Effects of Mirror Therapy Combined with EMG-Triggered Functional Electrical Stimulation to Improve on Standing Balance and Gait Ability in Patient with Chronic Stroke
Kim DH, Jang SH. Effects of Mirror Therapy Combined with EMG-Triggered Functional Electrical Stimulation to Improve on Standing Balance and Gait Ability in Patient with Chronic Stroke. International Journal of Environmental Research and Public Health. 2021;18(7):3721. doi:10.3390/ijerph18073721Link to Original Article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8038158/
Key Points
1. The study aimed to evaluate the effects of EMG-triggered functional electrical stimulation (EMG-FES) combined with mirror therapy on balance and gait ability in chronic stroke patients.
2. Sixty chronic stroke patients participated in the study and were divided into three groups: EMG-FES and mirror therapy group, mirror therapy group, and conservative treatment group. Each group underwent specific treatment protocols for eight weeks.
3. The results showed that the EMG-FES and mirror therapy group demonstrated significant improvements in balance and gait ability compared to the mirror therapy and conservative treatment groups.
4. Balance and gait ability were measured using Biorescue, Berg balance scale (BBS), Functional Reach Test (FRT), and 10-meter walk test, and significant improvements were observed in the EMG-FES and mirror therapy group.
5. The study supports the combination of EMG-Triggered functional electrical stimulation and mirror therapy as an effective intervention for improving the balance and gait ability of chronic stroke patients. The findings suggest that this approach can provide stable and effective brain plasticity stimulation for stroke patients requiring long-term treatment.
6. The study was approved by the Institutional Review Board and supported by the National Research Foundation of Korea. Informed consent was obtained from all study participants, and the authors declared no conflicts of interest.
Introduction
The introduction of the research paper discusses the impact of stroke on patients, causing various physical and cognitive impairments that affect their quality of life. It emphasizes the challenges faced by stroke patients related to balance and posture control, as well as the difficulty in improving their balance ability. The paper reviews various methods used for stroke rehabilitation, including dual task exercise, Brunstrom movement therapy, virtual environment rehabilitation, mirror therapy and functional electrical stimulation. The researchers continue by discussing mirror therapy and functional electrical stimulation. The mirror therapy involves reflecting and projecting the motion of a non-injured limb on the paralyzed limb through a mirror. The theory behind mirror therapy is that the images of non-injured limbs stimulate the brain. Functional Electrical Stimulation (FES) is also mentioned. FES uses electrical stimulation to induce muscle contraction on the paralyzed or weakened muscle with the goal of preventing muscle atrophy, maintaining muscle tolerance, strengthening muscles and retaining functional movement. Prior studies have found positive effects of mirror therapy and functional electrical stimulation on stroke patient recovery, but there is a need for further research, particularly in combination interventions. Therefore, the paper aims to investigate the impact of mirror therapy with EMG-Triggered functional electrical stimulation on the balance and gait ability of chronic stroke patients, providing important reference data for improving the rehabilitation of stroke patients.
Methods
Subjects
The study was conducted on chronic stroke patients who met specific selection criteria and agreed to participate. Inclusion criteria include patients who were diagnosed with stroke for the first time for 6 months or more who present without visual or hearing impairments, without cognitive impairment, and able to ambulate independently. Exclusion criteria include patients who present with unilateral neglect, somatosensory deficits, or musculoskeletal damage and degenerative disease that can affect balance and gait. In total, 60 patients met the selection criteria.
Protocol
A total of 60 subjects were randomly divided into three groups: mirror treatment and functional electrical stimulation (MT-FE), mirror treatment (MT), and conservative treatment (CON). Participants underwent training sessions for 60 minutes per day, 5 times per week for 8 weeks, and pre-test and post-test assessments were conducted.
MT-FE Group
Patients in the MT-FE group received conservative therapy 30 minutes per day, 5 times per week for 8 weeks along with mirror therapy in parallel with FES 30 minutes per day, 5 times per week for 8 weeks. During mirror therapy, patients sat down on a chair with a backrest. The injured/paralyzed leg was covered by a mirror with a visual feedback provided by the image of non-paralyzed legs. Patients were given the freedom to perform flexion/extension of the knee joint and ankle joint independently while FES was applied to the paralyzed leg.
MT Group
Patients in the MT group received conservative therapy 30 minutes per day, 5 times per week for 8 weeks along with mirror therapy 30 minutes per day, 5 times per week for 8 weeks. During mirror therapy, patients sat down on a chair with a back rest. The injured/paralyzed leg was covered by a mirror with a visual feedback provided by the image of non-paralyzed legs. Patients were given the freedom to perform flexion/extension of the knee joint and ankle joint independently but FES was not applied to the patient.
CON Group
Patients received active and passive joint movements and stretch, joint mobilization, muscle strengthening exercise, and gait training for 30 minutes per session, 2 sessions per day, 5 times per week for 8 weeks.
Measurement
Biorscue
Biorscue was used to test the patient’s static balance ability as determined by the total travel distance of the center of pressure (COP) on the foot sensor. Patients stood upright with legs open at 30 degrees with head in neutral position for 1 minute. Smaller COP distance meant decreased body sway, indicating a greater static balance ability.
Berg Balance Scale (BBS)
BBS was used to measure the patient’s balance ability in the area of sitting, standing, and posture change. The highest possible score was 56 which indicates good standing balance, while a lower score indicates poor balance.
Functional Reach Test (FRT)
FRT measures a patient’s ability to reach forward without losing his/her standing balance.
10m Walk Test (10 m WT)
Patients ambulated 14 meters in a straight line with the time between 2 meters in the beginning and end were removed due to acceleration and deceleration. The walking time was measured with a stopwatch, and the patients measured three times with the average time of the three trials calculated.
Results
In this study, sixty subjects were randomly assigned to three groups: the mirror therapy with EMG-triggered functional electrical stimulation (MT-FE) group, the mirror therapy (MT) group, and the control (CON) group. There were no significant differences in the general characteristics of the subjects among the three groups. The results depicted in the table illustrate the change in balance and gait ability following the interventions. Significantly, all groups demonstrated improvement within themselves. However, when comparing the groups, the MT-FE group exhibited notably more improvement than the MT group and the control group. This difference was found to be statistically significant (p < 0.05).
Table 2
Comparison pre and post test among three groups (n = 60)
Overall, the findings suggest that both mirror therapy and mirror therapy with EMG-triggered functional electrical stimulation interventions led to significant improvements in balance and gait ability for chronic stroke patients. However, the MT-FE group showed greater improvement compared to the MT and control groups. These results indicate that the application of EMG-triggered functional electrical stimulation in combination with mirror therapy could be a promising approach to enhance balance and gait ability in chronic stroke patients. This has important implications for the development of rehabilitation strategies targeting the improvement of motor function in stroke patients.
Discussion
The study aimed to assess the impact of interventions on the balance and gait ability of chronic stroke patients, specifically looking at the use of combined EMG-Triggered electrical stimulation and mirror therapy. Three groups were included in the study: combined treatment group, mirror treatment group, and conservative treatment group. Balance and gait impairment are common after stroke, and training goals include achieving independent activity and gait. The mirror-neuron system, which enables learning through observation, plays a crucial role in rehabilitating stroke patients.
The study revealed a significant improvement in balance ability in all three groups, with the combined treatment group showing the most significant progress. Similarly, gait ability significantly increased in all groups with the combined treatment group again showing the most substantial improvement. Previous research also supported the positive impact of mirror therapy and functional electrical stimulation on motor function recovery in stroke patients.
However, the study cautioned the limitation of generalizing the results to all stroke patients due to the specific selection criteria of the subjects and the potential influence of their daily activities. The paper also highlighted the need for future studies to explore various aspects such as different mirror therapy training methods, the adaptability of subjects to electrical stimulation, and the use of diverse balance and gait evaluation tools. Additionally, the potential for further research on gait parameters to better understand therapeutic effects was suggested.
Conclusions
The study aimed to examine the impact of combining EMG-Triggered functional electrical stimulation (FES) and mirror therapy on the balance and gait ability of chronic stroke patients. The researchers found that this combined intervention had a positive effect on the balance and gait ability of the participants. Since the restoration of balance and walking ability is crucial for the daily life of chronic stroke patients, these findings hold significance for their rehabilitation. The study indicates that the combination of EMG-Triggered FES and mirror therapy can provide a stable and easily administered method for stimulating brain plasticity in stroke patients. The potential for long-term treatment makes this intervention method particularly significant for stroke patients. Overall, the results suggest that the combined approach of EMG-Triggered FES and mirror therapy holds promise for enhancing the recovery of balance and gait ability in chronic stroke patients, potentially offering a valuable addition to rehabilitation strategies for this patient population.
Opportunities for Future Research
1. Investigate the long-term effects of EMG-triggered functional electrical stimulation combined with mirror therapy on balance and gait ability in chronic stroke patients, particularly focusing on the sustainability of the improvements observed in this study.
2. Explore the potential benefits of combining EMG-triggered functional electrical stimulation and mirror therapy with other rehabilitation methods, such as virtual environment rehabilitation, dual task exercises, or collaborative action of Brunstrom, to identify potential synergistic effects on balance and gait ability in chronic stroke patients.
3. Examine the impact of EMG-triggered functional electrical stimulation and mirror therapy on specific aspects of gait, such as gait speed, stride length, and gait symmetry, to provide a more comprehensive understanding of their effects on gait ability in chronic stroke patients.
4. Investigate the underlying mechanisms of EMG-triggered functional electrical stimulation combined with mirror therapy in improving balance and gait ability, including neuroplasticity, motor cortex reorganization, and the activation of mirror neurons in the brain.
5. Conduct comparative studies to evaluate the cost-effectiveness and practical feasibility of implementing EMG-triggered functional electrical stimulation and mirror therapy in clinical rehabilitation programs for chronic stroke patients, compared to other conventional or innovative rehabilitation approaches.
6. Assess the generalizability of the findings from this study by conducting similar research on larger and more diverse populations of chronic stroke patients, considering factors such as age, gender, stroke severity, and comorbidities that may influence the response to EMG-triggered functional electrical stimulation and mirror therapy.
