Prosthetic Foot Adaptability for Amputation

Recruiting at2 trial locations

Overseen by Murray Maitland, PT, PhD

Age: Any Age

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Academic

Recruiting

Sponsor: University of Washington

Disqualifiers: Skin wounds, Parkinson's, Alcoholism, others

No Placebo Group

Trial Summary

What is the purpose of this trial?

People with lower extremity amputation (LEA) have persistent problems with balance, falls, residual limb pain, functional mobility, cognitive attention during gait, and satisfaction with participation in daily activities, despite using prostheses. The purpose of this randomized clinical trial is to advance understanding of how dynamic foot design features may help people with LEA This study will include people with above-knee amputations, or with bilateral amputations, or with below-knee amputations and lower levels of mobility. The main study questions/goals are: 1a) To determine if frontal plane adaptation in a foot prosthesis impacts performance, comfort, activities of daily living, and community mobility in the study populations. To answer this question, we will compare a locked and unlocked version of the novel prosthesis. 1b) To determine how the unlocked investigational foot condition compares to the person's usual foot using the outcomes listed above. 2) To examine the participants' lived experience during community activities. The study will use performance tests, questionnaires, logbooks, and interviews to monitor person-centered outcomes and perceptions of personal functioning during the use of the investigational foot (locked and unlocked) compared to the person's usual foot.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It seems focused on prosthetic foot use, so it's best to discuss your medications with the trial team.

What data supports the effectiveness of the treatment META-Arc foot for amputation?

The study on the use of a microprocessor knee (C-Leg) with an appropriate foot suggests that advanced prosthetic components can improve safety and performance in individuals with lower limb amputations, potentially indicating benefits for the META-Arc foot as well. ^{1 2 3 4 5}

How does the META-Arc foot treatment differ from other prosthetic foot options for amputees?

The META-Arc foot is unique because it features a polycentric ankle joint that allows for more natural movement in the frontal plane, making it easier for users to walk on uneven terrain. This adaptability is not typically found in other prosthetic feet, which often have limited movement and can make walking on uneven surfaces challenging. ^{6 7 8 9 10}

Research Team

Murray Maitland, PT, PhD

Principal Investigator

University of Washington

Eligibility Criteria

This trial is for individuals with above-knee amputations, bilateral amputations, or below-knee amputations who have lower mobility levels. It aims to help them with balance, pain, and daily activities by testing a new type of foot prosthesis.

Inclusion Criteria

I have been using a prosthesis for over a year since my amputation.

I can walk more than 400 meters without feeling more pain.

People must have the ability to read, write, and comprehend English.

Exclusion Criteria

Participants must not have conditions such as skin wounds that preclude the use of a prosthesis.

I do not have conditions like Parkinson's, alcoholism, brain tumor, or hereditary cerebellar ataxias that could affect my walking.

I can walk with help but don't mainly use a wheelchair.

Trial Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

A1 Phase

Participants use their usual prosthetic foot and complete baseline assessments

2 weeks

1 visit (in-person)

B1 Phase

Participants use the investigational foot with either locked or unlocked linkage and perform community activities

2 weeks

1 visit (in-person), daily logbook entries

B2 Phase

Participants continue using the investigational foot with the opposite linkage condition and perform community activities

2 weeks

1 visit (in-person), daily logbook entries

A2 Phase

Participants return to using their usual prosthetic foot and reflect on differences

2 weeks

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after the trial phases

4 weeks

Treatment Details

Interventions

• META-Arc foot locked (Prosthesis)
• META-Arc foot unlocked (Prosthesis)

Trial Overview The study tests a novel foot prosthesis in two modes: locked and unlocked. Participants will be randomly assigned to use either mode and their usual prosthetic foot to compare performance, comfort, and mobility.

Participant Groups

Group I: Unlocked ankle articulation Experimental Treatment 1 Intervention

The design is a randomized cross-over clinical trial following an A1-B1-B2-A2 design. In the unlocked condition, the 20 degree of frontal plane ankle motion is enabled. The A conditions will be with the usual foot. The B conditions are randomized to the locked and unlocked investigational foot.

Group II: Locked ankle articulation Experimental Treatment 1 Intervention

The design is a randomized cross-over clinical trial following an A1-B1-B2-A2 design. In the locked condition, the 20 degree of frontal plane ankle motion is eliminated by a physical lock. The A conditions will be with the usual foot. The B conditions are randomized to the locked and unlocked investigational foot.

Who Is Running the Clinical Trial?

University of Washington

Lead Sponsor

Trials

1,858

Recruited

2,023,000+

Dr. Timothy H. Dellit

University of Washington

Chief Executive Officer since 2023

MD from University of Washington

Dr. Anneliese Schleyer

University of Washington

Chief Medical Officer since 2023

MD, MHA

United States Department of Defense

Collaborator

Trials

940

Recruited

339,000+

Pete Hegseth

United States Department of Defense

Chief Executive Officer

Bachelor's degree in Political Science from Princeton University, JD from Harvard Law School

Lisa Hershman

United States Department of Defense

Chief Medical Officer since 2021

MD from Uniformed Services University of the Health Sciences

Findings from Research

A study involving 10 individuals with unilateral transtibial amputation found that a novel 3D-printed prosthetic foot (ComfyStep) showed significant biomechanical differences compared to conventional prosthetic feet, including reduced range of motion and increased stiffness.

While the 3D-printed foot allows for more individualized adjustments, the differences observed raise questions about its clinical relevance, suggesting that improvements in design, particularly in stiffness, could enhance its performance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Biomechanical comparison of a 3D-printed prosthetic foot with conventional feet in people with transtibial amputation: A prospective cohort study. Trinler, U., Heitzmann, DWW., Hitzeroth, S., et al.[2023]

Individuals with unilateral lower limb amputation exhibit distinct turning strategies, spending more time on their intact limb compared to their prosthetic limb during a 180˚ turn, with transfemoral amputees showing even greater reliance on their intact limb than transtibial amputees.

The Component Timed-Up-and-Go (cTUG) test can effectively capture these differences in turning performance, which may inform prosthetic prescription and physical therapy interventions for amputees.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Temporal-Spatial Values During a 180° Step Turn in People with Unilateral Lower Limb Amputation. Clemens, SM., Klute, GK., Kirk-Sanchez, NJ., et al.[2022]

Older adults with lower limb amputation reported significant adjustments in their lives post-amputation, highlighting the long-term impact of this experience.

Participants using the self-aligning ankle-foot (SA-AF) prosthetic reported less pain and greater mobility, indicating its acceptability and effectiveness, which supports the need for further research in a full-scale randomized controlled trial.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

'A whole different ball game': the qualitative experience of older adults with a transtibial amputation and the use of a self-aligning prosthetic ankle-foot on the STEPFORWARD trial. Mitchell, N., Leggett, H., Watson, J., et al.[2023]

A 13-month clinical trial with 10 participants (average age 63) showed that individuals with transfemoral amputations classified as MFCL level K2 experienced significant improvements in gait performance, safety, and self-reported mobility when using a microprocessor-controlled knee (MPK) combined with a 1M10 foot, compared to their previous non-microprocessor knee (NMPK).

The improvements in clinical scores for gait speed, balance, and fall safety were comparable to those seen in individuals with a higher functional level (K3), suggesting that advanced prosthetic technology can enhance the quality of life for K2 level amputees.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Using a microprocessor knee (C-Leg) with appropriate foot transitioned individuals with dysvascular transfemoral amputations to higher performance levels: a longitudinal randomized clinical trial. Jayaraman, C., Mummidisetty, CK., Albert, MV., et al.[2022]

In a study of 17 patients with lower limb amputations, bone-anchored prostheses showed a high implant survival rate of 90% at 2 years, 70% at 10 years, and 60% at 15 years, indicating long-term reliability.

Despite a significant improvement in functional scores for patients, 65% experienced mechanical complications and 76% had infections, primarily stage 1 infections, highlighting the need for careful monitoring post-surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Bone-anchored prostheses for lower limb amputation in a French cohort with 1-15 years of follow-up: implant survival rates, mechanical complications, and reported outcomes. Thouvenin, C., Bertrand-Marchand, M., Klotz, R., et al.[2023]

The META Arc prosthetic foot, featuring a polycentric ankle joint, significantly improves adaptability in the frontal plane and reduces lateral forces compared to six other commercially available prosthetic feet during testing on uneven terrain.

This design allows for better stability while walking without compromising forward motion performance, suggesting it could enhance the overall mobility of prosthesis users.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Mechanical testing of frontal plane adaptability of commercially available prosthetic feet. Wernke, MM., Ficanha, EM., Thomas, Z., et al.[2022]

Microprocessor Prosthetic Ankles (MPA) provide better ankle angle adaptation for transtibial amputees compared to traditional energy storing and return (ESR) feet, particularly during varied walking conditions like slopes and stairs.

However, while MPAs improve adaptability, they tend to release less energy for propulsion, indicating a trade-off between flexibility and energy efficiency in different prosthetic designs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Experimental characterization of the moment-angle curve during level and slope locomotion of transtibial amputee: Which parameters can be extracted to quantify the adaptations of microprocessor prosthetic ankle? Davot, J., Thomas-Pohl, M., Villa, C., et al.[2021]

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]

A robotic prosthetic foot emulator (PFE) can accurately replicate the effective ankle stiffness of various commercial prosthetic forefeet, achieving an average accuracy within 1% of the actual feet tested.

This technology allows prosthesis users to trial different foot types based on their mechanical characteristics, potentially improving the decision-making process for prosthetic foot selection and enhancing user satisfaction.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Emulating the Effective Ankle Stiffness of Commercial Prosthetic Feet Using a Robotic Prosthetic Foot Emulator. Halsne, EG., Curran, CS., Caputo, JM., et al.[2022]

Transtibial amputees using dynamic elastic response prostheses (like Seattle-Lite and Flex Foot) still walk slower and have shorter strides compared to non-amputee controls, indicating that these advanced designs do not fully restore normal mobility.

The study found that the timing and velocity of movements in the early stance phase were significantly delayed in amputees, which compromised their stability and suggests that future prosthetic designs should focus on improving ankle mobility to better mimic natural movement.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Segment velocities in normal and transtibial amputees: prosthetic design implications. Rao, SS., Boyd, LA., Mulroy, SJ., et al.[2022]

References

1. France pubmed.ncbi.nlm.nih.gov

Biomechanical comparison of a 3D-printed prosthetic foot with conventional feet in people with transtibial amputation: A prospective cohort study. [2023]

2. England pubmed.ncbi.nlm.nih.gov

Temporal-Spatial Values During a 180° Step Turn in People with Unilateral Lower Limb Amputation. [2022]

3. England pubmed.ncbi.nlm.nih.gov

'A whole different ball game': the qualitative experience of older adults with a transtibial amputation and the use of a self-aligning prosthetic ankle-foot on the STEPFORWARD trial. [2023]

4. England pubmed.ncbi.nlm.nih.gov

Using a microprocessor knee (C-Leg) with appropriate foot transitioned individuals with dysvascular transfemoral amputations to higher performance levels: a longitudinal randomized clinical trial. [2022]

5. France pubmed.ncbi.nlm.nih.gov

Bone-anchored prostheses for lower limb amputation in a French cohort with 1-15 years of follow-up: implant survival rates, mechanical complications, and reported outcomes. [2023]

6. England pubmed.ncbi.nlm.nih.gov

Mechanical testing of frontal plane adaptability of commercially available prosthetic feet. [2022]

7. England pubmed.ncbi.nlm.nih.gov

Experimental characterization of the moment-angle curve during level and slope locomotion of transtibial amputee: Which parameters can be extracted to quantify the adaptations of microprocessor prosthetic ankle? [2021]

8. United States pubmed.ncbi.nlm.nih.gov

A lightweight robotic ankle prosthesis with non-backdrivable cam-based transmission. [2018]

9. United States pubmed.ncbi.nlm.nih.gov

Emulating the Effective Ankle Stiffness of Commercial Prosthetic Feet Using a Robotic Prosthetic Foot Emulator. [2022]

10. United States pubmed.ncbi.nlm.nih.gov

Segment velocities in normal and transtibial amputees: prosthetic design implications. [2022]