Perturbation-induced Reactive Standing BalanceTraining in Persons Post Stroke
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Northwestern University
- Enrollment
- 13
- Locations
- 2
- Primary Endpoint
- Change in frequency of stepping with paretic leg after a perturbation
Study Overview
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.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 21 Years to 80 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •at least 1 year post a single unilateral hemispheric stroke (CVA)
- •living independently in the community
- •able to walk 25 feet without assistive device
Exclusion Criteria
- •pain that limits movement
- •joint surgery of the lower extremity
- •unable to give consent
- •significant postural alignment deficits such as scoliosis or genu recurvatum
- •loss of sensation in the lower limb
Outcomes
Primary Outcomes
Change in frequency of stepping with paretic leg after a perturbation
Time Frame: Change in stepping with paretic leg will be modeled from baseline and immediately after the intervention.
number of trials when the paretic leg takes the first reactive step after the perturbation is applied during the reactive trials.
Change in step onset time for voluntary and reactive steps
Time Frame: Change in step onset will be modeled from baseline and immediately after the intervention.
step onset time is the time the stepping foot lifts off the ground after the Go cue for voluntary steps and after the perturbation for the reactive steps.
Change in reactive lean balance test
Time Frame: Change in reactive lean balance test will be modeled from baseline and immediately after the intervention.
Lean balance test is a passive way to test reactive stepping. Participants will lean again the research staff hands until their center of mass is at the edge of their feet. The research staff will suddenly remove their hands and allow the participant to catch their balance. Research staff are trained to perform the test and to guard the participant if needed. Extra personnel will be near by for additional support if the participant is not able to recover their balance.
Secondary Outcomes
- 10 meter walk test(Day 1 before training)
- Activities-specific Balance Confidence scale (ABC)(Day 1 before training)
Investigators
Katherine Martinez
Assistant Professor
Northwestern University