Lower Extremity AmputationNCT03532100
Pivot-Flex Foot: Optimal Coupling Ratio Between Transverse and Sagittal-plane Motions Using a Torsionally Adaptive Prosthesis for Individuals With Lower Limb Amputation
A study testing Torsionally adaptive prosthesis with 0:1 coupling ratio, Torsionally adaptive prosthesis with 1:6 coupling ratio and Torsionally adaptive prosthesis with 1:4 coupling ratio in people with Lower Extremity Amputation, run by VA Office of Research and Development at 1 site in United States.
Trial summary
When prescribing a prosthetic foot, clinicians face a dizzying array of choices as more than 200 different prosthetic feet are available. While these conventional prosthetic feet primarily function in the sagittal plane, the intact foot and ankle comprise a complex set of joints that allow rotation in multiple planes… Read more about this study
- Who is it for?
- Ages 18 to 70 years
- Conditions the study is for
- Lower Extremity Amputation
- What is being tested?
- Torsionally adaptive prosthesis with 0:1 coupling ratio, Torsionally adaptive prosthesis with 1:6 coupling ratio and Torsionally adaptive prosthesis with 1:4 coupling ratio
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 14 participants
- Where
- 1 siteUnited States
- Study dates
- 18 Apr 2018to 18 Nov 2024
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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 70 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Unilateral transtibial amputation
- Been fit with a prosthesis and used it for at least six months
- Wear the prosthesis for four or more hours on an average day
- Prescribed prosthesis can accommodate fitment of the study prosthetic components to be tested (determined at initial visit)
Who cannot join
- Improper fit and suspension with current prosthesis and one cannot be achieved with clinical resources (determined at initial visit)
- Current skin irritation or injury on residual limb
- Osteoarthritis, injury, or pain that interferes with walking ability
- Currently incarcerated
- Pregnant (determined via self-report)
- Inadequate cognitive function or language proficiency to consent to participate
Trial locations and contacts
1 site in 1 country.
United States1 site
VA Puget Sound Health Care System Seattle Division, Seattle, WA
Seattle, Washington, 98108-1532
About this study
Official title: Pivot-Flex Foot: Torsionally Adaptive Prosthesis for Individuals With Lower Limb Amputation
When prescribing a prosthetic foot, clinicians face a dizzying array of choices as more than 200 different prosthetic feet are available. While these conventional prosthetic feet primarily function in the sagittal plane, the intact foot and ankle comprise a complex set of joints that allow rotation in multiple planes of motion. Some of these motions are coupled, meaning rotation in one plane induces motion in another. One such coupling is between the sagittal and transverse planes. For every step, plantar- and dorsi-flexion motion in the sagittal plane is coupled with external and internal rotation of the shank relative to the foot in the transverse plane. There is no prosthetic foot available for prescription that mimics this natural coupling.
To investigate the need for this coupling, the investigators have built a torsionally adaptive prosthesis where the coupling ratio between the transverse- and sagittal-planes can be independently controlled with a motor.
Read more
This research has one specific aim: to identify the optimal coupling ratio between transverse- and sagittal-plane motions using a novel, torsionally adaptive prosthesis for individuals with lower limb amputation. The investigators will conduct a human subject experiment wearing the motor-driven and computer controlled torsionally adaptive prosthesis. Individuals with lower limb amputation will be asked to walk in a straight line and in both directions around a circle while the coupling ratio between transverse- and sagittal-plane motions is varied between trials. Participants will be blinded to the coupling ratio.
The investigators hypothesize that: (1) a coupling ratio exists that minimizes undesirable transverse-plane socket torque and (2) there will be a coupling ratio that individuals with lower limb amputation prefer.
Read the detailed description
The human ankle is a complex mechanism that does not behave like a simple hinge. Instead, rotations in all three axes are allowed and some are coupled together. In particular, the axis of rotation of the talo-crural joint during ankle flexion is inclined downwards and laterally relative to horizontal, and the rotation ranges from 10 to 26 degrees among individuals. This rotation couples plantar- and dorsi-flexion motion with external and internal rotation of the shank relative to the foot, respectively. This feature of the natural limb has not been replicated in prosthetic feet and ankles.
Lower limb amputees take thousands of steps on their prosthesis each day and none feature coupled motion between the transverse- and sagittal-planes. The absence of this natural coupling may be related to the high incidence of residual limb soft tissue injuries, the need for compensatory gait, and overall dissatisfaction with their prostheses.
Transverse rotation adapters, consisting of simple torsional springs, are available for prescription. These devices can increase transverse-plane rotations and decrease transverse-plane torques, but their use is not widespread and if excessively compliant, may reduce gait stability. Cost, weight, prosthesis build height, and the inability for the user to adjust the stiffness may all play a role in their lack of adoption, but it may also be that the transverse-plane rotation is not coupled with the sagittal-plane. With these devices, motion only occurs in the transverse-plane when a transverse-plane torque is applied.
This research has one specific aim: to identify the optimal coupling ratio between transverse- and sagittal-plane motions using a novel, torsionally adaptive prosthesis for individuals with lower limb amputation. The investigators will fit a sample population of unilateral transtibial amputees with the motor-driven and computer controlled torsionally adaptive prosthesis.
Participants perform three activities: walking in a straight line (study visit 1) and in both directions around a circle (study visit 2). During each of these three activities, the torsionally adaptive prosthesis will be set to five different coupling ratios in random order. Participants will be blinded to the coupling ratio.
The general hypotheses for this study are: (H1) a coupling ratio exists between 0 (no coupling) to 1:2 (one degree of transverse-plane motion for every two degrees of sagittal-plane motion) that minimizes transverse-plane socket torque and (H2) an amputee preferred coupling ratio will exist within this range.
This research will discover how best to couple transverse- and sagittal-plane motion in the prostheses of lower limb amputees.
- Conditions
- Lower Extremity Amputation
- Being tested
- Torsionally adaptive prosthesis with 0:1 coupling ratio, Torsionally adaptive prosthesis with 1:6 coupling ratio, Torsionally adaptive prosthesis with 1:4 coupling ratio, Torsionally adaptive prosthesis with 1:3 coupling ratio, Torsionally adaptive prosthesis with 1:2 coupling ratio
- Keywords
- lower limb prosthesis, transtibial amputation, below knee amputation, biomechanics, gait
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Torsionally adaptive prosthesis with 0:1 coupling ratioDevice
The torsionally adaptive prosthesis can be programmed to couple the motion between the transverse- and sagittal-planes. A coupling ratio (transverse:sagittal) of 0:1 means there will be no coupling between the transverse- and sagittal-plane motion. That is, regardless of any motion in the sagittal plane, there will be zero motion in the transverse plane.
Torsionally adaptive prosthesis with 1:6 coupling ratioDevice
The torsionally adaptive prosthesis can be programmed to couple the motion between the transverse- and sagittal-planes. A coupling ratio (transverse:sagittal) of 1:6 means there will be one degree of motion in the transverse plane for every six degrees of motion in the sagittal plane.
Torsionally adaptive prosthesis with 1:4 coupling ratioDevice
The torsionally adaptive prosthesis can be programmed to couple the motion between the transverse- and sagittal-planes. A coupling ratio (transverse:sagittal) of 1:4 means there will be one degree of motion in the transverse plane for every four degrees of motion in the sagittal plane.
Torsionally adaptive prosthesis with 1:3 coupling ratioDevice
The torsionally adaptive prosthesis can be programmed to couple the motion between the transverse- and sagittal-planes. A coupling ratio (transverse:sagittal) of 1:3 means there will be one degree of motion in the transverse plane for every three degrees of motion in the sagittal plane.
Torsionally adaptive prosthesis with 1:2 coupling ratioDevice
The torsionally adaptive prosthesis can be programmed to couple the motion between the transverse- and sagittal-planes. A coupling ratio (transverse:sagittal) of 1:2 means there will be one degree of motion in the transverse plane for every two degrees of motion in the sagittal plane.
| Study group | Role | What they receive |
|---|---|---|
| Straight line walking | Experimental | All participants will walk in a straight line while wearing the study prosthesis. Receives: Device: Torsionally adaptive prosthesis with 0:1 coupling ratio; Device: Torsionally adaptive prosthesis with 1:6 coupling ratio; Device: Torsionally adaptive prosthesis with 1:4 coupling ratio; Device: Torsionally adaptive prosthesis with 1:3 coupling ratio; Device: Torsionally adaptive prosthesis with 1:2 coupling ratio |
| Circle walking with prosthesis inside | Experimental | All participants will walk around a 1-meter radius circle with their prosthesis on the inside of the circle. Receives: Device: Torsionally adaptive prosthesis with 0:1 coupling ratio; Device: Torsionally adaptive prosthesis with 1:6 coupling ratio; Device: Torsionally adaptive prosthesis with 1:4 coupling ratio; Device: Torsionally adaptive prosthesis with 1:3 coupling ratio; Device: Torsionally adaptive prosthesis with 1:2 coupling ratio |
| Circle walking with prosthesis outside | Experimental | All participants will walk around a 1-meter radius circle with their prosthesis on the outside of the circle. Receives: Device: Torsionally adaptive prosthesis with 0:1 coupling ratio; Device: Torsionally adaptive prosthesis with 1:6 coupling ratio; Device: Torsionally adaptive prosthesis with 1:4 coupling ratio; Device: Torsionally adaptive prosthesis with 1:3 coupling ratio; Device: Torsionally adaptive prosthesis with 1:2 coupling ratio |
What is being measured
The primary outcome is the main question the study is designed to answer.
Peak Transverse-plane Prosthetic Socket Torque Normalized to Body Mass
Peak transverse-plane prosthetic socket torque measured while walking normalized to body mass
Measured: During walking trials for each coupling ratio
Secondary outcomes (1)
Satisfaction With the Prosthesis
An 11-point Likert scale will be used to record the subject's perception of satisfaction with the prosthesis after completing the trials for each coupling ratio. Participants will be asked to rate their satisfaction with the prosthesis on a 0 - 10 scale. Zero represented the most uncomfortable socket fit the subject could imagine, and ten represented the most comfortable socket fit.
Measured: Immediately following walking trials for each coupling ratio
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 May 2018
- Study start18 Apr 2018
- Primary completion1 Oct 2024
- Study completion18 Nov 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Lower Extremity 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
- Treatment
- Allocation
- Randomised
- Intervention model
- Factorial
- Model description
- This within-subject, cross-over, factorial design study (3 arms x 5 intervention settings) aims to identify the optimal coupling ratio between transverse- and sagittal-plane motions using a torsionally adaptive prosthesis. The 3 arms including walking in a straight line (study visit 1) and walking in a circle with their lower limb prosthesis on the inside and outside of the circle (study visit 2). The order in which the participants walk around a circle with their prosthesis on the inside or the outside will be randomized. The study intervention, a torsionally adaptive prosthesis, can be set to 5 different settings (i.e., coupling ratios) including 0:0, 1:6, 1:4, 1:3, and 1:2 (transverse:sagittal). Within each arm, each participant will walk with the torsionally adaptive prosthesis set to the 5 different settings in random order. Participants will not be blinded to the arm but will be blinded to the intervention setting (coupling ratio).
- Masking
- None (open label)
- Enrolment
- 14 participants (actual)
Sponsor and investigators
- Lead sponsor
- VA Office of Research and Development
- Sponsor type
- US federal agency
- Responsible party
- Sponsor
- Investigators
- Glenn K Klute, PhD, Principal investigator, VA Puget Sound Health Care System Seattle Division, Seattle, WA
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03532100
- Sponsor's protocol ID
- A2456-R
- Other IDs
- RX002456 Part 1, I01RX002456-01A1
- Status last verified
- Nov 2025
- First submitted
- 9 May 2018
- Last updated
- 19 Nov 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: A de-identified, anonymized dataset in machine-readable format will be created and shared for all individual participant data (IPD) that underlie results in a publication. The investigators will follow 164.514(a) of the HIPAA Privacy Rule for de-identification of IPD.
Study at a glance
From the registry record, last updated by the sponsor on 19 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Pivot-Flex Foot: Torsionally Adaptive Prosthesis for Individuals With Lower Limb Amputation
- ClinicalTrials.gov ID
- NCT03532100
- Acronym / sponsor ID
- A2456-R
- Conditions
- Lower Extremity Amputation
- Keywords
- lower limb prosthesis, transtibial amputation, below knee amputation, biomechanics, gait
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 14 participants (actual)
- Lead sponsor
- VA Office of Research and DevelopmentUS federal agency
- Study start
- 18 Apr 2018 (actual)
- Primary completion
- 1 Oct 2024 (actual)
- Study completion
- 18 Nov 2024 (actual)
- First posted
- 22 May 2018 (actual)
- Results
- Posted 19 Nov 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
When prescribing a prosthetic foot, clinicians face a dizzying array of choices as more than 200 different prosthetic feet are available. While these conventional prosthetic feet primarily function in the sagittal plane, the intact foot and ankle comprise a complex set of joints that allow rotation in multiple planes of motion. Some of these motions are coupled, meaning rotation in one plane induces motion in another. One such coupling is between the sagittal and transverse planes. For every step, plantar- and dorsi-flexion motion in the sagittal plane is coupled with external and internal rotation of the shank relative to the foot in the transverse plane. There is no prosthetic foot available for prescription that mimics this natural coupling.
To investigate the need for this coupling, the investigators have built a torsionally adaptive prosthesis where the coupling ratio between the transverse- and sagittal-planes can be independently controlled with a motor.
This research has one specific aim: to identify the optimal coupling ratio between transverse- and sagittal-plane motions using a novel, torsionally adaptive prosthesis for individuals with lower limb amputation. The investigators will conduct a human subject experiment wearing the motor-driven and computer controlled torsionally adaptive prosthesis. Individuals with lower limb amputation will be asked to walk in a straight line and in both directions around a circle while the coupling ratio between transverse- and sagittal-plane motions is varied between trials. Participants will be blinded to the coupling ratio.
The investigators hypothesize that: (1) a coupling ratio exists that minimizes undesirable transverse-plane socket torque and (2) there will be a coupling ratio that individuals with lower limb amputation prefer.
Detailed description
The human ankle is a complex mechanism that does not behave like a simple hinge. Instead, rotations in all three axes are allowed and some are coupled together. In particular, the axis of rotation of the talo-crural joint during ankle flexion is inclined downwards and laterally relative to horizontal, and the rotation ranges from 10 to 26 degrees among individuals. This rotation couples plantar- and dorsi-flexion motion with external and internal rotation of the shank relative to the foot, respectively. This feature of the natural limb has not been replicated in prosthetic feet and ankles.
Lower limb amputees take thousands of steps on their prosthesis each day and none feature coupled motion between the transverse- and sagittal-planes. The absence of this natural coupling may be related to the high incidence of residual limb soft tissue injuries, the need for compensatory gait, and overall dissatisfaction with their prostheses.
Transverse rotation adapters, consisting of simple torsional springs, are available for prescription. These devices can increase transverse-plane rotations and decrease transverse-plane torques, but their use is not widespread and if excessively compliant, may reduce gait stability. Cost, weight, prosthesis build height, and the inability for the user to adjust the stiffness may all play a role in their lack of adoption, but it may also be that the transverse-plane rotation is not coupled with the sagittal-plane. With these devices, motion only occurs in the transverse-plane when a transverse-plane torque is applied.
This research has one specific aim: to identify the optimal coupling ratio between transverse- and sagittal-plane motions using a novel, torsionally adaptive prosthesis for individuals with lower limb amputation. The investigators will fit a sample population of unilateral transtibial amputees with the motor-driven and computer controlled torsionally adaptive prosthesis.
Participants perform three activities: walking in a straight line (study visit 1) and in both directions around a circle (study visit 2). During each of these three activities, the torsionally adaptive prosthesis will be set to five different coupling ratios in random order. Participants will be blinded to the coupling ratio.
The general hypotheses for this study are: (H1) a coupling ratio exists between 0 (no coupling) to 1:2 (one degree of transverse-plane motion for every two degrees of sagittal-plane motion) that minimizes transverse-plane socket torque and (H2) an amputee preferred coupling ratio will exist within this range.
This research will discover how best to couple transverse- and sagittal-plane motion in the prostheses of lower limb amputees.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Factorial
- Masking
- None (open label)
- Number of arms
- 3
- Model description
- This within-subject, cross-over, factorial design study (3 arms x 5 intervention settings) aims to identify the optimal coupling ratio between transverse- and sagittal-plane motions using a torsionally adaptive prosthesis. The 3 arms including walking in a straight line (study visit 1) and walking in a circle with their lower limb prosthesis on the inside and outside of the circle (study visit 2). The order in which the participants walk around a circle with their prosthesis on the inside or the outside will be randomized. The study intervention, a torsionally adaptive prosthesis, can be set to 5 different settings (i.e., coupling ratios) including 0:0, 1:6, 1:4, 1:3, and 1:2 (transverse:sagittal). Within each arm, each participant will walk with the torsionally adaptive prosthesis set to the 5 different settings in random order. Participants will not be blinded to the arm but will be blinded to the intervention setting (coupling ratio).
| Arm | Type | Receives |
|---|---|---|
| Straight line walking | Experimental | Device: Torsionally adaptive prosthesis with 0:1 coupling ratio, Device: Torsionally adaptive prosthesis with 1:6 coupling ratio, Device: Torsionally adaptive prosthesis with 1:4 coupling ratio, Device: Torsionally adaptive prosthesis with 1:3 coupling ratio, Device: Torsionally adaptive prosthesis with 1:2 coupling ratioAll participants will walk in a straight line while wearing the study prosthesis. |
| Circle walking with prosthesis inside | Experimental | Device: Torsionally adaptive prosthesis with 0:1 coupling ratio, Device: Torsionally adaptive prosthesis with 1:6 coupling ratio, Device: Torsionally adaptive prosthesis with 1:4 coupling ratio, Device: Torsionally adaptive prosthesis with 1:3 coupling ratio, Device: Torsionally adaptive prosthesis with 1:2 coupling ratioAll participants will walk around a 1-meter radius circle with their prosthesis on the inside of the circle. |
| Circle walking with prosthesis outside | Experimental | Device: Torsionally adaptive prosthesis with 0:1 coupling ratio, Device: Torsionally adaptive prosthesis with 1:6 coupling ratio, Device: Torsionally adaptive prosthesis with 1:4 coupling ratio, Device: Torsionally adaptive prosthesis with 1:3 coupling ratio, Device: Torsionally adaptive prosthesis with 1:2 coupling ratioAll participants will walk around a 1-meter radius circle with their prosthesis on the outside of the circle. |
Who may qualify
- Ages
- 18 to 70 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Unilateral transtibial amputation
- Been fit with a prosthesis and used it for at least six months
- Wear the prosthesis for four or more hours on an average day
- Prescribed prosthesis can accommodate fitment of the study prosthetic components to be tested (determined at initial visit)
Key exclusion criteria (6 listed)
- Improper fit and suspension with current prosthesis and one cannot be achieved with clinical resources (determined at initial visit)
- Current skin irritation or injury on residual limb
- Osteoarthritis, injury, or pain that interferes with walking ability
- Currently incarcerated
- Pregnant (determined via self-report)
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 |
|---|---|---|
| Torsionally adaptive prosthesis with 0:1 coupling ratioThe torsionally adaptive prosthesis can be programmed to couple the motion between the transverse- and sagittal-planes. A coupling ratio (transverse:sagittal) of 0:1 means there will be no coupling between the transverse- and sagittal-plane motion. That is, regardless of any motion in the sagittal plane, there will be zero motion in the transverse plane. | Device | Circle walking with prosthesis inside, Circle walking with prosthesis outside, Straight line walking |
| Torsionally adaptive prosthesis with 1:6 coupling ratioThe torsionally adaptive prosthesis can be programmed to couple the motion between the transverse- and sagittal-planes. A coupling ratio (transverse:sagittal) of 1:6 means there will be one degree of motion in the transverse plane for every six degrees of motion in the sagittal plane. | Device | Circle walking with prosthesis inside, Circle walking with prosthesis outside, Straight line walking |
| Torsionally adaptive prosthesis with 1:4 coupling ratioThe torsionally adaptive prosthesis can be programmed to couple the motion between the transverse- and sagittal-planes. A coupling ratio (transverse:sagittal) of 1:4 means there will be one degree of motion in the transverse plane for every four degrees of motion in the sagittal plane. | Device | Circle walking with prosthesis inside, Circle walking with prosthesis outside, Straight line walking |
| Torsionally adaptive prosthesis with 1:3 coupling ratioThe torsionally adaptive prosthesis can be programmed to couple the motion between the transverse- and sagittal-planes. A coupling ratio (transverse:sagittal) of 1:3 means there will be one degree of motion in the transverse plane for every three degrees of motion in the sagittal plane. | Device | Circle walking with prosthesis inside, Circle walking with prosthesis outside, Straight line walking |
| Torsionally adaptive prosthesis with 1:2 coupling ratioThe torsionally adaptive prosthesis can be programmed to couple the motion between the transverse- and sagittal-planes. A coupling ratio (transverse:sagittal) of 1:2 means there will be one degree of motion in the transverse plane for every two degrees of motion in the sagittal plane. | Device | Circle walking with prosthesis inside, Circle walking with prosthesis outside, Straight line walking |
Primary outcome
Peak Transverse-plane Prosthetic Socket Torque Normalized to Body Mass
Time frame: During walking trials for each coupling ratio
Peak transverse-plane prosthetic socket torque measured while walking normalized to body mass
1 secondary outcome
Satisfaction With the Prosthesis
Time frame: Immediately following walking trials for each coupling ratio
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 19 Nov 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Individual participant dataSharing planned: Yes. A de-identified, anonymized dataset in machine-readable format will be created and shared for all individual participant data (IPD) that underlie results in a publication. The investigators will follow 164.514(a) of the HIPAA Privacy Rule for de-identification of IPD.
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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.
Glenn K Klute, PhD principal investigator
VA Puget Sound Health Care System Seattle Division, Seattle, WA
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Torsionally adaptive prosthesis with 0:1 coupling ratio, Torsionally adaptive prosthesis with 1:6 coupling ratio and Torsionally adaptive prosthesis with 1:4 coupling ratio in people with Lower Extremity 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 6 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 19 Nov 2025. 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?
Yes. Results are posted in the registry (first posted 19 Nov 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
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?
Peak Transverse-plane Prosthetic Socket Torque Normalized to Body Mass (time frame: During walking trials for each coupling ratio). 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 19 Nov 2025.