Spinal Cord Injury
Conditions
Keywords
walking, locomotion, rehabilitation
Brief summary
Powered exoskeletons have emerged recently, promising to offer walking to individuals with severe spinal cord injury who are unable to walk. We will use the ReWalk exoskeleton to train walking in individuals with chronic, severe spinal cord injury (SCI). We will determine the characteristics of individuals who most benefit from such training, and identify the neuroplasticity induced by the training. We will further determine the feasibility of the ReWalk for home and community ambulation.
Detailed description
A prospective, pilot, cohort study design will recruit participants to train intensively for a 3 month period. The training sessions will be documented in detail, including number of steps taken, speed of walking, distance of walking. Once walking speed has plateaued, we will evaluate the feasibility of using the device in a home-like environment and in the community. At the end of this study, we will have a good idea of the capability of the ReWalk to assist walking in those with severe spinal cord injury. We will better understand which individuals are most likely to benefit from the ReWalk. We will know how training in the ReWalk changes the neural connections between the brain and the spinal cord so that we can better guide the training protocol. Finally, we will identify limitations of the ReWalk for home and community use, so that exoskeletons can be improved in the future to maximize their benefit to people with spinal cord injury.
Interventions
DEVICEReWalk
Intensive training with the ReWalk to negotiate smooth ground, rough terrain indoors and outdoors, ascending and descending slopes and steps, in a home setting and in the community.
Sponsors
University of Alberta
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* non-progressive spinal cord injury ≥1 year post-injury * Body height between 5'3 and 6'4 * Body weight ≤82 kg * Uses wheelchair as primary mode of mobility * If able to walk, walks at ≤0.4 m/s * Arm strength sufficient to control forearm crutches * Agree to attend intensive training of 1.5 hr/day, 4 days/wk for 14 weeks, plus testing pre and post training of approximately 2 weeks each
Exclusion criteria
* Contractures at the hip, knee or ankle that interferes with fitting into the ReWalk * Fractures within the last 2 years * Osteoporosis in the legs (t-score ≤-3.0) * Severe postural hypotension * Severe spasticity that interferes with use of the ReWalk * Active pressure sores * Pregnancy * Severe head injury * Conditions that preclude intensive exercise (such as high blood pressure) * Presence of conditions contraindicated for transcranial magnetic stimulation
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Physiological Cost Index (PCI) Ratio | End of training:12-14 weeks from baseline | PCI is defined as the change in heart rate from the average at rest to the average in the last two minutes of the 6 minute walk test is divided by the average speed during the last two minutes of walking to give a measure of heartbeats/minute. The ratio between this measure while walking in the Rewalk and the same measure while performing the test using a wheelchair will be calculated. (Walk/wheelchair) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| 10 Meter Walk Test | End of training (at 12 weeks for 10 participants and 6 weeks for 1) and at follow-up (2-3 months from end of training) | Walking is timed over a 10 m section while the participant walks in the ReWalk in a 40 m hallway at the fastest safe speed possible. |
| Max Distance | End of training:12-14 weeks from baseline | The maximum distance walked without a rest for up to one hour. |
| Limits of Stability - Sitting | Baseline, Mid point-6 weeks from baseline, End training:12-14 weeks from baseline | While sitting/standing on a force plate, the participant will lean in 8 directions guided by a computer screen with feedback of the center of pressure. The sum of the maximum fore-aft and left right excursions was calculated. The changes from baseline to mid point of training, the end of the training phase (12 weeks) were calculated. |
| Sitting Sway | Baseline, Mid-point:6 weeks from baseline, End training:12-14 weeks from baseline | Participants will sit on a force plate with feet unsupported, arms crossed over the chest and eyes closed. The trajectory of the center of pressure is measured for a maximum of 30 seconds or until balance is lost. |
| McGill Pain Questionnaire | Baseline, midpoint:6 weeks from baseline, end training:12-14 weeks from baseline | Paper/pencil questionnaire in which participant selects words that describe current pain. Words are divide into 20 subgroups and ranked within each group. A total score is tabulated by adding the number associated with the highest ranking word from each subgroup. Score range is from 0 to 73 with higher scores indicating greater pain. |
| Spinal Cord Assessment Tool for Spastic Reflexes (SCATS) | Baseline, midpoint:6 weeks from baseline, end training:12-14 weeks from baseline | Response to 3 standardized tests: stretch of ankle plantarflexors, pin prick to the sole of the foot, stretch of the hip and knee flexors scored from 1 to 3. The scores form both lower extremities were summed (total score: no spasticity = 0; maximum spasticity = 36 |
| Motor Evoked Potentials | Baseline, End training:12-14 weeks from baseline | Single pulse transcranial magnetic stimulation is delivered over the vertex to induce motor evoked potentials in the back extensor muscles. Electrical responses in paraspinal muscles were recorded at 8 levels spanning the injury. The peak to peak amplitude of the response was averaged over rials with background muscle contraction of 10 to 40 microvolts |
| Change From Baseline in Manual Muscle Test at End of Training | Baseline, end training:12 -14 weeks from baseline | Five muscle groups in each lower extremity (hip flexors, knee extensors, ankle dorsiflexors, extensor of the big toe, and ankle plantarflexors) were tested as per the American Spinal Injury Association Impairment scale. Each muscle group was scored on a scale ranging from 0-5, where 0/5 indicates no muscle activity and is the lowest score and is considered to be a worse outcome. A score of 5/5 indicates normal strength and is considered the better outcome. The scores for all 10 muscle groups were summed so that the maximum score is 50. Change from baseline in Manual Muscle Test to end of training was calculated. 0= total paralysis 1. palpable or visible contraction 2. active movement, gravity eliminated 3. active movement, against gravity 4. active movement, against some resistance 5. active movement, against full resistance |
Countries
Canada
Participant flow
Recruitment details
Participants were recruited from May 2014 to September 26, 2018. Recruitment was through previous contacts, word of mouth and SCI Alberta newsletter.
Participants by arm
| Arm | Count |
|---|---|
| ReWalk Training ReWalk exoskeleton training: 1.5 hr/day, 4 days/week, for 12-14 weeks (approximately 50 training sessions). Participants will progress through the following: sit-to-stand, stand-to-sit, standing balance and weight shift, walking on smooth ground, stopping, turning while walking, walking on rough ground, ascending and descending slopes, ascending and descending steps and curbs. | 11 |
| Total | 11 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Overall Study | Withdrawal by Subject | 2 |
Baseline characteristics
| Characteristic | ReWalk Training | — |
|---|---|---|
| Age, Continuous | 37.5 years STANDARD_DEVIATION 13.7 | — |
| Race and Ethnicity Not Collected | — | — Participants |
| Region of Enrollment Canada | 11 participants | — |
| Sex: Female, Male Female | 4 Participants | — |
| Sex: Female, Male Male | 7 Participants | — |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 12 |
| other Total, other adverse events | 5 / 12 |
| serious Total, serious adverse events | 0 / 12 |
Outcome results
Primary
Physiological Cost Index (PCI) Ratio
PCI is defined as the change in heart rate from the average at rest to the average in the last two minutes of the 6 minute walk test is divided by the average speed during the last two minutes of walking to give a measure of heartbeats/minute. The ratio between this measure while walking in the Rewalk and the same measure while performing the test using a wheelchair will be calculated. (Walk/wheelchair)
Time frame: End of training:12-14 weeks from baseline
Population: Participants who completed 12 weeks of training intervention
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| ReWalk Training | Physiological Cost Index (PCI) Ratio | 3.34 unit less | Standard Deviation 1.75 |
Secondary
10 Meter Walk Test
Walking is timed over a 10 m section while the participant walks in the ReWalk in a 40 m hallway at the fastest safe speed possible.
Time frame: End of training (at 12 weeks for 10 participants and 6 weeks for 1) and at follow-up (2-3 months from end of training)
Population: All participants who completed \>6 weeks of training
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| ReWalk Training | 10 Meter Walk Test | End of training | 0.41 meters/second | Standard Deviation 0.12 |
| ReWalk Training | 10 Meter Walk Test | Follow-up | 0.42 meters/second | Standard Deviation 0.1 |
Secondary
Change From Baseline in Manual Muscle Test at End of Training
Five muscle groups in each lower extremity (hip flexors, knee extensors, ankle dorsiflexors, extensor of the big toe, and ankle plantarflexors) were tested as per the American Spinal Injury Association Impairment scale. Each muscle group was scored on a scale ranging from 0-5, where 0/5 indicates no muscle activity and is the lowest score and is considered to be a worse outcome. A score of 5/5 indicates normal strength and is considered the better outcome. The scores for all 10 muscle groups were summed so that the maximum score is 50. Change from baseline in Manual Muscle Test to end of training was calculated. 0= total paralysis 1. palpable or visible contraction 2. active movement, gravity eliminated 3. active movement, against gravity 4. active movement, against some resistance 5. active movement, against full resistance
Time frame: Baseline, end training:12 -14 weeks from baseline
Population: Participants who completed 12 weeks of training
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| ReWalk Training | Change From Baseline in Manual Muscle Test at End of Training | 0.4 units on a scale | Standard Deviation 1.2 |
Secondary
Limits of Stability - Sitting
While sitting/standing on a force plate, the participant will lean in 8 directions guided by a computer screen with feedback of the center of pressure. The sum of the maximum fore-aft and left right excursions was calculated. The changes from baseline to mid point of training, the end of the training phase (12 weeks) were calculated.
Time frame: Baseline, Mid point-6 weeks from baseline, End training:12-14 weeks from baseline
Population: Participants able to sit unsupported at baseline and 12 weeks of training
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| ReWalk Training | Limits of Stability - Sitting | Change at midpoint | 1.6 cm | Standard Deviation 2.6 |
| ReWalk Training | Limits of Stability - Sitting | Change at end of training | 4.5 cm | Standard Deviation 4.1 |
Secondary
Max Distance
The maximum distance walked without a rest for up to one hour.
Time frame: End of training:12-14 weeks from baseline
Population: Participants who completed 12 weeks of training
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| ReWalk Training | Max Distance | 1309 meters | Standard Deviation 457 |
Secondary
McGill Pain Questionnaire
Paper/pencil questionnaire in which participant selects words that describe current pain. Words are divide into 20 subgroups and ranked within each group. A total score is tabulated by adding the number associated with the highest ranking word from each subgroup. Score range is from 0 to 73 with higher scores indicating greater pain.
Time frame: Baseline, midpoint:6 weeks from baseline, end training:12-14 weeks from baseline
Population: Participants with neuropathic pain at baseline
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| ReWalk Training | McGill Pain Questionnaire | End training | 11.1 score on a scale | Standard Deviation 5.6 |
| ReWalk Training | McGill Pain Questionnaire | Baseline | 14.4 score on a scale | Standard Deviation 11.4 |
| ReWalk Training | McGill Pain Questionnaire | Midpoint | 16.2 score on a scale | Standard Deviation 11.7 |
Secondary
Motor Evoked Potentials
Single pulse transcranial magnetic stimulation is delivered over the vertex to induce motor evoked potentials in the back extensor muscles. Electrical responses in paraspinal muscles were recorded at 8 levels spanning the injury. The peak to peak amplitude of the response was averaged over rials with background muscle contraction of 10 to 40 microvolts
Time frame: Baseline, End training:12-14 weeks from baseline
Population: Participants with adequate background emg
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| ReWalk Training | Motor Evoked Potentials | End training | 353 microvolts | Standard Deviation 118 |
| ReWalk Training | Motor Evoked Potentials | Baseline | 402 microvolts | Standard Deviation 193 |
Secondary
Sitting Sway
Participants will sit on a force plate with feet unsupported, arms crossed over the chest and eyes closed. The trajectory of the center of pressure is measured for a maximum of 30 seconds or until balance is lost.
Time frame: Baseline, Mid-point:6 weeks from baseline, End training:12-14 weeks from baseline
Population: Participants able to sit unsupported for greater than 22 seconds at baseline and after 12 weeks of training
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| ReWalk Training | Sitting Sway | Change at midpoint | -1.59 cm/s | Standard Deviation 1.85 |
| ReWalk Training | Sitting Sway | Change at end training | -1.38 cm/s | Standard Deviation 1.38 |
Secondary
Spinal Cord Assessment Tool for Spastic Reflexes (SCATS)
Response to 3 standardized tests: stretch of ankle plantarflexors, pin prick to the sole of the foot, stretch of the hip and knee flexors scored from 1 to 3. The scores form both lower extremities were summed (total score: no spasticity = 0; maximum spasticity = 36
Time frame: Baseline, midpoint:6 weeks from baseline, end training:12-14 weeks from baseline
Population: Participants measured weekly for 12 weeks. P1 and P2 were measured only at baseline, 6 weeks and 12 weeks of training. P5 withdrew after 6 weeks of training
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| ReWalk Training | Spinal Cord Assessment Tool for Spastic Reflexes (SCATS) | Baseline | 5.91 score on a scale | Standard Deviation 6.17 |
| ReWalk Training | Spinal Cord Assessment Tool for Spastic Reflexes (SCATS) | Midpoint | 5.57 score on a scale | Standard Deviation 4.35 |
| ReWalk Training | Spinal Cord Assessment Tool for Spastic Reflexes (SCATS) | End training | 6.25 score on a scale | Standard Deviation 7.11 |