This study is a single-blind, parallel, three-group, and randomized controlled trial.
This study aimed to investigate the effectiveness of electrical stimulation-augmented virtual reality training in improving balance in individuals with incomplete spinal cord injury (iSCI).
Individuals with iSCI often face significant balance and mobility impairments affecting their quality of life. Scientific studies focusing on standing balance training in the iSCI population are limited. Virtual reality-based balance training has shown positive results in several neurological populations. Electrical stimulation has also proved to be effective in improving voluntary muscle strength in partially paralyzed muscles after iSCI as well as promoting neuroplasticity.
Forty-eight iSCI participants will be recruited based on the inclusion criteria. The participants will be randomly assigned to any of the three groups: virtual reality-based balance training along with the electrical stimulation group, virtual reality-based balance training along with sham stimulation group, or virtual reality-based balance training group. The intervention will be delivered as 60-minute sessions, thrice a week for 4 weeks.
The performance of the participants will be assessed using the lower extremity motor score, static and dynamic balance assessment using TechnoBody ProKin tilting platform and Berg Balance Scale, Walking Index for Spinal Cord Injury, and World Health Organization Quality of Life-BREF at pre-intervention, after 4 weeks post-intervention, and at 1-month follow-up.
The trial will provide new knowledge about the effectiveness of electrical stimulation-augmented virtual reality training in improving balance in individuals with iSCI. The study results will contribute to the design of better rehabilitation programs for individuals with iSCI.
Spinal cord injury (SCI) is one of the most catastrophic injuries of the nervous system resulting in permanent neurological deficits, functional impairments, and abrupt change in the quality of the person’s life. It may lead to a profound disability with negative physiological, physical, or psychological sequelae and restricted employment opportunities even after the individual has reintegrated into community living [
The recovery of walking function is one of the primary aims of rehabilitative programs in individuals with incomplete SCI (iSCI) [
Research specifying effective balance training protocols for individuals with iSCI is limited. Prior studies have examined the effects of visual feedback [
Rehabilitation methods based on VR have been recently introduced and have shown positive results for balance training in several neurological populations [
Electrical stimulation (ES) has often been used as a therapeutic tool to promote recovery of function following nervous system injury [
The main objective of this study is to investigate the efficacy of ES-augmented VR training protocol for improving lower extremity muscle strength, balance, functional mobility, and quality of life (QOL) in persons with iSCI. A follow-up study 1-month post-intervention shall also be conducted. It is hypothesized that significant improvement in lower extremity muscle strength, balance, functional mobility, and QOL of persons with iSCI will be noticeable after 4 weeks of ES-augmented VR training when compared with participants receiving VR training alone. In addition, these improvements shall be maintained after 1-month post-intervention as well.
A clinical trial is designed to see the efficacy of the protocol on lower extremity muscle strength, balance, functional mobility, and QOL in persons with iSCI.
A single-blind, parallel, three-group, and randomized controlled trial will be undertaken. A purposive sample of 48 participants with iSCI will be recruited from the inpatient and outpatient rehabilitation departments of the Indian Spinal Injuries Centre, New Delhi, India. All participants will be provided with information sheets, and written informed consent will be obtained by an investigator before recruitment. The demographic details will be obtained, and the participants will be selected based on eligibility criteria after the neurological examination (
The participants will be randomly assigned to any of the three groups: virtual reality-based balance training+electrical stimulation (VR-ES) group, virtual reality-based balance training+sham stimulation (VR-SS) group, or virtual reality-based balance training (VR) group for thrice a week for 4 weeks. The recruitment will be over 2 years. This research protocol followed the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) recommendations (SPIRIT schedule) (
All potential trial participants will be informed orally and in writing about the purpose of this trial, its potential risks, costs and benefits of participation, and the right to withdraw before the screening.
A written informed consent would be taken and signed by the participants who are interested for participation in the study. The study protocol has been approved by the institutional review board of the Indian Spinal Injuries Centre and Amity University and registered with the Clinical Trials Registry-India (CTRI/2018/12/016814). Data will be collected, managed, stored, and confidentiality maintained. All authors will have access to the final trial dataset. During the study, the participants shall not be allowed to participate in other rehabilitation or research interventions that can influence the outcome of the study.
Randomization for enrolled participants will be performed by a computer-generated randomization sequence created using the Random Allocation Software by a person other than the principal investigator. The allocation schedule will be sequentially numbered and sealed in opaque envelopes to ensure concealment. Furthermore, a person not associated with the study will sequentially open the numbered envelopes to reveal the participant’s group allocation upon completion of each participant’s assessment. The participants will be assigned to one of the VR-ES, VR-SS, or VR groups.
The outcome assessor will be blinded to group allocation. On the other hand, the principal investigator will be informed of the group allocation given the nature of the interventions. Investigators who will perform data analysis would be unaware of the treatment group.
The intervention program will be divided into three phases (
Participants in the VR-ES group shall also receive ES while performing virtual balance exercises. ES shall be delivered using an eight-channel electrical stimulator that uses surface self-adhesive stimulation electrodes placed on the subject’s skin corresponding to the muscles targeted. The key muscles that shall be targeted are the bilateral quadriceps, hamstrings, dorsiflexors, and plantarflexors. The pulse width is 50 μs and the pulse frequency is 20 Hz. The current levels shall be separately selected for each muscle group such that the participant felt the stimulation without having the stimulated muscles contract due to the stimulation [
Participants randomized to the VR-SS group will be managed identically with the VR-ES group, but the amplitude shall be set at 0 mA so no ES shall occur while performing balance exercises on the Nintendo Wii. The participants shall be told before treatment that they may or may not feel the stimulation to promote a similar mental setup. Those in the VR group shall not receive any form of ES while performing virtual balance exercises.
The initial difficulty of the exercises shall be adjusted for each participant based on their performance during the familiarization session. The difficulty level of a game will be gradually increased to require more multidirectional movement in the center of the mass. The levels will be progressed when the participant reaches at least a 95% success rate in three rounds. The participants will receive a concomitant visual and auditory knowledge of the results of the success of the task when movements are accurately made within a specified time because learning is also affected by performance-related feedback. On the other hand, participants will also receive negative knowledge of the performance of the use of compensatory strategies while performing games using the Wii Fit.
The adherence of the participants to the training protocol will be monitored through documentation of session attendance, length, and activities. Participants in all groups shall receive VR-based balance training exercises which may positively influence adherence and reduce attrition rates because all groups are likely to feel engaged in an active intervention. The participants would be permitted to increase the training duration by 1 week keeping in mind the “intention-to-treat” principle if the participants will be unable to complete the total number of sessions within the stipulated 4 weeks. The participants will be monitored through regular telephonic reminders to ensure compliance in the follow-up. For missing data during follow-up, the principle of the “last observation carried forward” shall be applied, wherein the missing final values of the outcome variable are replaced by the last known value before the participant is lost to follow-up [
The lower extremity motor score (LEMS), a subscale of the American Spinal Injury Association classification, is the sum of the bilateral lower extremity key muscle power, ranging from total paralysis (0) to normal active movement with a full range of motion against gravity and full resistance (5) with a total possible score of 50 [
ProKin tilting platform (ProKin PK254; TechnoBody Inc., Dalmine, Italy) will be used for the measurement of postural stability indexes. The TechnoBody is a monoaxial platform that consists of three strain gauges that are placed under a circular surface of 55 cm in diameter and have a 20-Hz sampling frequency. Participants will be tested with two levels of postural difficulty including double-leg standing with opened and closed eyes. Participants will be instructed to stand still, barefoot with arms at side and feet 10 cm apart, look at a screen in front of them, and not to talk during the test [
The Berg Balance Scale (BBS) is a clinical measure of balance consisting of 14 tasks of progressing difficulty, each graded on a five-point ordinal scale and then summed up to obtain a total score ranging from 0 to 56. Scoring is based on the ability to meet a certain time or distance requirement and to perform the items without assistance. The participants shall wear their usual shoes and braces, if necessary, during testing. Assessments will be conducted without the participants’ walking assistive devices [
The Walking Index for Spinal Cord Injury (WISCI) II is a walking assessment comprising of 21 levels representing a gradation of walking performance based on the need for physical assistance, braces, and walking aids. WISCI II ranges from 0 to 20. The maximal level at which a person will be able to walk safely shall be recorded. Moreover, it has been reported to have excellent reproducibility (ICC, 0.995) and inter- and intra-rater reliability (1.00) in the SCI population [
The World Health Organization Quality of Life-BREF (WHOQOL-BREF) is a 26-item instrument consisting of four domains (physical health, psychological health, social, and environmental) and two overall QOL and general health items. Respondents rated the intensity, frequency, or evaluation of the selected attributes of QOL during the previous 2 weeks on a 5-point Likert-response scale. The mean score in each domain will be obtained by computing the mean of transformed scores converted to a 0–100 scale for each domain. A mean score of <40, 41–60, and >60 in each domain denoted poor, moderate, and good QOL, respectively. All domains of the WHOQOL-BREF have been reported to show good internal consistency (Cronbach α range, 0.74–0.78) except for the social relationships domain (α=0.54) in individuals with SCI [
Sample size estimation was done to test the improvements in the outcome measures in each of the three groups. An a priori sample size estimation was performed using the G*Power 3 software (v3.1.2–3.1.9; Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany;
The Student
Descriptive data will be exposed as means or proportions along with standard deviations. Continuous variables will be summarized as mean±standard deviation for normal distribution and median±interquartile range for non-normal distribution. The Shapiro-Wilk test will be used to ensure the normal distribution of data. For the variables with a normal distribution, outcomes between groups across periods will be compared using the 3×3 mixed-model analysis of variance. The intragroup comparison will be analyzed by paired Student
The performance of the participants will be assessed on LEMS, and the static and dynamic balance assessment using the TechnoBody ProKin tilting platform and BBS, WISCI, and World Health Organization QOL-BREF at pre-intervention, after 4 weeks post-intervention, and 1-month follow-up.
The recovery of balance during standing is one of the primary and essential aims of rehabilitative programs in individuals with iSCI. Retraining standing balance is challenging for healthcare professionals dealing with SCI. The trial will provide information about the effectiveness of ES-augmented VR training in improving balance in persons with iSCI. It is believed that the results of this training will help to improve lower extremity muscle strength, balance, functional mobility, and QOL in persons with iSCI. Previous studies have identified the limitation of transfer of the gains acquired in the virtual balance task during the training session to the performance of tests of balance and stability outside the context of the trained task conditions [
This trial is designed to meet the methodological demand for adequate randomization, allocation concealment, and blinding of outcome assessors and statisticians. The trial will be reported according to the CONSORT guidelines. A limitation of this trial is that it will be a single-blinded trial (assessor only) due to the nature of the intervention. The recruitment of the participants shall be done through a convenience sample from one rehabilitation center in New Delhi. This may result in a possible selection bias.
This protocol will help determine the efficacy of ES-augmented VR training protocol for improving standing balance and functional mobility in persons with iSCI. This is one of the few protocols which have been designed specifically for iSCI. Thus, it is believed that this protocol will result in substantial improvement in standing balance in individuals with incomplete SCI despite the limitations.
No potential conflict of interest relevant to this article was reported.
SW, PK, and CK conceived the idea for the study. All authors contributed to the design and development of the study. SW drafted the manuscript. All authors have critically reviewed and approved the final manuscript.
CONSORT (Consolidated Standards of Reporting Trials) flowchart. VR-ES group, virtual reality-based balance training along with electrical stimulation; VR-SS group, virtual reality-based balance training along with sham stimulation; VR group, virtual reality-based balance training only.
Eligibility criteria
Criteria | |
---|---|
Inclusion criteria | Traumatic or non-traumatic spinal cord injury categorized as American Spinal Injury Association Impairment Scale grade C or D since at least 6 months |
Level of injury from C5 to L1 | |
Age between 18–45 years | |
Able to stand with or without the support of an assistive device for a minimum of 2 minutes | |
Willing to participate in the study | |
Mini-Mental Status Examination scores ≥24 | |
Exclusion criteria | Spinal shock |
Any other pre-existing neurological problem, musculoskeletal condition, or psychiatric problem which may interfere with the treatment | |
Pain scored greater than 5 on an 11-point numerical rating pain scale (0, no pain; 10, most severe pain) | |
Any other pre-existing recent complication that can interfere with participation | |
Symptoms of orthostatic hypotension upon standing | |
Severe depression (Beck Depression Inventory-II ≥29) | |
Spasticity of grade 3 or more on Modified Ashworth Scale | |
Visual or auditory impairment such that it impacts on the ability to participate | |
Additional exclusion criteria for ES group includes contraindications for ES such as: (1) cardiac pacemakers; (2) skin lesions or rash at potential sites; (3) grade 4 pressure ulcers anywhere on the lower extremities according to the National Pressure Ulcer Advisory Panel classification; and (4) grade 2 or 3 pressure ulcers according to the National Pressure Ulcer Advisory Panel classification at locations where ES is to be applied. |
ES, electrical stimulation.
Schedule of enrollment, interventions, and assessments according to the Standard Protocol Items: Recommendations for Interventional Trials guideline
VR-ES group, virtual reality-based balance training along with electrical stimulation; VR-SS group, virtual reality-based balance training along with sham stimulation; VR group, virtual reality-based balance training only.
Details of intervention in each group
Intervention phase | Details of intervention |
---|---|
Phase 1 (15 min) | Kinesiotherapy: stretching, free exercises, light resistance exercises, and postural adjustments followed by joint mobility |
Phase 2 (30 min) | |
VR-ES group | Virtual reality-based balance training by the Wii Fit Plus software and Wii Fit balance board system + electrical stimulation on bilateral quadriceps, hamstrings, dorsiflexors, and plantarflexors |
VR-SS group | Virtual reality-based balance training by the Wii Fit Plus software and Wii Fit balance board system + sham stimulation |
VR group | Virtual reality-based balance training by the Wii Fit Plus software and Wii Fit balance board system |
Phase 3 (15 min) | Learning transfer activities: participants to perform real-world exercises that included movements based on those practiced while engaging in virtual reality tasks, such as: weight shifting in the left and right directions and then progressing to forward and backward weight shifting (resembling penguin slide) while standing in front of the mirror placed 2 m away, straight line walking (resembling tightrope), and heading a ball thrown at them by the therapist in various directions (resembling soccer heading). |
VR-ES group, virtual reality-based balance training along with electrical stimulation; VR-SS group, virtual reality-based balance training along with sham stimulation; VR group, virtual reality-based balance training only.
Description of games using Wii Fit
Game | General description | Therapeutic goals |
---|---|---|
Tightrope walking | Standing on a Wii balance board, subject shifts weight from side to side to mimic walking in place. Player must jump over obstacles by slightly extending knees while maintaining balance. | Weight shift to left and right for dynamic balance attention and coordination; motor response; visual and auditory feedback |
Soccer heading | Standing on a Wii balance board, subjects move their weight in the direction in which a ball is flying. The avatar heads the ball. Attention is paid to avoid hitting objects that are not balls. | Weight shift to left and right for dynamic balance attention and coordination; motor response; visual and auditory feedback |
Penguin slide | Standing on a Wii balance board, subjects with slight knee flexion shift their body left and right to catch as many fish as possible without falling off the iceberg. | Weight shift to left and right for dynamic balance postural control; attention and coordination; visual and auditory feedback |
Balance bubble | Standing on the Wii balance board, subject navigates down the river in a bubble by weight shifting in all planes. The participant has to avoid being hit by walls, rocks, and stinging bee. | Weight shift to left and right+forward and backward for dynamic balance postural control; attention and coordination; visual and auditory feedback |
Table tilt | Standing on the Wii balance board, subjects guide balls into holes by shifting left, right, forward, and backward. Platform tilts along with the players movement. | Weight shift in multiple directions for dynamic balance postural control; attention and coordination; visual and auditory feedback |