Clinical trial NCT05772936: Reactive Standing Balance Step Training Post Stroke
Official title: Perturbation-induced Reactive Standing BalanceTraining in Persons Post Stroke
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Stroke, Cerebrovascular
Lead sponsor: Northwestern University
Sponsor class: OTHER
First posted: 2023-03-17
Enrollment: 13
Sex: ALL
Minimum age (years): 21
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to investigate the effectiveness of reactive step training on the timing and frequency of perturbation induced paretic leg stepping in persons post stroke. The study will consist of one or six one-hour training sessions and a pre and post visit each lasting up to two hours at our downtown Chicago location.

Detailed description: Perturbation induced step training. Perturbations will be applied by a mechanical weight drop system that has been used in previous studies. A belt with a cable will be attached to the subject's waist. The cable will be attached to metal weights that is held by an electromagnet on a vertical pole approximately 10-12ft from the subject. The weight will drop 52cm when the electromagnet is released. When the subject has attained and held a predetermined standing position for 1-3 seconds the mechanical perturbation will be activated. See training protocol below.

Pre and Post Testing Sessions: Subjects will be asked to complete pre and post testing sessions within 1 week of training. Testing sessions will include laboratory and clinical measures of balance and will last for approximately one hour.

Laboratory Measures: Participants will complete 2 standing trials, 12 voluntary stepping trials, and 12 anterior perturbation trials while standing on force platforms.

Standing trials: Subjects will be asked to stand feet hip with apart with each foot on a separate force plate that measure the pressure under their feet. Their foot placement will be traced so they can return to the same placement for each trial. Subjects will be instructed to cross their arms and stand as still as they can for 3 seconds, then march in place for 3 seconds.

Voluntary Stepping Trials: While standing with their feet in their foot tracings subjects will be asked to shift their weight until they assume a predetermined pressure under each foot. Visual feedback will be provided on a monitor in front of them. They will be instructed to hold that position until they see the "Go" cue on the screen at which point they should take 3 steps forward as fast as they can. There will be 6 stepping trials on each leg starting with the less involved leg.

Reactive Stepping Trials: Subjects will be secured in a safety harness that is mounted to the ceiling. The harness does not interfere with stepping but allows the person body weight to be supported if there is a loss of balance. A belt will be placed around the subjects' waist that will be connected by a cable to a mechanical weight drop device that will pull the subject forward to challenge their balance. The puller will provide mechanical perturbations up to 10% of subjects' body weight. The subjects will be instructed not resist the pull but to respond naturally and move their feet if needed to maintain up right posture. There will be ten reactive trials. Rest breaks will be given between voluntary and reactive trials or as needed.

Participants will complete 6 training sessions within a three-week period. Subjects will stand with their feet on a platform with a scale. Subjects will be instructed to try to use their more impaired leg if they need to step. The same mechanical perturbation that was used in the pre/post testing will be used for training with the belt attached to their waist. When they have attained and held a predetermined standing position for 1-3 seconds the mechanical perturbation will be activated. The weight bearing status of the more impaired leg will be increased by 5% after 10 out of 12 successive trials (i.e. stepping with the more impaired leg) or decreased by 5% if they always step with the less impaired leg after 6 trials. Training sessions will consist of 50 perturbation trials at 10% body weight and 3 catch trials at 2% body weight to discourage premature stepping. Training session will last about 1 hour. Subjects will be given rest breaks as needed.

Eligibility criteria: Inclusion Criteria:

1. at least 1 year post a single unilateral hemispheric stroke (CVA)
2. living independently in the community
3. able to walk 25 feet without assistive device

Exclusion Criteria:

1. pain that limits movement
2. joint surgery of the lower extremity
3. unable to give consent
4. significant postural alignment deficits such as scoliosis or genu recurvatum
5. loss of sensation in the lower limb

Primary outcomes:
measure: Change in frequency of stepping with paretic leg after a perturbation
timeFrame: Change in stepping with paretic leg will be modeled from baseline and immediately after the intervention.
measure: Change in step onset time for voluntary and reactive steps
timeFrame: Change in step onset will be modeled from baseline and immediately after the intervention.
measure: Change in reactive lean balance test
timeFrame: Change in reactive lean balance test will be modeled from baseline and immediately after the intervention.
Secondary outcomes:
measure: 10 meter walk test
timeFrame: Day 1 before training
measure: Activities-specific Balance Confidence scale (ABC)
timeFrame: Day 1 before training
Other outcomes:
Locations:
city: Chicago
country: United States
facility: Northwestern University
state: Illinois
Study officials:
affiliation: Northwestern University
name: Katherine M Martinez, PhD
role: PRINCIPAL_INVESTIGATOR
References: