Exoskeleton for Balance

Official title

Improving Mediolateral Walking Balance With an Assistive Exoskeleton

Overview

Many people who have experienced a stroke have deficits in their walking balance. The long-term goal of this research is to develop an exoskeleton that can effectively improve walking balance, thus improving functional mobility.

Detailed description

Walking balance is an important component of functional mobility, with post-stroke balance deficits contributing to a fall rate more than double that of age-matched controls. Unfortunately, traditional therapy approaches have not succeeded in addressing balance deficits or reducing fall risk, motivating the use of technology to fill this gap. Although assistive exoskeletons are a promising approach to improve post-stroke mobility, they have generally not been designed to control walking balance and agility. This limitation is a particular concern in the development of devices for people with stroke, as applying forces to "assist" some aspect of walking (including balance) can have unexpected negative effects. The project goal is to investigate the potential of exoskeleton assistance to improve walking balance that will be accepted by people with stroke. To this end, investigators will use a previously developed hip exoskeleton to quantify the effects of assisting gait stabilization.

Interventions

• Device No Exoskeleton
  The participant will not wear an exoskeleton
• Device Exoskeleton (zero impedance)
  The participant will wear an exoskeleton with zero impedance
• Device Exoskeleton (low impedance)
  The participant will wear an exoskeleton with low joint impedance
• Device Exoskeleton (medium impedance)
  The participant will wear an exoskeleton with medium joint impedance
• Device Exoskeleton (high impedance)
  The participant will wear an exoskeleton with high impedance

Primary outcome measures

• Partial correlation (rSW) between mediolateral pelvis displacement and step width during unperturbed walking [Time frame: Visit 2, anticipated average 1 week]
• Partial correlation (rSW) between mediolateral pelvis displacement and step width during speed perturbations [Time frame: Visit 4, anticipated average 1 year]
• Partial correlation (rSW) between mediolateral pelvis displacement and step width during vision perturbations [Time frame: Visit 4, anticipated average 1 year]
• Partial correlation (rSW) between mediolateral pelvis displacement and step width during mediolateral pull perturbations [Time frame: Visit 4, anticipated average 1 year]

Secondary outcome measures (12)

• Partial correlation between mediolateral pelvis displacement and mediolateral foot placement (unperturbed walking) [Time frame: Visit 2, anticipated average 1 week]
• Average gluteus medius activity during stance phase (surface EMG) in unperturbed walking [Time frame: Visit 2, anticipated average 1 week]
• Average gluteus medius activity during swing phase (surface EMG) in unperturbed walking [Time frame: Visit 2, anticipated average 1 week]
• Rating of Perceived Stability (RPS) during unperturbed walking [Time frame: Visit 2, anticipated average 1 week]
• Partial correlation between mediolateral pelvis displacement and mediolateral foot placement during speed perturbations [Time frame: Visit 4, anticipated average 1 year]
• Average gluteus medius activity during stance phase (surface EMG) with speed perturbations [Time frame: Visit 4, anticipated average 1 year]
• Average gluteus medius activity during swing phase (surface EMG) with speed perturbations [Time frame: Visit 4, anticipated average 1 year]
• Rating of Perceived Stability (RPS) with speed perturbations [Time frame: Visit 4, anticipated average 1 year]
• Partial correlation between mediolateral pelvis displacement and mediolateral foot placement during vision perturbations [Time frame: Visit 4, anticipated average 1 year]
• Average gluteus medius activity during stance phase (surface EMG) with vision perturbations [Time frame: Visit 4, anticipated average 1 year]
• Average gluteus medius activity during swing phase (surface EMG) with vision perturbations [Time frame: Visit 4, anticipated average 1 year]
• Rating of Perceived Stability (RPS) with vision perturbations [Time frame: Visit 4, anticipated average 1 year]

Eligibility criteria

Inclusion criteria

• Evidence of a stroke at least 6 months prior to participation
• Evidence of dysfunction of the paretic lower limb (Fugl-Meyer lower extremity motor score < 34)
• At least 21 years of age
• Self-reported experience of a fall in the previous year, and/or a fear of falling
• Gait speed of at least 0.2 m/s
• Ability to walk on a treadmill without a cane or walker
• Ability to follow three step commands and communicate with experimenters to answer questions (e.g., regarding their balance confidence)
• Provision of informed consent

Exclusion criteria

• Resting blood pressure higher than 220/110 mm Hg
• History of unstable cardiac arrhythmias, hypertrophic cardiomyopathy, severe aortic stenosis, angina or dyspnea at rest or during activities of daily living
• Preexisting neurological orders or dementia
• Legal blindness or severe visual impairment
• Presence of neglect
• History of DVT 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

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

N/A

Model

Single group

Masking

Open label

Primary purpose

Basic science

Study locations

United States · 1 center

• Medical University of South Carolina — Charleston

Identifiers

NCT: NCT07356011 · Pro00135871 · REGE22000170

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗