A Novel Mechanics-based Intervention to Improve Post-stroke Stability
Study Details
Study Description
Brief Summary
The purpose of this study is to determine whether a novel treadmill training intervention can improve the gait stabilization strategy used by individuals who have experienced a stroke.
Condition or Disease | Intervention/Treatment | Phase |
---|---|---|
|
N/A |
Detailed Description
Every year, approximately 15,000 American Veterans experience a stroke, with an estimated cost of acute and follow-up care in the hundreds of millions of dollars. Following a stroke, the restoration or improvement of walking is a high-ranking goal among patients, but only about half of the population is able to return to typical levels of community ambulation. The resultant decrease in independent mobility is strongly associated with a decline in quality of life. Gait instability is a common contributor to limited mobility through either an increased fall-risk or fear of falling, but current interventions to address post-stroke gait instability have had limited success. This project will conduct initial testing of a novel elastic force-field designed to improve post-stroke gait stability through targeted motor learning. The results of these experiments will serve as the basis for the development of novel gait rehabilitation techniques, which have the potential to increase the quality of life of thousands of Veterans and save millions of dollars.
Study Design
Arms and Interventions
Arm | Intervention/Treatment |
---|---|
Experimental: Error reduction Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error reduction" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. |
Behavioral: Error reduction
During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs toward mechanically-appropriate mediolateral locations, having the effect of reducing the errors in foot placement that are often present among individuals who have experienced a stroke.
|
Experimental: Error augmentation Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error augmentation" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. |
Behavioral: Error augmentation
During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs away from mechanically-appropriate mediolateral locations, having the effect of amplifying the errors in foot placement that are often present among individuals who have experienced a stroke.
|
Sham Comparator: Activity matched control Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "transparent" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. |
Behavioral: Activity matched control
During training sessions, participants will interface with a custom-built force-field while they walk. The force-field will essentially get out of the way, producing minimal forces on the legs, and having no direct effect on the errors in foot placement that are often present among individuals who have experienced a stroke.
|
Outcome Measures
Primary Outcome Measures
- Partial Correlation Between Pelvis Displacement and Paretic Step Width During Gait (Change From Baseline) [baseline, 4-weeks, 8-weeks, 12-weeks, 24-weeks]
A custom measure that quantifies the strength of the relationship between body mechanics and foot placement. This measure falls within a relatively narrow range among neurologically intact controls, but is substantially reduced in some individuals who have experienced a stroke, indicating a reduced ability to stabilize their gait pattern. This measure relates the mechanical state of the body at the start of each step (mediolateral pelvis displacement and velocity of the pelvis relative to the stance foot) to the step width at the end of the step. Specifically, the partial linear correlation between pelvis displacement and step width was calculated, accounting for variation in pelvis velocity. The change in this measure relative to baseline is calculated at four time points (after 4, 8, 12, and 24 weeks).
Secondary Outcome Measures
- Functional Gait Assessment (Change From Baseline) [baseline, 4-weeks, 8-weeks, 12-weeks, 24-weeks]
A commonly-used clinical test to quantify balance and stability during various walking tasks. The minimum value is 0, the maximum value is 30, and higher scores indicate better outcomes. The total maximum value of 30 is calculated as the sum of 10 subscores, each of which has a scoring range of 0-3 and represents a distinct walking task. The change in this measure relative to baseline is calculated at four time points (after 4, 8, 12, and 24 weeks).
- Activities-specific Balance Confidence Scale (Change From Baseline) [baseline, 4-weeks, 8-weeks, 12-weeks, 24-weeks]
A commonly-used clinical scale that quantifies an individual's confidence in performing various tasks requiring balance. The minimum value is 0, the maximum value is 100, and higher scores indicate a better outcome. The overall score is calculated as the mean of 16 subscores, each of which can range of 0 to 100 and represents self-efficacy at a distinct movement task. The change in this measure relative to baseline is calculated at four time points (after 4, 8, 12, and 24 weeks).
- 10-meter Walk Test (Change From Baseline) [baseline, 4-weeks, 8-weeks, 12-weeks, 24-weeks]
A commonly-used clinical test to quantify general gait function. Walking speed is measured during the middle 6-meter portion of a 10-meter straight line path. The change in this measure relative to baseline is calculated at four time points (after 4, 8, 12, and 24 weeks).
- Fall Incidence [6 months (during 12 week follow-up period)]
Self-report history of fall occurrence, quantified by the average number of falls per participant in each group during the 12-week period that followed completion of the study's intervention component
- Fear of Falling [6 months (at completion of 12-week Follow-up period)]
Self-report statement of whether a participant has a fear of falling
Eligibility Criteria
Criteria
Inclusion Criteria:
-
At least 21 years old
-
Experience of a stroke 6 months prior to participation
-
Preferred overground gait speed of at least 0.2 m/s
-
Ability to walk at self-selected speed for 3 minutes without a cane or walker
-
Provision of informed consent.
Exclusion Criteria:
-
Resting heart rate above 110 beats/min
-
Resting blood pressure higher than 200/110 mm Hg
-
History of congestive heart failure, unstable cardiac arrhythmias, hypertrophic cardiomyopathy, severe aortic stenosis, angina or dyspnea at rest or during activities of daily living
-
Preexisting neurological disorders or dementia
-
History of major head trauma
-
Legal blindness or severe visual impairment
-
Life expectancy <1 yr; 8)
-
History of deep vein thrombosis or pulmonary embolism within 6 months
-
Uncontrolled diabetes with recent weight loss, diabetic coma, or frequent insulin reactions
-
Orthopedic injuries or conditions (e.g. joint replacements) in the lower extremities with the potential to alter the gait pattern.
Contacts and Locations
Locations
Site | City | State | Country | Postal Code | |
---|---|---|---|---|---|
1 | Ralph H. Johnson VA Medical Center, Charleston, SC | Charleston | South Carolina | United States | 29401-5799 |
Sponsors and Collaborators
- VA Office of Research and Development
Investigators
- Principal Investigator: Jesse C. Dean, PhD, Ralph H. Johnson VA Medical Center, Charleston, SC
Study Documents (Full-Text)
More Information
Publications
None provided.- N2256-R
- RX002256
Study Results
Participant Flow
Recruitment Details | Participants were recruited and enrolled between February 2017 and October 2019 from a database housed at the Medical University of South Carolina. Individuals in this database had previously experienced a stroke, and had agreed to be contacted for participation in research studies. |
---|---|
Pre-assignment Detail | Of the 93 participants who were assessed for eligibility, 54 met the study's inclusion criteria and were interested in participating in the intervention. These 54 participants were randomized to one of the three study arms. |
Arm/Group Title | Error Reduction | Error Augmentation | Activity Matched Control |
---|---|---|---|
Arm/Group Description | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error reduction" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error reduction: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs toward mechanically-appropriate mediolateral locations, having the effect of reducing the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error augmentation" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error augmentation: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs away from mechanically-appropriate mediolateral locations, having the effect of amplifying the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "transparent" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Activity matched control: During training sessions, participants will interface with a custom-built force-field while they walk. The force-field will essentially get out of the way, producing minimal forces on the legs, and having no direct effect on the errors in foot placement that are often present among individuals who have experienced a stroke. |
Period Title: Overall Study | |||
STARTED | 18 | 18 | 18 |
Received Allocated Intervention | 15 | 17 | 14 |
COMPLETED | 14 | 17 | 13 |
NOT COMPLETED | 4 | 1 | 5 |
Baseline Characteristics
Arm/Group Title | Error Reduction | Error Augmentation | Activity Matched Control | Total |
---|---|---|---|---|
Arm/Group Description | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error reduction" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error reduction: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs toward mechanically-appropriate mediolateral locations, having the effect of reducing the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error augmentation" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error augmentation: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs away from mechanically-appropriate mediolateral locations, having the effect of amplifying the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "transparent" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Activity matched control: During training sessions, participants will interface with a custom-built force-field while they walk. The force-field will essentially get out of the way, producing minimal forces on the legs, and having no direct effect on the errors in foot placement that are often present among individuals who have experienced a stroke. | Total of all reporting groups |
Overall Participants | 18 | 18 | 18 | 54 |
Age (years) [Mean (Standard Deviation) ] | ||||
Mean (Standard Deviation) [years] |
64
(13)
|
57
(13)
|
57
(14)
|
59
(14)
|
Sex: Female, Male (Count of Participants) | ||||
Female |
9
50%
|
6
33.3%
|
9
50%
|
24
44.4%
|
Male |
9
50%
|
12
66.7%
|
9
50%
|
30
55.6%
|
Ethnicity (NIH/OMB) (Count of Participants) | ||||
Hispanic or Latino |
0
0%
|
0
0%
|
0
0%
|
0
0%
|
Not Hispanic or Latino |
18
100%
|
18
100%
|
18
100%
|
54
100%
|
Unknown or Not Reported |
0
0%
|
0
0%
|
0
0%
|
0
0%
|
Race (NIH/OMB) (Count of Participants) | ||||
American Indian or Alaska Native |
0
0%
|
1
5.6%
|
0
0%
|
1
1.9%
|
Asian |
0
0%
|
0
0%
|
0
0%
|
0
0%
|
Native Hawaiian or Other Pacific Islander |
0
0%
|
0
0%
|
0
0%
|
0
0%
|
Black or African American |
6
33.3%
|
7
38.9%
|
8
44.4%
|
21
38.9%
|
White |
12
66.7%
|
10
55.6%
|
10
55.6%
|
32
59.3%
|
More than one race |
0
0%
|
0
0%
|
0
0%
|
0
0%
|
Unknown or Not Reported |
0
0%
|
0
0%
|
0
0%
|
0
0%
|
Affected leg (Count of Participants) | ||||
Left leg |
10
55.6%
|
9
50%
|
10
55.6%
|
29
53.7%
|
Right leg |
8
44.4%
|
9
50%
|
8
44.4%
|
25
46.3%
|
Time since stroke (months) [Mean (Standard Deviation) ] | ||||
Mean (Standard Deviation) [months] |
53
(48)
|
53
(46)
|
56
(57)
|
54
(50)
|
Height (inches) [Mean (Standard Deviation) ] | ||||
Mean (Standard Deviation) [inches] |
66
(4)
|
68
(4)
|
67
(4)
|
67
(4)
|
Weight (pounds) [Mean (Standard Deviation) ] | ||||
Mean (Standard Deviation) [pounds] |
187
(49)
|
189
(44)
|
181
(39)
|
186
(43)
|
Partial Correlation Between Pelvis Displacement and Paretic Step Width During Gait (Correlation Coefficient) [Mean (Standard Deviation) ] | ||||
Mean (Standard Deviation) [Correlation Coefficient] |
0.44
(0.10)
|
0.34
(0.19)
|
0.51
(0.10)
|
0.43
(0.16)
|
Functional Gait Assessment (Score on a scale) [Mean (Standard Deviation) ] | ||||
Mean (Standard Deviation) [Score on a scale] |
15.5
(3.2)
|
13.8
(5.2)
|
13.5
(5.0)
|
14.3
(4.6)
|
Activities-specific Balance Confidence scale (Score on a scale) [Mean (Standard Deviation) ] | ||||
Mean (Standard Deviation) [Score on a scale] |
65.7
(22.2)
|
69.8
(12.4)
|
69.3
(15.3)
|
68.3
(16.6)
|
Walking speed (10-meter walk test) (meters per second) [Mean (Standard Deviation) ] | ||||
Mean (Standard Deviation) [meters per second] |
0.84
(0.21)
|
0.73
(0.31)
|
0.78
(0.31)
|
0.78
(0.28)
|
Fall incidence (self reported over previous year) (Count of Participants) | ||||
Count of Participants [Participants] |
6
33.3%
|
7
38.9%
|
7
38.9%
|
20
37%
|
Fear of falling (self-reported) (Count of Participants) | ||||
Count of Participants [Participants] |
5
27.8%
|
7
38.9%
|
4
22.2%
|
16
29.6%
|
Outcome Measures
Title | Partial Correlation Between Pelvis Displacement and Paretic Step Width During Gait (Change From Baseline) |
---|---|
Description | A custom measure that quantifies the strength of the relationship between body mechanics and foot placement. This measure falls within a relatively narrow range among neurologically intact controls, but is substantially reduced in some individuals who have experienced a stroke, indicating a reduced ability to stabilize their gait pattern. This measure relates the mechanical state of the body at the start of each step (mediolateral pelvis displacement and velocity of the pelvis relative to the stance foot) to the step width at the end of the step. Specifically, the partial linear correlation between pelvis displacement and step width was calculated, accounting for variation in pelvis velocity. The change in this measure relative to baseline is calculated at four time points (after 4, 8, 12, and 24 weeks). |
Time Frame | baseline, 4-weeks, 8-weeks, 12-weeks, 24-weeks |
Outcome Measure Data
Analysis Population Description |
---|
The total of 44 participants analyzed corresponds to the participants who completed the intervention and follow-up assessment. |
Arm/Group Title | Error Reduction | Error Augmentation | Activity Matched Control |
---|---|---|---|
Arm/Group Description | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error reduction" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error reduction: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs toward mechanically-appropriate mediolateral locations, having the effect of reducing the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error augmentation" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error augmentation: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs away from mechanically-appropriate mediolateral locations, having the effect of amplifying the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "transparent" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Activity matched control: During training sessions, participants will interface with a custom-built force-field while they walk. The force-field will essentially get out of the way, producing minimal forces on the legs, and having no direct effect on the errors in foot placement that are often present among individuals who have experienced a stroke. |
Measure Participants | 14 | 17 | 13 |
4-week assessment |
-0.02
(0.22)
|
0.12
(0.20)
|
-0.04
(0.14)
|
8-week assessment |
0.05
(0.15)
|
0.11
(0.20)
|
-0.02
(0.16)
|
12-week assessment |
0
(0.08)
|
0.08
(0.18)
|
0.01
(0.12)
|
Follow-up assessment (after 12 weeks) |
-0.01
(0.16)
|
0.11
(0.18)
|
0
(0.14)
|
Statistical Analysis 1
Statistical Analysis Overview | Comparison Group Selection | Error Reduction, Error Augmentation, Activity Matched Control |
---|---|---|
Comments | ||
Type of Statistical Test | Superiority | |
Comments | ||
Statistical Test of Hypothesis | p-Value | 0.047 |
Comments | A priori threshold: 0.05 | |
Method | ANOVA | |
Comments | 0.047 is the main effect of group from a 2-way ANOVA that also included time (p=0.77) as a within-subjects factor. |
Title | Functional Gait Assessment (Change From Baseline) |
---|---|
Description | A commonly-used clinical test to quantify balance and stability during various walking tasks. The minimum value is 0, the maximum value is 30, and higher scores indicate better outcomes. The total maximum value of 30 is calculated as the sum of 10 subscores, each of which has a scoring range of 0-3 and represents a distinct walking task. The change in this measure relative to baseline is calculated at four time points (after 4, 8, 12, and 24 weeks). |
Time Frame | baseline, 4-weeks, 8-weeks, 12-weeks, 24-weeks |
Outcome Measure Data
Analysis Population Description |
---|
The total of 44 participants analyzed corresponds to the participants who completed the intervention and follow-up assessment. |
Arm/Group Title | Error Reduction | Error Augmentation | Activity Matched Control |
---|---|---|---|
Arm/Group Description | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error reduction" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error reduction: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs toward mechanically-appropriate mediolateral locations, having the effect of reducing the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error augmentation" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error augmentation: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs away from mechanically-appropriate mediolateral locations, having the effect of amplifying the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "transparent" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Activity matched control: During training sessions, participants will interface with a custom-built force-field while they walk. The force-field will essentially get out of the way, producing minimal forces on the legs, and having no direct effect on the errors in foot placement that are often present among individuals who have experienced a stroke. |
Measure Participants | 14 | 17 | 13 |
4-week assessment |
0.1
(1.8)
|
1.5
(2.3)
|
1.6
(2.1)
|
8-week assessment |
0.8
(2.3)
|
1.9
(2.7)
|
2.5
(2.8)
|
12-week assessment |
1.5
(2.5)
|
2.9
(1.9)
|
2.1
(1.8)
|
Follow-up assessment (after 12 weeks) |
1.0
(2.5)
|
2.2
(2.5)
|
1.9
(3.5)
|
Statistical Analysis 1
Statistical Analysis Overview | Comparison Group Selection | Error Reduction, Error Augmentation, Activity Matched Control |
---|---|---|
Comments | ||
Type of Statistical Test | Superiority | |
Comments | ||
Statistical Test of Hypothesis | p-Value | 0.16 |
Comments | A priori threshold: 0.05 | |
Method | ANOVA | |
Comments | 0.16 is the main effect of group from a 2-way ANOVA that also included time (p=0.023) as a within-subjects factor. |
Title | Activities-specific Balance Confidence Scale (Change From Baseline) |
---|---|
Description | A commonly-used clinical scale that quantifies an individual's confidence in performing various tasks requiring balance. The minimum value is 0, the maximum value is 100, and higher scores indicate a better outcome. The overall score is calculated as the mean of 16 subscores, each of which can range of 0 to 100 and represents self-efficacy at a distinct movement task. The change in this measure relative to baseline is calculated at four time points (after 4, 8, 12, and 24 weeks). |
Time Frame | baseline, 4-weeks, 8-weeks, 12-weeks, 24-weeks |
Outcome Measure Data
Analysis Population Description |
---|
The total of 44 participants analyzed corresponds to the participants who completed the intervention and follow-up assessment. |
Arm/Group Title | Error Reduction | Error Augmentation | Activity Matched Control |
---|---|---|---|
Arm/Group Description | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error reduction" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error reduction: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs toward mechanically-appropriate mediolateral locations, having the effect of reducing the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error augmentation" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error augmentation: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs away from mechanically-appropriate mediolateral locations, having the effect of amplifying the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "transparent" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Activity matched control: During training sessions, participants will interface with a custom-built force-field while they walk. The force-field will essentially get out of the way, producing minimal forces on the legs, and having no direct effect on the errors in foot placement that are often present among individuals who have experienced a stroke. |
Measure Participants | 14 | 17 | 13 |
4-week assessment |
2.2
(11.2)
|
-0.6
(6.9)
|
3.7
(10.3)
|
8-week assessment |
2.5
(12.9)
|
-1.2
(4.9)
|
4.1
(16.2)
|
12-week assessment |
6.1
(16.4)
|
2.8
(6.8)
|
5.4
(12.5)
|
Follow-up assessment (after 12 weeks) |
8.1
(14.7)
|
4.6
(7.9)
|
3.7
(22.8)
|
Statistical Analysis 1
Statistical Analysis Overview | Comparison Group Selection | Error Reduction, Error Augmentation, Activity Matched Control |
---|---|---|
Comments | ||
Type of Statistical Test | Superiority | |
Comments | ||
Statistical Test of Hypothesis | p-Value | 0.64 |
Comments | A priori threshold: 0.05 | |
Method | ANOVA | |
Comments | 0.64 is the main effect of group from a 2-way ANOVA that also included time (p=0.024) as a within-subjects factor. |
Title | 10-meter Walk Test (Change From Baseline) |
---|---|
Description | A commonly-used clinical test to quantify general gait function. Walking speed is measured during the middle 6-meter portion of a 10-meter straight line path. The change in this measure relative to baseline is calculated at four time points (after 4, 8, 12, and 24 weeks). |
Time Frame | baseline, 4-weeks, 8-weeks, 12-weeks, 24-weeks |
Outcome Measure Data
Analysis Population Description |
---|
The total of 44 participants analyzed corresponds to the participants who completed the intervention and follow-up assessment. |
Arm/Group Title | Error Reduction | Error Augmentation | Activity Matched Control |
---|---|---|---|
Arm/Group Description | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error reduction" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error reduction: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs toward mechanically-appropriate mediolateral locations, having the effect of reducing the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error augmentation" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error augmentation: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs away from mechanically-appropriate mediolateral locations, having the effect of amplifying the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "transparent" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Activity matched control: During training sessions, participants will interface with a custom-built force-field while they walk. The force-field will essentially get out of the way, producing minimal forces on the legs, and having no direct effect on the errors in foot placement that are often present among individuals who have experienced a stroke. |
Measure Participants | 14 | 17 | 13 |
4-week assessment |
0.01
(0.08)
|
0.03
(0.08)
|
0.03
(0.08)
|
8-week assessment |
0.02
(0.10)
|
0.04
(0.07)
|
0.04
(0.10)
|
12-week assessment |
0.05
(0.14)
|
0.02
(0.08)
|
0.06
(0.10)
|
Follow-up assessment (after 12 weeks |
0.01
(0.15)
|
0.01
(0.11)
|
0.01
(0.11)
|
Statistical Analysis 1
Statistical Analysis Overview | Comparison Group Selection | Error Reduction, Error Augmentation, Activity Matched Control |
---|---|---|
Comments | ||
Type of Statistical Test | Superiority | |
Comments | ||
Statistical Test of Hypothesis | p-Value | 0.92 |
Comments | A priori threshold: 0.92 | |
Method | ANOVA | |
Comments | 0.92 is the main effect of group from a 2-way ANOVA that also included time (p=0.076) as a within-subjects factor. |
Title | Fall Incidence |
---|---|
Description | Self-report history of fall occurrence, quantified by the average number of falls per participant in each group during the 12-week period that followed completion of the study's intervention component |
Time Frame | 6 months (during 12 week follow-up period) |
Outcome Measure Data
Analysis Population Description |
---|
The total of 44 participants analyzed corresponds to the participants who completed the intervention and follow-up assessment. |
Arm/Group Title | Error Reduction | Error Augmentation | Activity Matched Control |
---|---|---|---|
Arm/Group Description | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error reduction" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error reduction: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs toward mechanically-appropriate mediolateral locations, having the effect of reducing the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error augmentation" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error augmentation: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs away from mechanically-appropriate mediolateral locations, having the effect of amplifying the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "transparent" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Activity matched control: During training sessions, participants will interface with a custom-built force-field while they walk. The force-field will essentially get out of the way, producing minimal forces on the legs, and having no direct effect on the errors in foot placement that are often present among individuals who have experienced a stroke. |
Measure Participants | 14 | 17 | 13 |
Mean (Standard Error) [Falls per participant] |
0.50
(0.20)
|
0.29
(0.14)
|
0.62
(0.23)
|
Statistical Analysis 1
Statistical Analysis Overview | Comparison Group Selection | Error Reduction, Error Augmentation, Activity Matched Control |
---|---|---|
Comments | ||
Type of Statistical Test | Superiority | |
Comments | ||
Statistical Test of Hypothesis | p-Value | >=0.22 |
Comments | A priori threshold: 0.05 | |
Method | Mixed Models Analysis | |
Comments | We compared incident rates assuming a negative binomial distribution with leas squares means estimates predicted via generalized linear model. |
Title | Fear of Falling |
---|---|
Description | Self-report statement of whether a participant has a fear of falling |
Time Frame | 6 months (at completion of 12-week Follow-up period) |
Outcome Measure Data
Analysis Population Description |
---|
The total of 44 participants analyzed corresponds to the participants who completed the intervention and follow-up assessment. |
Arm/Group Title | Error Reduction | Error Augmentation | Activity Matched Control |
---|---|---|---|
Arm/Group Description | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error reduction" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error reduction: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs toward mechanically-appropriate mediolateral locations, having the effect of reducing the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error augmentation" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error augmentation: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs away from mechanically-appropriate mediolateral locations, having the effect of amplifying the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "transparent" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Activity matched control: During training sessions, participants will interface with a custom-built force-field while they walk. The force-field will essentially get out of the way, producing minimal forces on the legs, and having no direct effect on the errors in foot placement that are often present among individuals who have experienced a stroke. |
Measure Participants | 14 | 17 | 13 |
Count of Participants [Participants] |
4
22.2%
|
5
27.8%
|
4
22.2%
|
Statistical Analysis 1
Statistical Analysis Overview | Comparison Group Selection | Error Reduction, Error Augmentation, Activity Matched Control |
---|---|---|
Comments | ||
Type of Statistical Test | Superiority | |
Comments | ||
Statistical Test of Hypothesis | p-Value | 0.99 |
Comments | A priori threshold: 0.05 | |
Method | Chi-squared | |
Comments |
Adverse Events
Time Frame | Adverse event data were collected over a three-year period, corresponding from the time when the first participant was enrolled into the intervention to the time when the overall intervention ended. | |||||
---|---|---|---|---|---|---|
Adverse Event Reporting Description | We adhered to guidance provided by the Medical University of South Carolina Institutional Review Board; in order for an event to be classified as a reportable adverse event, it cannot be "the expected natural progression of any underlying disease, disorder, or condition of the subject experiencing the adverse event and the subject's predisposing risk factor profile for the adverse event". While we tracked falls, they are thus not included as adverse events. | |||||
Arm/Group Title | Error Reduction | Error Augmentation | Activity Matched Control | |||
Arm/Group Description | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error reduction" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error reduction: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs toward mechanically-appropriate mediolateral locations, having the effect of reducing the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "error augmentation" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Error augmentation: During training sessions, a custom-built force-field will exert forces on the legs while participants walk. These forces will push the legs away from mechanically-appropriate mediolateral locations, having the effect of amplifying the errors in foot placement that are often present among individuals who have experienced a stroke. | Participants will complete a 12-week training program, in which they practice walking on a treadmill for 30-minutes during twice-weekly training sessions. During these sessions, participants will interface with a custom-built force-field able to exert mediolateral forces on the legs, which will be in "transparent" mode. This training period will be followed by a 12-week follow-up period. Five assessment sessions will be interspersed throughout this total 24-week period. Activity matched control: During training sessions, participants will interface with a custom-built force-field while they walk. The force-field will essentially get out of the way, producing minimal forces on the legs, and having no direct effect on the errors in foot placement that are often present among individuals who have experienced a stroke. | |||
All Cause Mortality |
||||||
Error Reduction | Error Augmentation | Activity Matched Control | ||||
Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | |
Total | 0/18 (0%) | 0/18 (0%) | 0/18 (0%) | |||
Serious Adverse Events |
||||||
Error Reduction | Error Augmentation | Activity Matched Control | ||||
Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | |
Total | 0/18 (0%) | 0/18 (0%) | 1/18 (5.6%) | |||
Vascular disorders | ||||||
Stroke | 0/18 (0%) | 0 | 0/18 (0%) | 0 | 1/18 (5.6%) | 1 |
Other (Not Including Serious) Adverse Events |
||||||
Error Reduction | Error Augmentation | Activity Matched Control | ||||
Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | |
Total | 0/18 (0%) | 0/18 (0%) | 0/18 (0%) |
Limitations/Caveats
More Information
Certain Agreements
All Principal Investigators ARE employed by the organization sponsoring the study.
There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.
Results Point of Contact
Name/Title | Jesse Dean |
---|---|
Organization | Ralph H. Johnson VAMC / MUSC |
Phone | 8437929566 |
deaje@musc.edu |
- N2256-R
- RX002256