Powered Prosthesis for Amputation

Overseen By Suzanne Finucane, MS, PTA

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Shirley Ryan AbilityLab

Disqualifiers: Cognitive impairment, Visually impaired, Smoking, others

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

Approved in 2 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 20

6 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial evaluates the effectiveness of a powered prosthetic leg for individuals with an above-the-knee amputation who have undergone specific surgeries to enhance muscle and bone connection. It examines the prosthesis's impact on walking ability, control, and overall user satisfaction. Eligible participants should have an above-the-knee amputation and already use a regular prosthesis comfortably. This trial may suit those who have had or plan to have surgeries that connect the prosthetic directly to the bone and nerves, such as Perform Osseointegration (OI) surgery and Targeted Muscle Reinnervation (TMR). As an unphased trial, it provides a unique opportunity to explore innovative prosthetic solutions and improve quality of life.

Will I have to stop taking my current medications?

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

What prior data suggests that this powered prosthesis is safe for use with transfemoral osseointegration recipients?

Research has shown that combining osseointegration (OI) surgery with targeted muscle reinnervation (TMR) is generally safe. Participants who underwent both OI and TMR reported healthier limbs and increased use of their prosthetic limbs. They also found it easier to control their prosthetics.

For users of powered knee-ankle prosthetics, early results suggest enhanced movement and quality of life. Participants experienced improved function and expressed greater satisfaction with these advanced prosthetics. Overall, evidence supports that these treatments can significantly enhance mobility and daily life for amputees. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the powered prosthesis for amputees because it combines two advanced procedures: Osseointegration (OI) surgery and Targeted Muscle Reinnervation (TMR). Unlike traditional prosthetics that rely on sockets and external control, this approach integrates the prosthesis directly with the bone and nerves, offering more natural movement and control. This could lead to improved comfort, better mobility, and a seamless connection between the user's neural signals and the prosthetic limb. By evaluating these innovations, the trial aims to uncover significant improvements in quality of life and functionality for amputees.

What evidence suggests that this powered prosthesis is effective for improving mobility in individuals with above-knee amputation?

Research has shown that osseointegration (OI) surgery, which directly connects the prosthetic to the bone, offers a more stable fit for people with above-knee amputations. This stability can enhance movement and control of the prosthetic. Studies have found that targeted muscle reinnervation (TMR), a surgery that redirects nerves, improves control of the prosthetic limb and reduces pain, such as phantom limb pain. In this trial, participants will undergo both OI surgery and TMR, and researchers will evaluate their use of powered prosthetics. When combined with powered prosthetics, these surgeries allow for more natural and intuitive movement. Many patients have reported satisfaction with the improved control and quality of life. Overall, these treatments show promise in enhancing function and experience for those with above-knee amputations. ^{6 7 8 9 10}

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 aged 18-70 with an above-knee amputation who currently use a prosthesis and can safely operate it. They must be able to walk at various levels (K2/K3/K4), produce detectable muscle signals, and either are candidates for or have had osseointegration (OI) and targeted muscle reinnervation (TMR) surgeries.

Inclusion Criteria

I am a candidate for or have had orthopedic implant surgery.

Candidate for a myoelectric prosthesis (can generate mV level electromyographic EMG signals as detected by surface electrodes

I am a candidate for or have had TMR surgery as confirmed by my surgical team.

Exclusion Criteria

Significant comorbidity that would preclude completion of the study, use of prostheses, or would otherwise prevent data acquisition by researchers

I cannot have certain bone and nerve integration surgeries.

I understand and can follow the study's requirements.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Pre-Surgery Fitting and Training

Participants are fit for a custom instrumented socket and trained on using the powered prosthesis. EMG data are collected for pattern recognition control system training.

10-12 weeks

Up to 10 visits (in-person)

OI and TMR Surgery and Recovery

Participants undergo osseointegration and targeted muscle reinnervation surgeries, followed by recovery.

12 weeks

Post-Surgery Fitting and Training

Participants are fit with the powered prosthesis using the OI interface and trained on its use. Functional, metabolic, and biomechanical benefits are evaluated.

10-12 weeks

Up to 10 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment, including assessments of mobility, balance, and user satisfaction.

1 year

What Are the Treatments Tested in This Trial?

Interventions

• Perform Osseointegration (OI) surgery and Targeted Muscle Reinnervation (TMR)
• Powered Prosthesis Training and EMG data collection

Trial Overview The study tests how well people with above-knee amputations can move, control, and feel satisfied using a powered knee and ankle prosthesis after receiving OI and TMR surgeries. It involves training on the new prosthesis as well as collecting muscle activity data.

How Is the Trial Designed?

Group I: Evaluation of Powered Prosthesis for use with Transfemoral Osseointegration Recipients Experimental Treatment 2 Interventions

Perform Osseointegration (OI)Surgery and Targeted Muscle Reinnervation (TMR) and evaluate powered prosthesis training and use. The participant will complete non-weightbearing neural control tasks along with functional, biomechanical, metabolic and qualitative patient-reported outcome measures using the OI interface and the powered leg prosthesis.

Perform Osseointegration (OI) surgery and Targeted Muscle Reinnervation (TMR) is already approved in United States, European Union for the following indications:

Approved in United States as Osseointegration Limb Replacement for:

• Upper limb amputations
• Lower limb amputations
• Transtibial amputations
• Transhumeral amputations

Approved in European Union as Osseointegration Limb Replacement for:

• Upper limb amputations
• Lower limb amputations

Who Is Running the Clinical Trial?

Shirley Ryan AbilityLab

Lead Sponsor

Trials

212

Recruited

17,900+

Northwestern Memorial Hospital

Collaborator

Trials

42

Recruited

15,800+

Northwestern University

Collaborator

Trials

1,674

Recruited

989,000+

Published Research Related to This Trial

Targeted Muscle Reinnervation (TMR) enhances control of myoelectric prostheses for above-elbow amputees by allowing for more independent muscle signal activation through nerve re-routing, but it requires careful patient selection and a specific rehabilitation protocol.

The rehabilitation protocol includes pre-surgery assessments and post-surgery interventions focusing on pain control, muscle training, and functional assessments, ensuring effective integration of the prosthesis and optimizing patient outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Therapy Interventions for Upper Limb Amputees Undergoing Selective Nerve Transfers. Sturma, A., Hruby, LA., Boesendorfer, A., et al.[2022]

Targeted muscle reinnervation (TMR) is effective in reducing phantom limb pain (PLP) and residual limb pain (RLP) in lower extremity amputees, based on a systematic review of 11 studies involving 318 patients.

The procedure has a low complication rate, with postoperative neuroma being the most common issue reported in only 7.2% of cases, indicating that TMR is a safe option for managing pain after amputation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The application of targeted muscle reinnervation in lower extremity amputations: A systematic review. Berger, LE., Shin, S., Haffner, ZK., et al.[2023]

Targeted muscle reinnervation (TMR) surgery enhances the control of intelligent prosthetics by reconstructing the neural pathways that connect the brain to the muscles, allowing for more intuitive movement in amputees.

TMR has been recognized internationally as a groundbreaking approach to improve prosthetic function, and it holds the potential to significantly benefit the estimated 2 million amputees in China by providing a new standard of care.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Targeted muscle reinnervation: a surgical technique of human-machine interface for intelligent prosthesis]. Guo, Y., Zhao, W., Huang, J., et al.[2023]

Targeted muscle reinnervation (TMR) allows patients with upper-limb amputations to control prosthetic arms using EMG signals from reinnervated muscles, demonstrating a high success rate of 96.3% for elbow and wrist movements.

Patients who underwent TMR surgery were able to perform various arm movements with a virtual prosthetic arm, showing that reinnervated muscles can effectively provide the necessary neural control for advanced prosthetic devices.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Targeted muscle reinnervation for real-time myoelectric control of multifunction artificial arms. Kuiken, TA., Li, G., Lock, BA., et al.[2022]

Targeted muscle reinnervation (TMR) successfully increased the number of EMG signals available for controlling myoelectric prostheses in seven patients, enhancing their ability to perform movements from an average of 1-2 signals pre-surgery to 3-5 signals post-surgery.

Post-TMR, six out of seven patients achieved six degrees of freedom in prosthesis control without needing co-contraction to switch functions, indicating a significant improvement in intuitive control and functionality with no major surgical complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Targeted muscle reinnervation to improve electromyography signals for advanced myoelectric prosthetic limbs: a series of seven patients. Myers, H., Lu, D., Gray, SJ., et al.[2021]

Targeted muscle reinnervation (TMR) can significantly improve the control of myoelectric prostheses for amputees, but its application is still limited for lower extremity amputations and neuroma reconstruction.

A systematic review of 17 studies has identified common trends in nerve transfers and target muscle selections for TMR, which can aid in simplifying surgical decision-making and enhance the integration of TMR into reconstructive care.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Demystifying Targeted Muscle Reinnervation: A Systematic Review of Nerve Transfers for the Lower Extremity. Henderson, JT., Koenig, ZA., Climov, M., et al.[2023]

The study identified the locations and number of motor end plates for key muscles used in targeted muscle reinnervation (TMR) in the upper arm, based on dissections of 18 cadaver limbs, which can enhance prosthetic control for amputees.

Reliable anatomical landmarks were established for the medial biceps, brachialis, and lateral triceps, which can help surgeons accurately locate nerve branches during TMR procedures, potentially improving surgical outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Targeted Muscle Reinnervation of the Brachium: An Anatomic Study of Musculocutaneous and Radial Nerve Motor Points Relative to Proximal Landmarks. Renninger, CH., Rocchi, VJ., Kroonen, LT.[2022]

Combining targeted muscle reinnervation (TMR) with regenerative peripheral nerve interface (RPNI) techniques (TMRpni) in a patient with a left above-the-knee amputation resulted in reduced phantom and nerve pain.

This innovative approach may enhance the quality of life for amputee patients as the technique gains wider acceptance and understanding in clinical practice.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Combined TMR and RPNI in a vasculopathy patient: A case report. Galbraith, LG., Najafali, D., Gatherwright, JR.[2023]

Citations

1. youtube.com youtube.com/watch?v=nuN9BPqEGTo

Osseointegration Limb Replacement Surgery for Transfemoral ... Dr. S. Robert Rozbruch describes the technique of Osseointegration Limb Replacement Surgery for transfemoral amputation.

2. withpower.com withpower.com/trial/phase-amputations-2024-d0ff2

Powered Prosthesis for Amputation Trial Overview The study tests how well people with above-knee amputations can move, control, and feel satisfied using a powered knee and ankle prosthesis after ...

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC11943540/

Breaking Barriers—The Promise and Challenges of Limb ... Osseointegration surgery, a promising alternative, offers the direct skeletal attachment of bone, implant, and prosthetic, providing a more stable and ...

4. sciencedirect.com sciencedirect.com/science/article/abs/pii/S1878875020318131

Targeted Muscle Reinnervation and Osseointegration for ... TMR is a peripheral nerve surgical procedure proposed to improve the intuitive control of the prosthetic arm and for neuroma and phantom pain management.

5. sralab.org sralab.org/research/labs/bionic-medicine/projects/osseointegration-powered-legs

Osseointegration for Powered Leg Prostheses The objective of this study is to evaluate the movement of individuals with leg amputation who have received OI and TMR and are using a fully powered ...

6. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/40439344/

Outcomes in transhumeral upper limb amputation with ... Cases with OI and TMR reported better residual limb health, greater intuitiveness, and more hours of daily prosthesis use than controls.

7. onlinelibrary.wiley.com onlinelibrary.wiley.com/doi/abs/10.1002/pmrj.13407

Outcomes in transhumeral upper limb amputation with ... Cases with OI and TMR reported better residual limb health, greater intuitiveness, and more hours of daily prosthesis use than controls.

8. sciencedirect.com sciencedirect.com/science/article/pii/S2666769X2300009X

Osseointegration for amputees: Current state of direct ... Compelling evidence now demonstrates consistent and significant improvements in patient reported outcomes and quality of life as well as functional outcome ...

9. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC12081100/

Targeted Muscle Reinnervation—an Up-to-Date Review This article provides a current review of the various indications for TMR and surgical techniques, organized by amputation site, timing, and regional anatomy.

10. sciencedirect.com sciencedirect.com/science/article/pii/S2949912725001023

A Critical Review and Synthesis of Patient Selection Criteria The 17 articles included in this review described characteristics and outcomes of a total of 1,423 patients obtaining OI following limb ...