Hybrid Prosthetic Leg for Amputation

Overseen By Levi Hargrove, PhD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Shirley Ryan AbilityLab

Disqualifiers: Cognitive impairment, Significant new injury, 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: Unknown

20 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

The objective of this research is to determine the clinical benefits of an innovative and lightweight powered leg controlled using our intent recognition framework in laboratory and community environments.

Will I have to stop taking my current medications?

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

Is the Hybrid Prosthetic Leg generally safe for human use?

Research on lower limb prostheses highlights the importance of safety during testing and training, as users may risk losing balance, which can lead to injury. A stepwise safety protocol has been designed to manage these risks, ensuring that each safety level is achieved before moving to the next stage, from lab testing to real-world use. ^{1 2 3 4 5}

How is the Hybrid Prosthetic Leg treatment different from other treatments for amputation?

The Hybrid Prosthetic Leg is unique because it combines active and passive components, allowing it to provide power for activities like stair climbing while remaining lightweight and efficient for everyday use. It features a self-energized system that stores energy during passive movements and uses it to enhance walking, offering a more natural gait and improved mobility compared to traditional prostheses. ^{6 7 8 9 10}

What data supports the effectiveness of the treatment Hybrid Prosthetic Leg for Amputation?

Research shows that powered prosthetic legs, which are part of the Hybrid Prosthetic Leg treatment, can help amputees walk more naturally and adapt to different walking conditions like stairs and ramps. Additionally, early use of prosthetics after amputation can improve physical and psychological outcomes, making the treatment more effective. ^{11 12 13 14 15}

Who Is on the Research Team?

Levi Hargrove, PhD

Principal Investigator

Shirley Ryan AbilityLab

Are You a Good Fit for This Trial?

This trial is for individuals with a single or double lower limb amputation who currently use a prosthesis and can walk at various speeds (K2/K3/K4 level). Participants must speak English to understand the study and give feedback. Those with cognitive impairments, other serious health issues, or new injuries that prevent prosthesis use cannot join.

Inclusion Criteria

I have had one or both of my legs amputated.

English speaking

I can walk with a prosthesis.

Exclusion Criteria

I understand and can follow the study's requirements.

Significant other comorbidity: Any other medical issues or injuries that would preclude completion of the study, use of the prostheses, or that would otherwise prevent acquisition of useable data by researchers.

I can wear a prosthesis and do daily tasks without major new injuries.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

In-lab Therapy

Participants are fit with the Hybrid Leg and receive in-lab therapy to learn how to ambulate with the device

Duration not specified

Multiple in-lab visits

Ambulation and Community Mobility Training

Subjects complete extensive ambulation and community mobility training to learn optimal use of their own passive device or the Hybrid Leg

Duration not specified

Multiple in-lab visits

Home Trial

Subjects complete 4-week trials using their assigned prosthesis (Condition A or B) at home and within their community

4 weeks

Home-based monitoring

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Hybrid Leg
• Prescribed Passive Prosthesis

Trial Overview The study tests an advanced powered prosthetic leg called 'Hybrid Leg' against the standard passive prosthesis prescribed to patients. The Hybrid Leg uses a special system designed to recognize the user's movement intentions in both lab settings and everyday life scenarios.

How Is the Trial Designed?

Group I: Condition B: Passive Leg Experimental Treatment 1 Intervention

Subject will use their currently prescribed home passive prosthesis

Group II: Condition A: Hybrid Leg Experimental Treatment 1 Intervention

Subject will be trained on use of the experimental device, the Hybrid Leg.

Who Is Running the Clinical Trial?

Shirley Ryan AbilityLab

Lead Sponsor

Trials

212

Recruited

17,900+

Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

Collaborator

Trials

2,103

Recruited

2,760,000+

Published Research Related to This Trial

In a study of 169 patients over 15 years, male gender and transtibial amputation were identified as strong predictors of successful prosthetic rehabilitation, while the presence of ulcers in the preserved limb was linked to rehabilitation failure.

Older age (especially over 65) and comorbidities were significant predictors of failed rehabilitation, highlighting the importance of timely physical therapy for improving walking ability post-amputation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Predicting successful prosthetic rehabilitation in major lower-limb amputation patients: a 15-year retrospective cohort study. Fajardo-Martos, I., Roda, O., Zambudio-Periago, R., et al.[2022]

Early ambulation after lower extremity amputation significantly improves functional and psychological outcomes, reduces risks associated with immobility, and enhances prosthetic compliance.

An indigenously developed, cost-effective temporary prosthesis allows for immediate fitting and early weight bearing, which helps prevent complications and increases acceptance among patients, particularly in Third World nations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A cost-effective, adjustable, femoral socket, temporary prosthesis for immediate rehabilitation of above-knee amputation. Sathishkumar, S., Manigandan, C., Asha, T., et al.[2022]

In a study involving 10 individuals with unilateral transtibial limb loss, standardized functional prosthetic gait training did not show significant improvements in self-report measures or performance-based tests, except for the Amputee Mobility Predictor (AMPPRO) in those with peripheral vascular disease (PVD).

The Proprio foot demonstrated significant differences in mobility outcomes compared to other prosthetic feet, particularly in the AMPPRO and 6-minute walk test (6MWT), highlighting its potential benefits for users with PVD.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Application of self-report and performance-based outcome measures to determine functional differences between four categories of prosthetic feet. Gailey, RS., Gaunaurd, I., Agrawal, V., et al.[2022]

The study developed a new method for configuring powered knee and ankle prostheses that significantly reduces the time needed to set them up for different walking modes, cutting the initial accommodation period by 56% to under 5 hours.

By using modified intrinsic control strategies, only 17% of the configuration parameters needed adjustment for novice users, making it easier for amputees to transition to using these advanced prosthetic devices.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Configuring a powered knee and ankle prosthesis for transfemoral amputees within five specific ambulation modes. Simon, AM., Ingraham, KA., Fey, NP., et al.[2022]

In a study of 112 patients with unilateral trans-tibial amputation, only 50% were fitted with a prosthesis at 6 months, with an additional 13% fitted by 8 years, highlighting challenges in prosthetic adoption post-amputation.

Significant predictors for receiving a prosthesis included younger age at amputation, ability to walk outdoors before the amputation, and being male, suggesting that these factors could guide patient management and rehabilitation strategies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Outcome after trans-tibial amputation for vascular disease. A follow-up after eight years. Hermodsson, Y., Ekdahl, C., Persson, BM.[2022]

The study evaluated 14 different prosthetic feet for their energy storing and releasing capabilities using a young male amputee, ranking them based on total energy at the ankle joint during walking on level and sloped surfaces.

The top-performing prosthetic feet, which stored and released the most energy, were Flex-Walk, SAFE II, and High Function, while the subject preferred feet that absorbed more energy but released less, indicating a preference for comfort over energy return.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Energy storing property of so-called energy-storing prosthetic feet. Ehara, Y., Beppu, M., Nomura, S., et al.[2006]

A structured protocol for testing lower limb prostheses emphasizes safety, requiring users to meet specific graded safety levels before progressing to more challenging environments.

This approach aims to reduce the risk of falls and injuries, thereby enhancing user confidence and overall experience with active prosthetic legs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Design of a stepwise safety protocol for lower limb prosthetic risk management in a clinical investigation. Thesleff, A., Ahkami, B., Anderson, J., et al.[2022]

A study involving 15 lower limb prosthesis users found that patient-centered decision trees are effective tools for guiding users in self-managing socket fit issues, with 80% of participants agreeing on their acceptability.

The decision trees were particularly beneficial for new prosthesis users, as they provided clear solutions and used terminology that was easy to understand, while more experienced users may prefer to rely on their own self-management skills.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Development and acceptability testing of decision trees for self-management of prosthetic socket fit in adults with lower limb amputation. Lee, DJ., Veneri, DA.[2022]

The study assessed the reliability and measurement error of performance-based clinical tests in 60 unilateral lower limb prosthesis (LLP) users, finding high interrater reliability (≥0.98) for all tests, indicating consistent results across different raters.

Test-retest reliability varied, with the Four Square Step Test showing the highest reliability (ICC of 0.97), while the Timed 'Up and Go' test had a lower reliability (ICC of 0.88), suggesting that most tests are suitable for clinical use in monitoring balance and mobility in LLP users.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Interrater and Test-Retest Reliability of Performance-Based Clinical Tests Administered to Established Users of Lower Limb Prostheses. Sawers, A., Kim, J., Balkman, G., et al.[2020]

A study involving 29 active lower limb prosthesis users identified key themes related to mobility, which will help develop new items for the Prosthetic Limb Users Survey of Mobility (PLUS-M) to better assess the abilities of highly active individuals.

Participants highlighted the importance of understanding mobility characteristics, such as postural changes and terrain challenges, which can inform rehabilitation practices and improve access to specialized prosthetic components for enhanced mobility.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Mobility with a lower limb prosthesis: experiences of users with high levels of functional ability. Morgan, SJ., Liljenquist, KS., Kajlich, A., et al.[2022]

The new robotic leg prosthesis effectively mimics the biomechanics of a biological leg while matching the weight, size, and battery life of traditional prostheses, making it more practical for daily use.

Preclinical tests with three individuals showed that this prosthesis allows for natural walking movements and includes a passive mode for unlimited walking on level ground without needing to recharge, which is a significant advancement over existing powered prosthetics.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A lightweight robotic leg prosthesis replicating the biomechanics of the knee, ankle, and toe joint. Tran, M., Gabert, L., Hood, S., et al.[2023]

The experimental adaptive controlled knee prosthesis significantly improved walking performance in amputees compared to a normal prosthesis, showing a 50% increase in hip moment peaks and a 37% reduction in hip muscular effort.

Additionally, the adaptive knee reduced the need for compensatory movements and enhanced walking symmetry, indicating its potential for better functional outcomes in amputees.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Evaluation of AK prostheses comparing conventional with adaptive knee control devices. Ishai, G., Bar, A.[2019]

The Hybrid Knee prosthesis is designed to provide powered assistance specifically for stair climbing while remaining lightweight and passive for other activities like level-ground walking and stair descent.

Preliminary tests with both an able-bodied user and a transfemoral amputee showed low error rates in the system's ability to recognize when to switch between active and passive control, indicating effective intent recognition for improved ambulation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Ambulation Control System Design for a Hybrid Knee Prosthesis. Simon, AM., Ursetta, F., Shah, K., et al.[2022]

Current lower limb prostheses lack the ability to replicate the energy distribution and function of natural musculature, which is crucial for effective movement.

The proposed above-knee prosthesis incorporates a self-energized mechanism that captures and stores energy from passive movements at the knee and ankle, enabling active plantar-flexion and improving locomotion efficiency.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Active plantar-flexion above-knee prosthesis: concept and preliminary design. Rigas, C.[2017]

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]

Citations

1. Brazil pubmed.ncbi.nlm.nih.gov

Predicting successful prosthetic rehabilitation in major lower-limb amputation patients: a 15-year retrospective cohort study. [2022]

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

A cost-effective, adjustable, femoral socket, temporary prosthesis for immediate rehabilitation of above-knee amputation. [2022]

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

Application of self-report and performance-based outcome measures to determine functional differences between four categories of prosthetic feet. [2022]

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

Configuring a powered knee and ankle prosthesis for transfemoral amputees within five specific ambulation modes. [2022]

5. Sweden pubmed.ncbi.nlm.nih.gov

Outcome after trans-tibial amputation for vascular disease. A follow-up after eight years. [2022]

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

Energy storing property of so-called energy-storing prosthetic feet. [2006]

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

Design of a stepwise safety protocol for lower limb prosthetic risk management in a clinical investigation. [2022]

8. England pubmed.ncbi.nlm.nih.gov

Development and acceptability testing of decision trees for self-management of prosthetic socket fit in adults with lower limb amputation. [2022]

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

Interrater and Test-Retest Reliability of Performance-Based Clinical Tests Administered to Established Users of Lower Limb Prostheses. [2020]

10. England pubmed.ncbi.nlm.nih.gov

Mobility with a lower limb prosthesis: experiences of users with high levels of functional ability. [2022]

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

A lightweight robotic leg prosthesis replicating the biomechanics of the knee, ankle, and toe joint. [2023]

12. England pubmed.ncbi.nlm.nih.gov

Evaluation of AK prostheses comparing conventional with adaptive knee control devices. [2019]

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

Ambulation Control System Design for a Hybrid Knee Prosthesis. [2022]

14. France pubmed.ncbi.nlm.nih.gov

Active plantar-flexion above-knee prosthesis: concept and preliminary design. [2017]

15. France pubmed.ncbi.nlm.nih.gov

Effects of high-profile crossover feet on gait biomechanics in 2 individuals with Syme amputation. [2023]