Effects of Remote Ischemic Conditioning on Hand Use in Individuals With SCI and ALS

Summary

Rehabilitation interventions such as physical training and neural stimulation after spinal cord injury (SCI) have been shown to increase neural plasticity. However, both physical training and neural stimulation require a large number of repetitions, and the retention of the intervention effects may be fleeting. In this proposal the investigators will test Remote ischemic conditioning (RIC), which has been shown to promote neural plasticity and has practical and theoretical advantages. RIC consists of transiently restricting blood flow to any 'remote' limb using a blood pressure cuff. This induces several of the body's systemic defensive reactions. RIC has been shown to improve motor learning. The investigators propose that RIC alters motor pathway excitability through a combination of systemic increases in plasticity-promoting factors and inhibition of inflammatory factors. The investigators have designed a clinical trial to test this hypothesis in 8 persons with SCI and 8 able-bodied controls. All participants will receive active/sham RIC plus a hand exercise. The investigators will measure effects on blood pressure, motor neuron excitability, and systemic inflammatory markers before and after RIC as well as after hand exercise. Starting July 2021, we will also enroll 5 individuals with Amyotrophic lateral sclerosis (ALS) in this study.

Conditions

• Spinal Cord Injuries
• Amyotrophic Lateral Sclerosis

Interventions

OTHER

Active Remote Ischemic Conditioning

The active RIC protocol involves 5 cycles of 5-min inflation and 5-min deflation on the non-target arm. The active RIC will be achieved via blood pressure cuff inflation to 200 mmHg.

OTHER

Sham Remote Ischemic Conditioning

The sham RIC protocol involves 5 cycles of 5-min inflation and 5-min deflation on the non-target arm. The sham RIC will be achieved via blood pressure cuff inflation to 10 mmHg below the subjects' diastolic blood pressure which would not cause the blood occlusion.

OTHER

Isometric hand exercise

Participants will be instructed to pinch a dynamometer with thumb and index finger at different intensities and durations. The intensities of pinch force will be 10%, 25%, and 50% of the maximal voluntary contraction (MVC). For each intensity, durations of 2, 4, and 6 s will be employed, which resulted in nine different combinations delivered in pseudorandom order. Participants will perform 2 sets of the isometric hand exercise (18 pinches in total). The interval between each pinch will be 2 seconds, with 30 second intervals between each set.

Sponsors & Collaborators

• Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

  collaborator NIH

• Bronx VA Medical Center

  lead FED

Principal Investigators

• Yu-Kuang Wu, PT, PhD · James J. Peters VA Medical Center

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

75 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2019-10-28

Primary Completion

2022-07-30

Completion

2022-10-31

Countries

• United States

Study Locations