Table 1: Summary of clinical researches of active training applied in platform-based ankle robots.

StudySubjects (n)Subject characteristicsSubject age (yr)GroupCourse of trainingRobotControl strategiesResearching achievement

Deutsch et al. [66]6Subjects with chronic strokeNot statedSingle group4 weeks
12 sessions
Rutgers AnkleVR game training
Haptic effects
Telerehabilitation
Therapeutic effects of injured ankles were not significantly different when therapists were in the same room with patients or appeared in front of patients remotely by a webcam.
Mirelman et al. [13]18Subjects with chronic hemiparesis41–75Robot VR group (9)
Robot group (9)
4 weeks
12 sessions
Rutgers AnkleVR game training
Easy to difficult
Haptic effects
Training integrated with VR games were a better selection for ankle rehabilitation therapies.
Burdea et al. [10]3Subjects with CP7–12Single group12 weeks
36 sessions
Rutgers Ankle CPVR game training
Easy to difficult
Haptic effects
Performance of playing game was mapped to the physical improvement evaluated clinically in ankle strength, gait kinematics, and speed.
Forrester et al. [52]8Subjects with chronic stroke43–75Single group6 weeks
18 sessions
AnklebotVR game training
Easy to difficult
Assist as needed
Robotic feedback training would be a valuable supplement to locomotor therapies.
Roy et al. [54]14Healthy subjects
Subjects with chronic stroke
49–64
53–74
Control group (7)
Stroke group (7)
1 sessionAnklebotVR game training
Easy to difficult
Assist as needed
Firstly observed that immediately following and 48 hours after a single session of anklebot training, motor control of paretic ankles were improved but not for nondisabled ankles.
Roy et al. [2]8The same subjects as those in [52]43–75Single group6 weeks
18 sessions
AnklebotVR game training
Easy to difficult
Assist as needed
Performance-based progression
Application of EMG
Anklebot training with progressive targets significantly decreased PAS of paretic ankles, even to the normal range in dorsiflexion direction. Furthermore, increased compliance of paretic ankles would result in improvement in unassisted overground walking.
Goodman et al. [23]10Subjects with chronic hemiparetic stroke42–82HR group(5)
LR group(5)
3 weeks
9 sessions
AnklebotVR game training
Easy to difficult
Assist as needed
Application of EEG
Rewards
Rewards integrated with performance of subjects conducting anklebot training could accelerate activity-dependent brain plasticity to improve motor control.
Forrester et al. [21]34Subjects with hemiparetic stroke57–66Robot group (18)
Stretching group (16)
10 sessionsAnklebotVR game training
Assist as needed
Manual stretching
Robot group achieved more improvement in walking speed, motor control, and gait patterning than stretching group.
Forrester et al. [55]26Subjects with chronic hemiparetic gait53–63SRT group (12)
TMR group (14)
6 weeks
18 sessions
Anklebot
Treadmill
VR game training
Easy to difficult
Assist as needed
Performance based progression
Anklebot therapy would be more effective if integrated with locomotor treadmill.
Michmizos et al. [63]3Subjects with CP or lesion of the common peroneal nerve9Single group in clinicAt least 3 weeks
9 sessions
PediAnklebotVR game training
Easy to difficult
Assist as needed
Subjects obtained significant improvement of explicit motor learning assessed with less jerky, better controlled, and increased speed of movements and implicit motor learning evaluated by the reduction of the average RT (reaction time).
Krebs et al. [60]4Subjects with CP7–11Single group6 weeks
12 sessions
PediAnklebotVR game training
Easy to difficult
Assist as needed
PediAnklebot could provide better therapeutic effect on ankle rehabilitation through harnessing plasticity among children with CP.
Wu et al. [59]12Subjects with spastic CP5–10Single group6 weeks
18 sessions
Portable rehabilitation robotI-passive stretching
VR game training
A-active movement
R-active movement
Active rehabilitation training combined with passive stretching was beneficial for children with CP.
Waldman et al. [53]23Subjects with poststroke43–60Robot group (11)
Control group (12)
6 weeks
18 sessions
Portable rehabilitation robotI-passive stretching
VR game training
A-active movement
R-active movement
Robotic rehabilitation training should be a beneficial supplement to rehabilitation programs.
Sukal-Moulton et al. [58]28Subjects with CP5–12Single group6 weeks
12 sessions
IntelliStretch rehabilitation robotPassive stretching
VR game training
A-active movement
R-active movement
Rehabilitation training combining active movement and passive stretching together was feasible in clinic application.
Chen et al. [65]23Subjects with CP5–17Single group6 weeks
18 sessions
Portable rehabilitation robot with TELEI-passive stretching
VR game training
A-active movement
Telerehabilitation
Robotic rehabilitation training with teleassistance was not only convenient and economical but also effective for patients.
Ren et al. [62]10Subjects with acute poststroke38–71Single group3 weeks
12 sessions
An in-bed wearable robotic deviceI-passive stretching
VR game training
A-active movement
R-active movement
The in-bed active movement training combined with passive stretching met clinic requirements and could improve motor ability of ankle joints.
Chen et al. [14]41Subjects with CP5–17Home-based group (23)
Lab-based group (18)
6 weeks
18 sessions
A portable rehabilitation robotI-passive stretching
VR game training
A-active movement
R-active movement
Ankle rehabilitation training simply with audiovisual communication available from research engineers was feasible to be conducted at home.
Lee et al. [61]6Subjects with multiple sclerosis44–66Single group6 weeks
18 sessions
IntelliStretch rehabilitation robotPassive stretching
VR game training
A-active movement
R-active movement
Ankle rehabilitation training could provide subjects with MS better therapeutic effect on sensorimotor functions of lower limbs.
Zhou et al. [67]5Subjects with chronic stroke56–77Single group6 weeks
18 sessions
PNF assisted PKU-RARSPNF stretching
Passive stretching
Application of EMG
Robot-assisted PNF stretching was an effective therapy method to rehabilitate ankles with contracture and spasticity.
Zhou et al. [68]7Subjects with poststroke41–79Single group3 months
36 sessions
PNF assisted PKU-RARSPNF stretching
Passive stretching
Application of EMG
Robot-assisted PNF stretching was significantly effective in alleviating spasticity of lower limb and improving its motor function.
Chang et al. [56]29Subjects with hemiparesis after stroke18–81LF group (9)
MF group (11)
HF group (9)
6 weeks
18 sessions
AnklebotVR game training
Assist as needed
Robot-assisted ankle training was more beneficial to moderate and mild gait speed impairments.

A-active moment = assisted active movement; R-active movement = resisted active movement; PNF = proprioceptive neuromuscular facilitation; I-passive stretching = intelligent passive stretching; VR = virtual reality; CP = cerebral palsy; EEG = electroencephalograph; EMG = electromyography; LF group = low-function group; MF group = moderate-function group; HF group = high-function group. They have another group of subjects who applied to verify the function of the technology or system.