AmputationHIPPINCT04230512
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
A study testing Pump prototype in people with Amputation, run by VA Office of Research and Development at 1 site in United States.
Trial summary
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. Read more about this study
- Who is it for?
- Ages 18 to 80 years
- Conditions the study is for
- Amputation
- What is being tested?
- Pump prototype
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 12 participants
- Where
- 1 siteUnited States
- Study dates
- 4 Apr 2020to 31 Mar 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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
Who cannot join
- Pathologies aside from amputation or taking medicine that would influence walking or balance
- Poor prosthetic fit or poor residual limb sensation
Trial locations and contacts
1 site in 1 country.
United States1 site
Jesse Brown VA Medical Center, Chicago, IL
Chicago, Illinois, 60612
About this study
Official title: 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.
Read the 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.
- Conditions
- Amputation
- Being tested
- Pump prototype
- Keywords
- Amputation, Prosthesis, Gait, Leg
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Pump prototypeOther
Effects of pump function on gait
| Study group | Role | What they receive |
|---|---|---|
| Locked | Experimental | The prototype mechanical system is locked from compressing Receives: Other: Pump prototype |
| Unlocked | Experimental | The prototype mechanical system is free to compress normally Receives: Other: Pump prototype |
What is being measured
The primary outcome is the main question the study is designed to answer.
Socket-reaction moments
Maximum moment (torques) generated at the prosthetic socket end during walking
Measured: Immediate
Secondary outcomes (2)
Socket Comfort
Comfort of the prosthetic socket
Measured: Immediate
Perceived mobility capability
Mobility capability as reported by the participant
Measured: Immediate
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Jan 2020
- Study start4 Apr 2020
- Primary completion31 Mar 2026
- Study completion31 Mar 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for AmputationStudies of the same condition, open and under way.
- More trials run by VA Office of Research and DevelopmentThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Randomly assigned conditions of pump function to characterize the effects of added movement on socket-reaction torques
- Masking
- None (open label)
- Enrolment
- 12 participants (actual)
Sponsor and investigators
- Lead sponsor
- VA Office of Research and Development
- Sponsor type
- US federal agency
- Responsible party
- Sponsor
- Investigators
- Matthew J. Major, PhD, Principal investigator, Jesse Brown VA Medical Center, Chicago, IL
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04230512
- Sponsor's protocol ID
- A3090-R
- Other IDs
- RX003090-01A2
- Acronym
- HIPPI
- Status last verified
- May 2026
- First submitted
- 15 Nov 2019
- Last updated
- 11 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 11 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Hybrid Electrical-Mechanical Pump for Vacuum Suspension of Prosthetic Sockets
- ClinicalTrials.gov ID
- NCT04230512
- Acronym / sponsor ID
- HIPPI / A3090-R
- Conditions
- Amputation
- Keywords
- Amputation, Prosthesis, Gait, Leg
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 12 participants (actual)
- Lead sponsor
- VA Office of Research and DevelopmentUS federal agency
- Study start
- 4 Apr 2020 (actual)
- Primary completion
- 31 Mar 2026 (actual)
- Study completion
- 31 Mar 2026 (actual)
- First posted
- 18 Jan 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
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 design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Randomly assigned conditions of pump function to characterize the effects of added movement on socket-reaction torques
| Arm | Type | Receives |
|---|---|---|
| Locked | Experimental | Other: Pump prototypeThe prototype mechanical system is locked from compressing |
| Unlocked | Experimental | Other: Pump prototypeThe prototype mechanical system is free to compress normally |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- 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
Key exclusion criteria (2 listed)
- Pathologies aside from amputation or taking medicine that would influence walking or balance
- Poor prosthetic fit or poor residual limb sensation
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Pump prototypeEffects of pump function on gait | Other | Locked, Unlocked |
Primary outcome
Socket-reaction moments
Time frame: Immediate
Maximum moment (torques) generated at the prosthetic socket end during walking
2 secondary outcomes
Socket Comfort
Time frame: Immediate
Perceived mobility capability
Time frame: Immediate
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 11 May 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Matthew J. Major, PhD principal investigator
Jesse Brown VA Medical Center, Chicago, IL
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Pump prototype in people with Amputation, run by VA Office of Research and Development at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 11 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Socket-reaction moments (time frame: Immediate). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 May 2026.