Clinical trial NCT04338815: Exoskeleton Variability Optimization
Official title: Exoskeleton Variability Optimization for Reducing Gait Variability for Patients With Peripheral Artery Disease
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Peripheral Arterial Disease
Keywords: Exoskeleton
Lead sponsor: University of Nebraska
Sponsor class: OTHER
First posted: 2020-04-08
Enrollment: 22
Sex: ALL
Minimum age (years): 19
Maximum age (years): 85
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: The investigators will evaluate a potentially faster and more clinically feasible method to optimize exoskeletons in pilot tests in healthy in preparation for patients with peripheral artery disease.

Detailed description: This study will test different methods for optimizing exoskeletons. It will consist of an habituation session to the hip exoskeleton, an optimization session to find the optimal actuation settings using an algorithm that converges toward the optimum based on real-time measurements (human-inthe-loop algorithm) and a post-test at the end of optimization session to compare different conditions. The outcomes will be evaluated by surface electromyography (Delsys), exoskeleton sensors (Futek), ground reaction force (Bertec treadmill), walking speed (Bertec treadmill), indirect calorimetry (Cosmed), and motion capture (Vicon).

Eligibility criteria: Inclusion Criteria:

* Ability to provide written consent
* Chronic claudication history
* Ankle-brachial index \< 0.90 at rest
* Stable blood pressure, lipides, and diabetes for \> 6 weeks
* Ability to walk on a treadmill for multiple five-minute spans.
* Ability to fit in exoskeleton: waist circumference 78 to 92 centimeters, thigh circumference 48 to 60 centimeters, minimal thigh length 28 centimeters.

Exclusion Criteria:

* Rest pain or tissue loss due to peripheral artery disease (Fontaine stage III and IV).
* Foot ulceration.
* Acute lower extremity event secondary to thromboembolic disease or acute trauma
* Walking capacity limited by diseases which are unrelated to peripheral artery disease such as:

Neurological disorders, musculoskeletal disorders (arthritis, scoliosis, stroke, spinal injury, etc.), a history of ankle instability, knee injury, diagnosed joint laxity, lower limb injury, surgery within the past 12 months, joint replacement, pulmonary disease or breathing disorders, cardiovascular disease, or vestibular disorder. This will be determined by verbal questioning from research personnel by verbally asking about conditions limiting their walking, whether subjects are taking medications for those conditions, and physicians' recommendations about limiting activity.

* Acute injury or pain in their lower extremity or current illness.
* Inability to follow visual cues due to blindness.
* Inability to follow auditory cues due to deafness.
* Women who are currently pregnant are excluded for safety reasons.

Primary outcomes:
measure: Time to convergence
timeFrame: 10 minutes
measure: Peak extension timing
timeFrame: 20 seconds
measure: Peak flexion timing
timeFrame: 20 seconds
measure: Largest lyapunov exponent
timeFrame: 20 seconds
Secondary outcomes:
Other outcomes:
Locations:
city: Omaha
country: United States
facility: University of Nebraska Omaha
state: Nebraska
Study officials:
affiliation: University of Nebraska
name: Philippe Malcolm
role: PRINCIPAL_INVESTIGATOR
References: