ENABLE Sensing Pad for Prosthetic Leg Fitting in Below Knee Amputees

(ENABLE Trial)

Overseen By He Huang, PhD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: North Carolina State University

Disqualifiers: Cognitive impairment, Visual impairment, Neuropathy, others

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

Compensation: Varies

Number of Visits: Unknown

3 Participants Needed

Trial Summary

What is the purpose of this trial?

Lower limb amputees (LLA) rely on their prosthetic legs to remain active and lead an independent life. For most LLAs, a well-fitted prosthetic socket is the only option to interface with their prosthetic leg, however, it is a real challenge to make a prosthetic socket to interface with residual limbs accurately. One of the reasons is that there lack of accurate approaches to evaluate the pressure distribution on the residual limb accurately and effectively. To overcome this issue, the research team will develop an innovative sensing system, which permits the prosthetists to track the pressure distribution on the residual limb visually. The capability of the new sensing system will be demonstrated on lower limb amputees.

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

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

What data supports the idea that ENABLE Sensing Pad for Prosthetic Leg Fitting in Below Knee Amputees is an effective treatment?

The available research shows that a low-cost, portable sensor system, similar to the ENABLE Sensing Pad, was validated for use in prosthetic socket applications. This system was found to be accurate and reliable when compared to a commercial sensor system during fitting sessions for below-knee prosthetic users. This suggests that the ENABLE Sensing Pad could effectively help in achieving a better fit between the limb and the prosthetic socket, which is crucial for comfort and safety. ^{1 2 3 4 5}

What safety data exists for the ENABLE Sensing Pad for prosthetic leg fitting?

The research does not directly mention safety data for the ENABLE Sensing Pad or its other names. However, related studies discuss safety protocols and validation of sensor systems for prosthetic fittings. One study presents a safety protocol for lower limb prosthetic risk management, emphasizing graded safety levels from lab testing to real-world use. Another study validates a custom interface pressure measurement system for prosthetic sockets, showing it to be accurate and reliable in clinical settings. These studies suggest a focus on safety and validation in prosthetic fitting technologies, which may be relevant to the ENABLE Sensing Pad. ^{1 2 6 7 8}

Is the ENABLE Sensing Pad a promising treatment for fitting prosthetic legs in below-knee amputees?

Yes, the ENABLE Sensing Pad is a promising treatment because it helps make prosthetic leg fitting more efficient and comfortable for below-knee amputees. It can reduce the time needed to adjust the prosthetic leg, allowing users to quickly experience the benefits of improved mobility and comfort. ^{2 9 10 11 12}

Eligibility Criteria

This trial is for individuals with a below-knee amputation who have been using their current prosthetic socket for at least 6 months without major issues. They should be able to walk comfortably for 3 minutes and have over a year's experience with their prosthetic leg. People with cognitive or visual impairments, pregnant women, or those with neuropathy in the residual limb cannot participate.

Inclusion Criteria

I can walk for 3 minutes without needing to rest.

I have used my prosthetic leg for at least a year.

The bone in my amputated leg is more than half as long as the one in my other leg.

Exclusion Criteria

I experience nerve pain in the part of my limb that was amputated.

I do not have any cognitive or visual problems that would prevent me from understanding or following instructions.

Pregnant female

Treatment Details

Interventions

• ENABLE Sensing Pad
• Insert Small Pads at Pressure Tolerant Locations

Trial Overview The study is testing an innovative ENABLE system designed to assess how well a prosthetic socket fits by tracking pressure distribution on the residual limb visually. Participants will use small pads and an ENABLE sensing pad within their usual prosthesis setup.

Participant Groups

Group I: Transtibial patient Experimental Treatment 2 Interventions

All the recruited participants will be included in this arm and will go through the socket manufacturing, fitting, and testing procedure.

Who Is Running the Clinical Trial?

North Carolina State University

Lead Sponsor

Trials

38

Recruited

50,000+

Findings from Research

A new low-cost, portable, wireless sensor system has been developed to measure pressure at the socket-limb interface during prosthetic fitting, which is crucial for safety and fit.

In clinical tests with three transtibial prosthesis users, this new sensor system showed comparable accuracy to a commercial system, indicating its potential for effective use in prosthetic socket manufacture.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Validation of a Custom Interface Pressure Measurement System to Improve Fitting of Transtibial Prosthetic Check Sockets. Armitage, L., Cho, K., Sariyildiz, E., et al.[2023]

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]

A study of 120 unilateral transtibial prosthesis users found that the six-minute walk test (6MWT) and one-leg standing test on prosthesis (OLSTP) can effectively predict the functional K-level of patients, which is crucial for appropriate prosthesis prescription.

Using a simple classification rule based on 6MWT results, the study achieved nearly 90% sensitivity and specificity in distinguishing between different K-levels, suggesting these tests could enhance clinical decision-making in rehabilitation programs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Establishing K-levels and prescribing transtibial prostheses using six-minute walk test and one-leg standing test on prosthesis: a retrospective audit. Majdič, N., Vidmar, G., Burger, H.[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]

High self-efficacy in individuals with lower-limb amputations is associated with increased prosthetic use, better mobility, and fewer amputation-related problems, as shown in a study of 42 participants using either microprocessor-controlled or non-microprocessor-controlled prosthetic knees.

There was no significant difference in outcomes between users of microprocessor-controlled and non-microprocessor-controlled prosthetic knees, suggesting that self-efficacy may play a more critical role in rehabilitation than the type of prosthetic knee used.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Perceived self-efficacy and specific self-reported outcomes in persons with lower-limb amputation using a non-microprocessor-controlled versus a microprocessor-controlled prosthetic knee. Möller, S., Hagberg, K., Samulesson, K., et al.[2022]

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]

The study introduces an automatic control system for adjustable transtibial prosthetic sockets that actively adapts to interfacial loading, potentially reducing the risk of soft tissue injuries for users with lower limb amputations.

Using finite element analysis, the system was able to maintain safe interfacial pressure levels during activities of daily living, demonstrating effective actuation rates that could enhance comfort and functionality for individuals with sensory impairments.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Developing a control framework for self-adjusting prosthetic sockets incorporating tissue injury risk estimation and generalized predictive control. Mbithi, FM., Chipperfield, AJ., Steer, JW., et al.[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 case study demonstrated that lightweight powered knee and ankle prostheses can effectively restore natural leg movements for individuals with bilateral above-knee amputations, allowing them to walk and climb stairs with improved gait patterns.

The powered prostheses were able to replicate essential biomechanical functions, such as ankle push-off during walking and knee power generation during stair ascent, which are crucial for enhancing mobility and quality of life.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Powered knee and ankle prostheses enable natural ambulation on level ground and stairs for individuals with bilateral above-knee amputation: a case study. Hood, S., Creveling, S., Gabert, L., et al.[2023]

Modified control strategies for powered knee and ankle prostheses significantly reduced the number of tuning parameters from 140 to just 21, making it easier to configure the device for individuals with transfemoral amputations.

The new strategies allowed three participants to walk comfortably and safely across various ambulation modes, while maintaining kinematic and kinetic patterns similar to those of non-amputee individuals.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Strategies to reduce the configuration time for a powered knee and ankle prosthesis across multiple ambulation modes. Simon, AM., Fey, NP., Finucane, SB., et al.[2022]

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]

The study introduces a new sitting mode to a previously developed knee and ankle prosthesis control system, enhancing its functionality for users during transitions between sitting and standing.

Experimental results with a transfemoral amputee show that the prosthesis can effectively recognize the user's intent to sit or stand based on sensor signals, generating and dissipating significant power (up to 50 W) during these movements, which indicates its active engagement in assisting the user.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Powered Sit-to-Stand and Assistive Stand-to-Sit Framework for a Powered Transfemoral Prosthesis. Varol, HA., Sup, F., Goldfarb, M.[2021]

References

1. Switzerland pubmed.ncbi.nlm.nih.gov

Validation of a Custom Interface Pressure Measurement System to Improve Fitting of Transtibial Prosthetic Check Sockets. [2023]

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

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

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

Establishing K-levels and prescribing transtibial prostheses using six-minute walk test and one-leg standing test on prosthesis: a retrospective audit. [2022]

4. 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]

5. England pubmed.ncbi.nlm.nih.gov

Perceived self-efficacy and specific self-reported outcomes in persons with lower-limb amputation using a non-microprocessor-controlled versus a microprocessor-controlled prosthetic knee. [2022]

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

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

7. Germany pubmed.ncbi.nlm.nih.gov

Developing a control framework for self-adjusting prosthetic sockets incorporating tissue injury risk estimation and generalized predictive control. [2022]

8. 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]

9. England pubmed.ncbi.nlm.nih.gov

Powered knee and ankle prostheses enable natural ambulation on level ground and stairs for individuals with bilateral above-knee amputation: a case study. [2023]

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

Strategies to reduce the configuration time for a powered knee and ankle prosthesis across multiple ambulation modes. [2022]

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

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

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

Powered Sit-to-Stand and Assistive Stand-to-Sit Framework for a Powered Transfemoral Prosthesis. [2021]