Plantarflexor PAS - Stroke

NCT04515407 | Completed

• 2 other identifiers: B3609-P1I21RX003609-01
• Study Type: interventional
• Target: 10
• Locations: 1 country
• Sites: 1

Brief Summary

The current project investigates a method called paired associative stimulation (PAS) which is known to influence nervous system function through a process called neuroplasticity. Here the investigators will target function of the ankle plantarflexor muscles because they are critically important to walking. The investigators will study adults who have walking dysfunction resulting from stroke. The study will test three ways of delivering PAS targeted towards brain-muscle connections serving the ankle plantarflexors. The overall goal is to improve functioning of the plantarflexors. The investigators believe that improving plantarflexor function will increase the likelihood of positive effects from gait retraining programs for people post-stroke. Participants will experience all three PAS methods in separate sessions. The investigators will compare differences in the size of these effects to identify the optimal method for delivery of PAS to the ankle plantarflexors. This study is a preliminary step to help us design a better clinical trial of combined PAS and gait retraining.

Conditions

Stroke; Hemiparesis; Gait Dysfunction

Keywords

stroke, adult, gait, neuroplasticity

Outcome Measures

Primary Outcomes (2)

• change in Motor Evoked Potential (MEP) size

  The difference in MEP size (area) post-PAS compared to pre-PAS will be quantified as the primary outcome for Aim 1. MEP size is considered an indicator of cortical/neural excitability. An increase in MEP size would suggest that PAS enhanced cortical excitability. MEP size can be expressed in either absolute/raw values or percentage change relative to baseline. A single session of PAS lasts 30-45 minutes.

  immediately post-PAS

• change in ankle plantarflexor power (A2)

  The difference in A2 post-PAS compared to pre-PAS will be quantified as the primary outcome for Aim 2. A2 quantifies the dynamic force producing capacity and is critical to forward progression during walking. An increase in A2 amplitude, area, or slope would suggest that PAS enhanced cortical excitability/neural connectivity enabling production of greater, more effective plantarflexor power during walking. A2 is expressed relative to the individual subject's body weight. Change in A2 can be expressed in either these normalized units or percentage change relative to baseline. A single session of PAS lasts 30-45 minutes.

  immediately post-PAS

Study Arms (3)

Order 1

OTHER

All participants will receive PAS in three experimental conditions, randomized to the order of condition. Experimental order will be counterbalanced across participants. Order 1 will be: Seated@Rest, Seated@Active, Walking.

Other: PAS at Rest; Other: PAS - Active; Other: PAS - Walking

Order 2

OTHER

All participants will receive PAS in three experimental conditions, randomized to the order of condition. Experimental order will be counterbalanced across participants. Order 2 will be: Seated@Active, Walking, Seated@Rest.

Other: PAS at Rest; Other: PAS - Active; Other: PAS - Walking

Order 3

OTHER

All participants will receive PAS in three experimental conditions, randomized to the order of condition. Experimental order will be counterbalanced across participants. Order 3 will be: Walking, Seated@Rest, Seated@Active.

Other: PAS at Rest; Other: PAS - Active; Other: PAS - Walking

Interventions

PAS at Rest OTHER

Paired Associative Stimulation will be delivered while the participant is seated and resting.

Also known as: REST

Order 1; Order 2; Order 3

PAS - Active OTHER

Paired Associative Stimulation will be delivered while the participant is seated and producing submaximal background activity in the plantarflexor muscles.

Also known as: Active

Order 1; Order 2; Order 3

PAS - Walking OTHER

Paired Associative Stimulation will be delivered while the participant is walking, during the late stance phase of the gait cycle.

Also known as: Walking

Order 1; Order 2; Order 3

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• hemiparesis resulting from stroke
• single, unilateral, hemispheric stroke (cortical or sub-cortical areas)
• stroke confirmed by neuroimaging (CT or MRI)
• stroke 3 months prior to enrollment
• ability to walk, independently at least 25' on level ground, even if requiring brace or assistive device (cane)
• Veteran Status prioritized

You may not qualify if:

• lower extremity pain affecting ability to bear weight on legs
• contractures limiting normal range of motion in major lower extremity joints
• other neurological conditions (e.g., Parkinson's Disease, Multiple Sclerosis, ALS), prior traumatic brain injury, severe osteoarthritis or prior pathological fracture
• cardiovascular conditions contraindicative to walking or light exercise
• severe hypertension (i.e., \>200/110 at rest that cannot be controlled in resting range of 180/110 mmHg)
• perceptual or cognitive deficits affecting ability to: comprehend, follow three step directions, or provide consent

Sponsors & Collaborators

• VA Office of Research and Development: lead

Study Sites (1)

Martinez Outpatient Clinic and Community Living Center, Martinez, CA

Martinez, California, 94553, United States

Location

MeSH Terms

Conditions

Stroke; Paresis

Interventions

Exercise; Walking

Condition Hierarchy (Ancestors)

Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena; Locomotion

Study Officials

• Carolynn Patten, PhD

  Martinez Outpatient Clinic and Community Living Center, Martinez, CA

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Masking Details: Participants will be informed only that three conditions are being delivered and tested. The outcomes assessor will be provided only session (e.g., 1, 2, 3) information without knowledge of the condition experienced in that session.
• Purpose: OTHER
• Intervention Model: SINGLE GROUP
• Sponsor Type: FED
• Responsible Party: SPONSOR

Model Details: All participants will receive PAS in all three experimental conditions. Each condition will be delivered in a separate session. Sessions will be separated by one week. The order of conditions will be counterbalanced across subjects.

Study Record Dates

• First Submitted: July 30, 2020
• First Posted: August 17, 2020
• Study Start: October 1, 2021
• Primary Completion: August 31, 2023
• Study Completion: September 30, 2023
• Last Updated: February 22, 2024

Record last verified: 2024-02

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)