Optimization of Hip-exoskeleton Weight Attributes

Not Applicable

Completed

• Conditions: Gait, Frontal; Healthy
• Interventions: Other: Weight belt

• Registration Number: NCT05120115
• Lead Sponsor: University of Texas at Austin

Brief Summary

The investigators are examining how weight distribution affects the way people walk, in terms of joint kinematics, kinetics, and muscle activity. The investigators are measuring these quantities while people walk while wearing a weighted belt. The investigators distribute the weights and walk for specified periods. They hypothesize that greater weight will have a greater effect on walking.

Detailed Description

The purpose of this study is to examine how the amount and distribution of weight on the pelvis affects how people walk. The investigators two factors, weight and placement. They are examining how these factors affect muscle activation, joint motions and foot forces. The investigators plan to recruit 40 healthy adult individuals. Each of the 20 experimental conditions (3x3 factorial and one control condition with no weight) will be recorded immediately in a single session. The investigators hypothesize that weight amount, gait speed and weight distribution will all affect how people walk, which will lead towards optimized design of hip exoskeletons.

Study Timeline

• Study First Submitted: 2021-06-11
• Study Start: 2021-10-07
• Study First Submitted QC: 2021-11-02
• Study First Posted: 2021-11-15
• Primary Completion: 2022-05-06
• Study Completion: 2022-05-06
• Results First Submitted: 2023-07-28
• Status Verified: 2023-11
• Results First Submitted QC: 2023-11-06
• Last Update Submitted: 2023-11-06
• Results First Posted: 2023-11-29
• Last Update Posted: 2023-11-29

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 21

Inclusion Criteria

• Willing to commit to the full experimental session

Exclusion Criteria

• Functionally relevant lower limb musculoskeletal injury

  • Functionally relevant osteoarthritis and weight bearing restrictions
  • Severe respiratory problems that restrict the wearer from using a metabolic rate apparatus

• Patients with cardiac issues may be included, but the cardiac issue will be noted in the health history questionnaire

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Weight distribution and placement	Weight belt	Changing where weight is distributed on belt around pelvis, specifically, bilaterally, 4th lumbar area, unilaterally on the left side. Also changing amount of weight at 0, 4, 6 and 8 kg.

Primary Outcome Measures

Name	Time	Method
Pelvic Obliquity	One day	Amount of pelvic obliquity in response to weighted belt measured using optical motion capture

Secondary Outcome Measures

Name	Time	Method
Knee Flexion Angle During Swing Phase	One Day	Knee flexion angle range of motion measured using optical motion capture
Integrated Gastrocnemius Muscle Activity During Preswing Phase of Walking	One day	EMG signals were normalized via the mean-dynamic method (Burden and Bartlett, 1999), centering the EMG signal around 1. For data analysis, the EMG signal was integrated along each gait phase to calculate the integrated EMG (iEMG) values. For the gastrocnemius, we extrated the iEMG during the pre-swing phase only. The iEMG was normalized to average during walking, resulting in arbitrary units.

Trial Locations

Locations (1)

University of Texas at Austin; 🇺🇸 Austin, Texas, United States