Assessment of a Hybrid Pump for Vacuum Suspension of Prosthetic Sockets for Persons With Lower Limb Loss to Characterize the Effects of Added Movement on Socket-reaction Torques (HIPPI)

Hybrid Electrical-Mechanical Pump for Vacuum Suspension of Prosthetic Sockets

Prostheses can be suspended from the amputated limb using a variety of techniques, such as straps and suction. Suspending the prosthesis by creating a vacuum between the prosthetic socket and limb using a pump has benefits over other techniques including improved limb health and mobility. A new pump design will be tested by prosthesis users in the laboratory to verify its functionality during walking.

Study Overview

• Status: Completed
• Conditions: Amputation
• Intervention / Treatment: Other: Pump prototype

Detailed Description

Human subject testing will involve a cross-sectional, repeated measures study consisting of a single 3 hour visit wherein participants will initially stand and then continuously walk at their self-selected speed for ten minutes on a level treadmill with the prototype under two randomly presented conditions of the mechanical system: 1) fully functional, and 2) locked to restrict axial displacement. After written informed consent is obtained, information on socket comfort and mobility capability will be collected. A load-cell will be installed proximal to the prototype and in-line with the prosthesis to measure instantaneous socket-reaction moments.

• Study Type: Interventional
• Enrollment (Actual): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Illinois
    • Chicago, Illinois, United States, 60612
      • Jesse Brown VA Medical Center, Chicago, IL

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Ability to stand quietly and walk for 10 minutes continuously without an assistive device (e.g. cane or walker) and without undue fatigue or health risks
• Pre-classified clinically to be at least a limited community ambulator of Medicare Functional Classification Level (K)2
• Residual limb in good health
• At least six months experience with a definitive prosthesis that utilizes vacuum assisted suspension

Exclusion Criteria:

• Pathologies aside from amputation or taking medicine that would influence walking or balance
• Poor prosthetic fit or poor residual limb sensation

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Locked; The prototype mechanical system is locked from compressing	Other: Pump prototype; Effects of pump function on gait
Experimental: Unlocked; The prototype mechanical system is free to compress normally	Other: Pump prototype; Effects of pump function on gait

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Socket-reaction moments	Maximum moment (torques) generated at the prosthetic socket end during walking	Immediate

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Socket Comfort	Comfort of the prosthetic socket	Immediate
Perceived mobility capability	Mobility capability as reported by the participant	Immediate

Collaborators and Investigators

• Sponsor: VA Office of Research and Development
• Investigators: Principal Investigator: Matthew J. Major, PhD, Jesse Brown VA Medical Center, Chicago, IL

Study record dates

Study Major Dates

• Study Start (Actual): April 4, 2020
• Primary Completion (Actual): March 31, 2026
• Study Completion (Actual): March 31, 2026

Study Registration Dates

• First Submitted: November 15, 2019
• First Submitted That Met QC Criteria: January 14, 2020
• First Posted (Actual): January 18, 2020

Study Record Updates

• Last Update Posted (Actual): May 11, 2026
• Last Update Submitted That Met QC Criteria: May 6, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Gait; Prosthesis; Amputation; Leg
• Other Study ID Numbers: A3090-R; RX003090-01A2 (Other Grant/Funding Number: Dept Veterans Affairs)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No