training intervention. One
] reported minor and temporary adverse effects
such as skin irritation and pain from cuffs and
bioelectric detection electrodes. Two studies [
] did not
report on adverse events. No studies reported adverse
effects on the therapists.
This scoping review was conducted to map the literature
surrounding the use of powered robotic exoskeletons for
gait retraining for individuals after stroke and to identify
preliminary findings and areas where further research is
required. This is a relatively new application of powered
exoskeletons, as they have only recently become
available for clinical use. As expected, there are only a small
number of studies published relevant to this topic.
There were four different powered exoskeletons
utilized amongst the included studies, ranging from
unilateral, single joint devices to bilateral, multi-joint robotics
with the capacity to detect volitional bioelectrical signals
to initiate powered movement. Other exoskeletons exist
on the commercial market for clinical application that
have not yet been investigated for stroke such as the
Ekso, Rewalk, and Indego (Parker Hannifin Corporation,
USA). Research with these other exoskeletons is
required to determine their clinical usefulness and would
also strengthen the literature in general support of
exoskeleton use for gait rehabilitation in stroke patients.
Studies comparing unilateral to bilateral designs may
also be another avenue for investigating the efficacy of
exoskeletal gait retraining.
The majority of the included studies investigated
exoskeleton-based gait training in chronic stroke
participants. However, the greatest amount of functional and
neurological recovery after stroke occurs in the first six
weeks after stroke [
]. In reflection of this, all four studies
in the sub-acute phase of stroke reported positive effects of
exoskeleton training. Two studies [
improved walking independence with repeated exoskeletal
gait training for more limited stroke participants, which is
in line with findings using treadmill-based robotics [
another study [
], there was significant improvement in
walking speed (0.4 m/s) for stroke participants who had
some voluntary motor control, but much less change
(0.1 m/s) for those without voluntary control. The
magnitude and parameter (ability, speed) of walking improvement
may vary depending on the initial functional presentation
of the exoskeleton user; furthermore, the spontaneous
recovery following stroke is a confounding factor for the
improvements reported that has yet to be rigorously
controlled for in the current literature.
Study findings were not consistent for chronic stroke
participants. All chronic stroke participants included
were ambulatory, and so studies investigated changes in
gait parameters rather than functional ability. While
there were modest, but not consistent changes in the
prepost studies, the more rigorous RCTs [
] did not show
a difference from their respective control groups when
groups were matched for exercise time and interaction with
a physical therapist. Even in studies with longer training
35, 36, 38, 41
], there was not a trend for greater
improvements. Despite receiving the repetitious practice
that is required for motor learning [
], chronic stroke
participants do not respond as positively to exoskeletal gait
training as sub-acute patients. This is consistent with
findings in a systematic review  of treadmill-based
exoskeleton devices for gait training in chronic, ambulatory
individuals with stroke. A possible explanation for this is
that once an individual is able to walk, they benefit more
from unconstrained walking practice with greater variability
and unpredictable challenges [
]. While powered
exoskeletons do not require the participant to use a treadmill, they
still constrain the user to a stereotyped movement pattern
and may thus under-challenge them.
The majority of included studies had small sample sizes,
which may have limited the power of their study findings
and analysis. In addition to this, the majority of these
studies were pilot feasibility or pre-post clinical studies;
recruitment and lack of a control group may have introduced bias
to their findings. For example, one study [
] used a
nonrandomized controlled design, where the control group was
formed of participants who were less able to attend the
study training protocol. These results inform the
preliminary evidence in the field and more rigorous, appropriately
powered randomized controlled trials will continue to
advance the clinical application of powered exoskeletons.
Future directions for research and suggestions for clinical practice
From our data synthesis we have identified various
considerations when using an exoskeleton for gait retraining
and propose several questions for future research:
1. Do non-ambulatory chronic stroke participants
experience the same improvement in walking ability as
sub-acute stroke participants when using an
exoskeleton device for gait retraining?
2. How does initial functional presentation impact the
nature of improvement in walking ability when using
an exoskeleton device for gait rehabilitation?
3. What is the impact of different exoskeletons
(number of joints actuated, level of assistance and
control of stepping) on gait rehabilitation in stroke?
4. What is the impact of using a bilateral design
compared to a unilateral design for gait
rehabilitation in hemiparetic stroke?
5. What is the optimal dose of exoskeletal gait training
for stroke patients to regain the most walking
6. How does overground exoskeletal gait training
compare to body weight-supported treadmill
7. Can exoskeletons be used to safely ambulate
2person assist patients early after stroke with minimal
injury risk to therapists?
Additionally, larger sample sizes and rigorous
methodology investigating the efficacy of powered exoskeletons
in stroke will further strengthen findings for or against
their utilization for gait rehabilitation.
At the moment there is insufficient evidence to advocate
in favour or against use of powered exoskeletons in
clinical practice. The patient’s acuity and functional
presentation need to be considered and the extent of benefit has
yet remain to be determined through high quality
research. The devices, however, have been shown to be safe
and feasible for use with stroke patients. They can be used
to mobilize more impaired individuals without physically
straining therapists. It thus remains up to therapists to use
their own clinical judgement of whether to utilize powered
exoskeletons with their patients for gait rehabilitation,
considering its application for weight-bearing, standing,
and automated walking.
There are a few limitations with the present review. This
review excluded non-English studies, which may have led to
an incomplete synthesis of data, given that some
exoskeletons are developed in non-English countries such as Japan,
Germany, Iran, Israel, and Spain. There was heterogeneity
in the studies, especially with variability in the training
protocols and exoskeletons utilized (control mechanism,
unilateral or bilateral application), which makes interpretation
of the results challenging. In addition, type, side, and
severity of stroke and comorbid conditions were not considered
in this review because of the scarcity of studies in this area.
As more research trials in stroke rehabilitation using
powered exoskeletons are conducted, a systematic review will
be able to address these additional considerations.
Currently, clinical trials demonstrate that powered
robotic exoskeletons can be used safely as a gait training
intervention for sub-acute and chronic stroke.
Preliminary findings suggest that exoskeletal gait training is
equivalent to traditional therapy for chronic stroke
patients, while sub-acute patients may experience added
benefit from exoskeletal gait training. Efforts should be
invested in designing rigorous, appropriately powered
controlled trials before it can be translated into a clinical
tool for gait rehabilitation post-stroke.
10MWT, 10-m walk test; 6MWT, 6-min walk test; BWSTT, body weight-supported
treadmill training; FAC, functional ambulation category; HAL, hybrid assistive
limb; MCID, minimal clinically important difference; RCT, randomized controlled
trial; RPE, rate of perceived exertion; TUG, timed up and go
The authors acknowledge and thank Christina Cassady (CC), who acted as
second reviewer in the search portion of this review.
The project was supported by funding from a Grant-in-Aid from the Heart
and Stroke Foundation of Canada and the Canada Research Chairs Program.
Availability of data and materials
No original data is presented in this review.
DRL formulated the idea, performed the search, and prepared the
manuscript for this review. JJE participated in the writing process. Both
authors read and approved the final manuscript.
The authors declare that they have no competing interests.
Consent for publication
Ethics approval and consent to participate
This scoping review did not collect original data on human subjects;
therefore ethics approval is not applicable. All studies included in this review
reported receiving ethical approval and gaining consent from their
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