Prosthetic Ankle-Foot System for Amputation

Overseen By Nicole Walker, MS

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: VA Office of Research and Development

Disqualifiers: Skin problems, Neurocognitive disorder, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 1 Jurisdiction This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 2

Duration: 6 months

18 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a new prosthetic ankle-foot system, the UNYQ Prosthetic Ankle-Feet System, designed to offer women Veterans with below-knee amputations more footwear options. The researchers aim to determine if this prosthesis improves body image and community involvement by enabling the use of various shoe types. The trial seeks women Veterans who have used a well-fitting prosthesis for at least six months and experience no skin issues on their residual limb. Participants will receive the new prosthetic system to assess whether it enhances their appearance and activities by allowing a wider variety of footwear. As an unphased trial, this study provides a unique opportunity for participants to explore new prosthetic options that could enhance their lifestyle and confidence.

Do I have to stop taking my current medications for the trial?

The trial protocol does not specify whether you need to stop taking your current medications.

What prior data suggests that this prosthetic ankle-foot system is safe for use?

Research shows that the UNYQ Prosthetic Ankle-Feet System is designed to be versatile and visually appealing for people with lower-limb amputations. However, current studies do not provide specific safety information for this system. As a new type of prosthetic, the trial is in the "Not Applicable" phase, focusing on evaluating the device's effectiveness rather than safety issues.

Powered ankle-foot prosthetics generally imitate natural movement, aiding in walking. They undergo thorough testing to ensure safety and comfort. This system is also designed to fit various types of shoes, potentially increasing user satisfaction.

Prospective trial participants should note that the system aims to enhance the user experience. Discussing any questions or concerns with the trial team is recommended for the most accurate and personalized information. ^{1 2 3 4 5}

Why are researchers excited about this trial?

The UNYQ Prosthetic Ankle-Feet System is unique because it offers enhanced customization options that improve the user's ability to wear a variety of footwear, a feature not commonly prioritized in traditional prosthetic designs. Most existing prosthetic feet focus primarily on basic functionality and stability, often at the expense of style and personal expression. Researchers are excited about this system because it combines functionality with aesthetics, potentially improving both the physical and emotional well-being of users. By allowing users to choose from a wider range of shoe styles, this prosthetic system supports a more active and confident lifestyle.

What evidence suggests that the UNYQ Prosthetic Ankle-Feet System is effective for improving footwear options for women Veterans with amputations?

Research has shown that the UNYQ Prosthetic Ankle-Feet System, which participants in this trial will receive, could significantly benefit veterans with leg amputations. This system works with various types of shoes by using 3D-printed foot shapes, allowing users to wear a wider variety of footwear. Early lab tests found that the prosthesis remains properly aligned even when switching shoes. This flexibility might enhance users' body image and increase their participation in community activities by providing more freedom in footwear choices. Additionally, the system is easy to produce using standard 3D printers. ^{1 4 6 7 8}

Who Is on the Research Team?

Andrew H Hansen, PhD

Principal Investigator

Minneapolis VA Health Care System, Minneapolis, MN

Are You a Good Fit for This Trial?

This trial is for US military women veterans with below-knee amputations who have been using a well-fitting prosthesis for at least 6 months. They should be able to use technology for video calls and data collection, and not have severe memory or concentration issues. Those with skin problems on the residual limb, too long of a limb, over 125 kg in mass, certain neurocognitive disorders, or maxed out body image/community participation scores can't join.

Inclusion Criteria

I have been using a permanent prosthesis for over 6 months.

Well fitting and well aligned prosthesis

Blessed Orientation-Memory-Concentration (Short Blessed) score between 0-6

Exclusion Criteria

My weight is over 125 kg.

I have a diagnosed condition like dementia affecting my daily activities.

Baseline ABIS-R or PROMIS-APSRA scores at the maximum levels (no room for improvement on primary outcomes)

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive a new prosthetic ankle-feet system designed to improve footwear options for 6 months in their home and community environments

6 months

Baseline, 1-month, 6-months

Follow-up

Participants are monitored for changes in body image and ability to participate in social roles and activities

6 months

1-month, 6-months

Dissemination and Closure

Final analysis and dissemination of results, closure of the project

6 months

What Are the Treatments Tested in This Trial?

Interventions

• UNYQ Prosthetic Ankle-Feet System

Trial Overview

The study tests the UNYQ Prosthetic Ankle-Feet System designed to allow veterans with leg amputations to wear various footwear. The new prosthetic foot can change shape and is made using 3D printing technology. It aims to improve satisfaction regarding fit and appearance of prostheses as well as enhance body image and community involvement.

How Is the Trial Designed?

Group I: Intervention Experimental Treatment 1 Intervention

Participants in this arm receive a new prosthesis system designed to improve footwear options.

UNYQ Prosthetic Ankle-Feet System is already approved in United States for the following indications:

Approved in United States as UNYQ Prosthetic Ankle-Feet System for:

• Lower limb amputations

Who Is Running the Clinical Trial?

VA Office of Research and Development

Lead Sponsor

Trials

1,691

Recruited

3,759,000+

University of Minnesota

Collaborator

Trials

1,459

Recruited

1,623,000+

Published Research Related to This Trial

A new modular prosthesis with inflatable air bladders has been developed to facilitate easier and faster mobilization for below-the-knee amputees, showing a higher compliance rate among users.

This device can be utilized immediately after surgery and until a permanent prosthesis is available, potentially improving recovery and mobility for amputees.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Airlimb. Initial experiences with a new immediate early management prosthesis with individually adjustable air chambers]. Ivanic, GM., Schon, LC., Badekas, T., et al.[2022]

The use of a dynamic-response prosthetic foot with a hydraulic ankle device (hyA-F) significantly reduces metabolic energy expenditure during walking in unilateral trans-tibial amputees, leading to improved locomotor efficiency.

HyA-F also enhances walking symmetry compared to a rigid prosthetic foot (rigA-F), particularly on declines, indicating better overall gait mechanics and reduced compensatory movements.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Energy cost of ambulation in trans-tibial amputees using a dynamic-response foot with hydraulic versus rigid 'ankle': insights from body centre of mass dynamics. Askew, GN., McFarlane, LA., Minetti, AE., et al.[2020]

The study developed a novel framework for creating customized passive-dynamic ankle-foot orthoses (PD-AFOs) using computer-aided design and rapid manufacturing techniques, achieving high dimensional accuracy within a 2 mm tolerance.

Subjective evaluations from two nondisabled participants indicated positive experiences with the customized PD-AFOs during gait, suggesting their potential effectiveness and comfort for users.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dimensional accuracy of ankle-foot orthoses constructed by rapid customization and manufacturing framework. Schrank, ES., Stanhope, SJ.[2022]

A new powered prosthetic ankle joint was developed to support both walking and running, showing the ability to mimic the necessary torque and angle for these activities at speeds up to 2.6 m/s.

While the system performed well in simulating ankle movements, it struggled to provide sufficient torque at higher running speeds (4 m/s), indicating that adjustments in spring stiffness are needed for optimal performance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A powered prosthetic ankle joint for walking and running. Grimmer, M., Holgate, M., Holgate, R., et al.[2023]

The Talaris Demonstrator (TD) prosthesis was evaluated in 42 participants with unilateral transtibial (TTA) and transfemoral (TFA) amputations, but it did not show significant improvements in overall task performance compared to their current prostheses during various mobility tests.

Subjective measures indicated that participants experienced increased comfort with the TD, particularly during inclined walking, suggesting potential benefits in user experience despite no significant differences in performance metrics.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Evaluation of an articulated passive ankle-foot prosthesis. Lathouwers, E., Ampe, T., Díaz, MA., et al.[2022]

In a study involving 13 unilateral transtibial prosthesis users, no significant difference in oxygen cost was found among five different prosthetic feet with varying forefoot flexibility, indicating that flexibility does not impact energy expenditure during walking.

Participants preferred prosthetic feet that better mimicked the flexibility of a natural ankle-foot system, as the most flexible foot (F1) received lower preference rankings compared to the biomimetic design (F3) and another moderately flexible foot (F4).

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of prosthetic foot forefoot flexibility on oxygen cost and subjective preference rankings of unilateral transtibial prosthesis users. Klodd, E., Hansen, A., Fatone, S., et al.[2022]

The 3D-printed segmented ankle foot orthosis (AFO) was successfully tested on a healthy subject for over 4 months, demonstrating durability and comfort during daily activities.

This AFO design allows for quick adjustments in bending stiffness through an interchangeable strut, making it a flexible option for orthotic practice.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Design of a segmented custom ankle foot orthosis with custom-made metal strut and 3D-printed footplate and calf shell. Funes-Lora, MA., Posh, R., Wensman, J., et al.[2023]

A systematic review of 28 studies on unilateral trans-tibial amputees found that Energy Storage And Return (ESAR) and Powered ankle-foot units (PWR) significantly adapt push-off power based on walking speed, unlike Solid Ankle Cushion Heel (SACH) units.

The study suggests that push-off power is a crucial factor in selecting prosthetic ankle-foot units, as ESAR and PWR showed strong correlations with walking speed, indicating their potential for better performance in varying walking conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Prosthetic push-off power in trans-tibial amputee level ground walking: A systematic review. Müller, R., Tronicke, L., Abel, R., et al.[2023]

In a pilot study involving two participants with Syme amputation, crossover prosthetic feet demonstrated increased ankle range of motion and energy return compared to traditional energy-storing feet, suggesting a more natural gait pattern.

Both participants preferred the crossover feet, indicating potential benefits in user satisfaction, although changes in patient-reported outcomes were not statistically significant.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of high-profile crossover feet on gait biomechanics in 2 individuals with Syme amputation. Slater, C., Hafner, BJ., Morgan, SJ.[2023]

Custom-made polypropylene orthoses, particularly the articulated hindfoot orthosis (HFO-A), allow for more natural gait patterns by limiting certain motions while maintaining others, making it potentially more comfortable and stable than rigid options.

The study found that orthoses with more rigid components, like the ankle-foot orthosis (AFO) and rigid hindfoot orthosis (HFO-R), restricted joint motion but led to less dynamic gait, indicating a trade-off between stability and natural movement.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of custom-made braces for the ankle and hindfoot on ankle and foot kinematics and ground reaction forces. Kitaoka, HB., Crevoisier, XM., Harbst, K., et al.[2013]

The proposed compact, lightweight ankle-foot prosthesis utilizes a novel non-backdrivable cam-based transmission to actively reposition the foot during swing phases, which can enhance foot clearance and adapt to ground inclines.

Preliminary tests indicate that this new design could improve gait energetics, symmetry, and comfort for transtibial amputees, addressing the limitations of heavier powered devices and the Össur PROPRIO FOOT.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A lightweight robotic ankle prosthesis with non-backdrivable cam-based transmission. Lenzi, T., Cempini, M., Newkirk, J., et al.[2018]

In a study of 738 individuals with amputations due to diabetes or vascular disease, those using microprocessor ankle-foot prosthetics showed the highest levels of functional mobility compared to other types.

The findings indicate that the choice of prosthetic ankle-foot mechanism significantly affects mobility outcomes, highlighting the importance of selecting appropriate technology for rehabilitation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Mobility analysis of AmpuTees (MAAT 5): Impact of five common prosthetic ankle-foot categories for individuals with diabetic/dysvascular amputation. Wurdeman, SR., Stevens, PM., Campbell, JH.[2022]

The study involving 12 unilateral transtibial amputees found that using a microprocessor-controlled prosthetic ankle significantly affects socket pressure, with the highest pressures occurring during incline walking, indicating potential risks for pressure-related issues.

Adjusting the angle of the prosthetic ankle during different walking conditions can help reduce socket pressure, suggesting that personalized fitting and adaptation of prosthetic devices are crucial for optimizing comfort and safety.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pressure characteristics at the stump/socket interface in transtibial amputees using an adaptive prosthetic foot. Wolf, SI., Alimusaj, M., Fradet, L., et al.[2013]

Citations

1.

withpower.com

withpower.com/trial/phase-amputations-6-2023-13ea4

Prosthetic Ankle-Foot System for Amputation

Trial Overview The study tests the UNYQ Prosthetic Ankle-Feet System designed to allow veterans with leg amputations to wear various footwear. The new ...

2.

rc.umn.edu

rc.umn.edu/project/creating-adaptable-foot-prosthesis

Creating an Adaptable Foot Prosthesis

A modular ankle-feet system incorporating additive manufactured foot shapes designed to match nearly any pair of shoes.

3.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC12118934/

Functional dynamic prosthesis alignment maintained across ...

Using the modular prosthetic ankle-feet system, participants completed five walking trials per foot-shoe set in the motion analysis laboratory.

4.

journals.plos.org

journals.plos.org/plosone/article?id=10.1371/journal.pone.0323647

Functional dynamic prosthesis alignment maintained across ...

The primary aim of this study was to understand if clinically acceptable prosthesis alignment is maintained as prosthesis users change between modular foot- ...

5.

sciencedirect.com

sciencedirect.com/science/article/pii/S0264127525003387

3D-printed prosthetic foot design: Mechanical similarity and ...

This study introduces a novel, accessible approach for designing a lower-limb prosthetic foot intended for production on standard 3D printers.

6.

livingwithamplitude.com

livingwithamplitude.com/article/amputee-prosthetics-unyq-foot-has-heeling-power/

For Amputees, UNYQ Foot Holds Heeling Power

The new UNYQ Foot gives lower-limb amputees a versatile, aesthetically appealing prosthetic foot that functions well with a wide selection ...

7.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC10858430/

Effects of a Powered Ankle-Foot Prosthesis and Physical ...

Powered ankle-foot prosthetic devices can generate net positive mechanical work during gait, which mimics the physiological ankle.

8.

researchgate.net

researchgate.net/publication/392164227_Functional_dynamic_prosthesis_alignment_maintained_across_varying_footwear_using_a_modular_prosthetic_ankle-feet_system

Functional dynamic prosthesis alignment maintained ...

Using the modular prosthetic ankle-feet system, participants completed five walking trials per foot-shoe set in the motion analysis laboratory.