A randomized controlled trial of motor imagery combined with structured progressive circuit class therapy on gait in stroke survivors

Effects of motor imagery training on gait performance in individuals after stroke: a systematic review and meta-analysis

PURPOSE

This review systematically explores and summarise the effects of motor imagery training (MIT) compared to conventional therapy on gait performance in individuals after stroke.

MATERIALS AND METHODS

Randomised controlled trials (RCTs) were systematically searched in five electronic databases (PubMed, EMBASE, PsycINFO, OVID Nursing and CINAHL) from inception to 30 December 2022. Studies investigating MITs, targeted at individuals after stroke were eligible. Data were extracted related to study and intervention characteristics.

RESULTS

Sixteen studies were included. Compared with 'routine methods of treatment or training', the meta-analyses showed that MIT was more effective in improving cadence immediately post intervention (SMD: 1.22, 95% CI: 0.59, 1.85, p = 0.0001, I2 = 25%) and at 1- or 2-months post intervention (SMD: 0.78, 95% CI: 0.35, 1.20, p = 0.0004, I2 = 46%). The results also showed that MIT improves the step length of the affected side and the unaffected side at 1- or 2-months post intervention. Separate meta-analyses were also conducted on different tests of walking endurance (assessed by the 6-Minute Walk Test) and functional mobility (assessed by the Timed-Up-and-Go test).

CONCLUSIONS

MIT effectively improved gait performance. The findings in individuals after stroke remain inconclusive due to significant heterogeneity in included studies.

How Posture and Previous Sensorimotor Experience Influence Muscle Activity during Gait Imagery in Young Healthy Individuals

This study explores how gait imagery (GI) influences lower-limb muscle activity with respect to posture and previous walking experience. We utilized surface electromyography (sEMG) in 36 healthy young individuals aged 24 (±1.1) years to identify muscle activity during a non-gait imagery task (non-GI), as well as GI tasks before (GI-1) and after the execution of walking (GI-2), with assessments performed in both sitting and standing postures. The sEMG was recorded on both lower limbs on the tibialis anterior (TA) and on the gastrocnemius medialis (GM) for all tested tasks. As a result, a significant muscle activity decrease was found in the right TA for GI-1 compared to GI-2 in both sitting (p = 0.008) and standing (p = 0.01) positions. In the left TA, the activity decreased in the sitting posture during non-GI (p = 0.004) and GI-1 (p = 0.009) in comparison to GI-2. No differences were found for GM. The subjective level of imagination difficulty improved for GI-2 in comparison to GI-1 in both postures (p < 0.001). Previous sensorimotor experience with real gait execution and sitting posture potentiate TA activity decrease during GI. These findings contribute to the understanding of neural mechanisms beyond GI.

Effects of Motor Imagery Training for Lower Limb Dysfunction in Patients With Stroke: A Systematic Review and Meta-analysis of Randomized Controlled Trials

OBJECTIVE

The aim of the study is to determine the effects of motor imagery training associated with conventional rehabilitation therapies on lower limb motor function recovery in poststroke patients.

DESIGN

Comprehensive literature searches were performed to identify studies published before June 5, 2022. RevMan 5.3 software was used for meta-analysis. The quality of the included studies was assessed using the Cochrane risk-of-bias tool and the modified Jadad scale. The certainty of the evidence was evaluated with the Grading of Recommendations, Assessment, Development and Evaluations system.

RESULT

Twenty-three trials and/or 1109 participants with motor imagery training ability were included in this review. Motor imagery training combined with conventional rehabilitation therapies versus conventional rehabilitation therapies demonstrated significant benefits in motor function, balance function, temporospatial gait variables (walking speed, stride length, and cadence) and activities of daily living. Subgroup analysis demonstrated that motor imagery training-conventional rehabilitation therapies had a better effect on improvement in motor function and activities of daily living in the acute phase and had a greater benefit on walking speed in the chronic phase. In addition, motor imagery training-conventional rehabilitation therapies resulted in greater improvements in stride length, cadence, walking ability, and balance function in the subacute phase.

CONCLUSIONS

Motor imagery training-conventional rehabilitation therapies have better effects on the recovery of lower limb motor function in poststroke patients than conventional rehabilitation therapies, which may be most beneficial for lower extremity motor function recovery in the first 7 days to 6 mos.

Task-Oriented and Imitation-Oriented Movements in Virtual Reality Exercise Performance and Design

OBJECTIVE

This study investigated the influence of game features and practice type on human kinematic and muscular performance in a virtual reality exercise (VRE). Participants demonstrated changes in shoulder flexion angle and muscle activation under different virtual scenarios.

BACKGROUND

Conventional VRE studies often compared the outcomes between an experimental group that underwent exercise in VR and a real-world exercise control group, whereas comparisons between VRE programs are lacking. Besides, the attributes of VREs received little attention.

METHOD

Thirteen able-bodied participants performed upper extremity exercise movements in immersive VR using a head-mounted display. Participants performed task-oriented and imitation-oriented movements with different game features. Shoulder muscle activity (the deltoid, supraspinatus, and infraspinatus) and shoulder motion were collected.

RESULTS

Practice type (task-oriented, imitation-oriented) significantly influenced the flexion angle of the shoulder complex (F(1,11) = 9.53, p = .01), and the muscle activity of the supraspinatus (F(1,9) = 12.61, p = .006) and the infraspinatus (F(1,9) = 12.71, p = .006). Game features did not have a statistically significant effect on shoulder flexion angle or shoulder muscles' activations.

CONCLUSIONS

Compared to imitation-oriented practice, task-oriented practice elicited more intensive shoulder movements and muscular efforts but also induced greater movement variations. Substantial differences across game features levels should be further investigated to have significant effects.

APPLICATIONS

This research may help guide the design of future VREs. For strength training or rehabilitation where intensive practice is required, task-oriented practice should be considered; for movement learning where movement consistency is required, imitation oriented practice should be adopted.

Effectiveness of Rehabilitation Exercise in Improving Physical Function of Stroke Patients: A Systematic Review

Rehabilitation is a crucial part of recovery for stroke survivors, and numerous studies have examined various exercises and treatments of stroke. In addition, it is very important for patients to choose the timing of rehabilitation and what kind of rehabilitation they will proceed with. The purpose of the current study is to examine research investigating the effects of rehabilitation exercise programs in recovery of physical function in patients with stroke, based on aspects of their physical function, physical strength, and daily activities, and systematically examine their effects. Therefore, through systematic review, we have investigated the effects of interventions in rehabilitation exercise programs for recovery of physical function in patients with stroke. We collected relevant publications through the databases MEDLINE/PubMed and Google scholar. Twenty-one articles were ultimately selected for the analysis. We classified the rehabilitation programs and identified the trends of treatment for stroke survivors. Our review indicated that task-oriented therapy is still dominant, but various types of combined rehabilitations have been attempted. In addition, it was identified that physical and active rehabilitation were required rather than unconditional rest, even at an early stage. Home-based treatment was used for rapid recovery and adaptation to daily life during the mid-term period.

Comparison of high-intensive and low-intensive electromechanical-assisted gait training by Exowalk® in patients over 3-month post-stroke

BACKGROUND

This study was conducted to assess the effect of electromechanical-assisted gait training intensity on walking ability in patients over 3-month post-stroke.

METHODS

Data from two randomized controlled trials (RCTs) were collected under the same study design of assessment and intervention, excluding intervention time per session. After matching the inclusion criteria of two RCTs, the experimental groups of each RCT were defined as low-intensive (LI) and high-intensive (HI) group according to the intervention time per session. Primary outcome was the difference of the change in Functional Ambulatory Categories (FAC) between LI and HI gait training. Secondary outcomes were the difference of changes in mobility, walking speed, walking capacity, leg-muscle strength, balance and daily activity evaluated with Rivermead Mobility Index (RMI), 10 m walk test (10MWT), 6-min walk test (6MWT), Motricity Index (MI), Berg Balance Scale (BBS) and Modified Barthel Index (MBI) respectively.

RESULTS

The FAC improved after gait training in both groups. The secondary outcomes also improved in both groups except RMI and MI in HI group. The change of all outcomes were not different between groups except RMI. The change of RMI in the LI group was greater than that in the HI group statistically, but it did not meet minimal clinically important difference.

CONCLUSIONS

The improvement of walking ability after LI or HI gait training was not different if providing the same total gait training time. By providing the electromechanical gait training intensively, we could shorten the gait training period to improve walking ability and customize the training program according to the patient training abilities.

TRIAL REGISTRATION

Name of the registry: Clinical Research Information Service.

TRIAL REGISTRATION NUMBER

No. KCT0002195(RCT1), No. KCT0002552(RCT2). Date of registration: 10/04/2016(RCT1), 10/05/2017(RCT2). URL of the trial registry record: https://cris.nih.go.kr/cris/search.

Effects of action observation and motor imagery of walking on the corticospinal and spinal motoneuron excitability and motor imagery ability in healthy participants

Action observation (AO) and motor imagery (MI) are used for the rehabilitation of patients who face difficulty walking. Rehabilitation involving AO, MI, and AO combined with MI (AO+MI) facilitates gait recovery after neurological disorders. However, the mechanism by which it positively affects gait function is unclear. We previously examined the neural mechanisms underlying AO and MI of walking, focusing on AO+MI and corticospinal and spinal motor neuron excitability, which play important roles in gait function. Herein, we investigated the effects of a short intervention using AO+MI of walking on the corticospinal and spinal motor neuron excitability and MI ability of participants. Twelve healthy individuals participated in this study, which consisted of a 20 min intervention. Before the experiment, we measured MI ability using the Vividness of Movement Imagery Questionnaire-2 (VMIQ-2). We used motor evoked potential and F-wave measurements to evaluate the corticospinal and spinal motor neuron excitability at rest, pre-intervention, 0 min, and 15 min post-intervention. We also measured corticospinal excitability during MI of walking and the participant’s ability to perform MI using a visual analog scale (VAS). There were no significant changes in corticospinal and spinal motor neuron excitability during and after the intervention using AO+MI (p>0.05). The intervention temporarily increased VAS scores, thus indicating clearer MI (p<0.05); however, it did not influence corticospinal excitability during MI of walking (p>0.05). Furthermore, there was no significant correlation between the VMIQ-2 and VAS scores and changes in corticospinal and spinal motor neuron excitability. Therefore, one short intervention using AO+MI increased MI ability in healthy individuals; however, it was insufficient to induce plastic changes at the cortical and spinal levels. Moreover, the effects of intervention using AO+MI were not associated with MI ability. Our findings provide information about intervention using AO+MI in healthy individuals and might be helpful in planning neurorehabilitation strategies.

Effects of Motor Imagery as a Complementary Resource on the Rehabilitation of Stroke Patients: A Meta-Analysis of Randomized Trials

BACKGROUND

Stroke is the second leading cause of death and a leading cause of disability worldwide. Motor imagery is a technique that can be utilized in the rehabilitation process to improve the lives of patients with a functional disability acquired by this pathology.

AIM

To evaluate the effects of motor imagery as a complementary intervention for the rehabilitation of stroke patients.

METHODS

We conducted a systematic review in MEDLINE/PubMed, Scopus, Web of Science, and PEDro databases. We included randomized controlled trials (RCTs) that used motor imagery as a complementary resource for the rehabilitation of patients affected by stroke, who had motor function and functional independence as outcomes.

RESULTS

Of the 1,473 studies found, ten RCTs were included. Regarding the interventions, motor imagery was associated with traditional rehabilitation, virtual reality, physical practice, structured progressive circuit class therapy, and electromyography. The upper and lower extremity performance were accessed through the Fugl-Meyer Assessment (FMA) and gait speed, respectively. Although the practice of motor imagery at least twice a week during three weeks showed to be effective in improving the motor performance of post-stroke patients, the studies' protocols present a high heterogeneity, with training session times lasting between 30 to 180 minutes and a post-stroke invention window of one to 12 months.

CONCLUSIONS

Motor imagery has been shown to be an efficacious technique in the treatment of post-stroke patients when used as a complement to traditional rehabilitation techniques. However, greater standardization of interventions and studies with higher methodological quality are required to determine further conclusions.

Cluster decomposing and multi-objective optimization based-ensemble learning framework for motor imagery-based brain-computer interfaces

OBJECTIVE

Motor imagery (MI) is a mental representation of motor behavior and a widely used pattern in electroencephalogram (EEG) based brain-computer interface (BCI) systems. EEG is known for its non-stationary, non-linear features and sensitivity to artifacts from various sources. This study aimed to design a powerful classifier with a strong generalization capability for MI based BCIs.

APPROACH

In this study, we proposed a cluster decomposing based ensemble learning framework (CDECL) for EEG classification of MI based BCIs. The EEG data was decomposed into sub-data sets with different distributions by clustering decomposition. Then a set of heterogeneous classifiers was trained on each sub-data set for generating a diversified classifier search space. To obtain the optimal classifier combination, the ensemble learning was formulated as a multi-objective optimization problem and a stochastic fractal based binary multi-objective fruit fly optimization algorithm was proposed for solving the ensemble learning problem.

MAIN RESULTS

The proposed method was validated on two public EEG datasets (BCI Competition IV datasets IIb and BCI Competition IV dataset IIa) and compared with several other competing classification methods. Experimental results showed that the proposed CDECL based methods can effectively construct a diversity ensemble classifier and exhibits superior classification performance in comparison with several competing methods.

SIGNIFICANCE

The proposed method is promising for improving the performance of MI-based BCIs.