eOPRA Implant + Magnetic Bead Tracking for Amputation

(TTeOPRA+MB Trial)

Not currently recruiting at 1 trial location

Overseen By Hugh M Herr, PhD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Brigham and Women's Hospital

Must not be taking: Corticosteroids, Immunosuppressants, Chemotherapy

Disqualifiers: Diabetes, Osteoporosis, Peripheral vascular disease, others

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

Compensation: Varies

Number of Visits: 1

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a new implant system designed to improve prosthetic limb control for individuals with a lower leg amputation. The eOPRA Implant System uses implanted electrodes to enhance communication between the body and prosthetic, while the Magnetic Bead Tracking System tracks muscle movements in real-time. It is best suited for those with a transtibial amputation (below the knee) who can walk at different speeds. Participants should not have severe health conditions or active skin diseases that could interfere with the treatment. As an unphased trial, this study offers a unique opportunity to contribute to groundbreaking research and potentially benefit from innovative technology.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications. However, if you have been on corticosteroids, immune-suppressive therapy, or chemotherapy drugs in the last six months, you may not be eligible to participate.

What prior data suggests that the eOPRA Implant System and Magnetic Bead Tracking System are safe for transtibial amputees?

Research has shown that the eOPRA Implant System, used for higher leg amputations, has raised some safety concerns over time. One study found that although patients experienced better function, there were instances of deep infections and mechanical problems, particularly with longer use.

The Magnetic Bead Tracking System is newer, so less information is available. Early studies are investigating its safety. This system uses small magnets to track muscle movement, aiding in the control of a prosthetic limb. So far, this method appears safe, but more research is needed to fully understand any risks.

In summary, while the eOPRA Implant has some known risks, the Magnetic Bead Tracking System is still under study. Both are promising, but participants should be aware of possible complications. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the eOPRA Implant System and Magnetic Bead Tracking System because they offer a novel approach for transtibial amputees. Unlike traditional prosthetics, which rely on sockets, the eOPRA Implant System directly connects to the bone, potentially improving comfort and mobility. Additionally, the Magnetic Bead Tracking System provides advanced tracking of limb movement, which could enhance the precision and function of the prosthetic. Together, these innovations aim to provide a more natural and intuitive experience for amputees, setting them apart from current options.

What evidence suggests that the eOPRA Implant System and Magnetic Bead Tracking System could be effective for amputation?

A previous study demonstrated reliable results with the e-OPRA Implant System in over 100 patients with limb amputations, significantly improving their quality of life. Research indicates that this system connects directly to the bone, making prosthetic limbs feel more natural and comfortable. Studies have shown that patients using these implants reported better movement and satisfaction compared to traditional prosthetics.

The Magnetic Bead Tracking System is still new, but early findings suggest it can help control prosthetic limbs more effectively. This system uses small magnets to track muscle movements and send signals to a robotic prosthesis, potentially allowing for more precise and natural control over the limb. In this trial, both the e-OPRA Implant System and the Magnetic Bead Tracking System will be used together, promising better control and comfort for amputees with their prosthetic limbs. ^{1 2 3 4 6}

Who Is on the Research Team?

Hugh M Herr, PhD

Principal Investigator

Massachusetts Institute of Technology

Matthew J Carty, MD

Principal Investigator

Brigham and Women's Hospital

Are You a Good Fit for This Trial?

This trial is for transtibial amputees, meaning individuals who have had a leg amputation below the knee. Participants should be willing to undergo surgery to implant the e-OPRA and Magnetic Bead Tracking systems and commit to follow-up sessions over approximately 24 months.

Inclusion Criteria

I have enough muscle and soft tissue in the area needing surgery to heal properly.

I have or will get an e-OPRA implant after a below-knee amputation.

In the opinion of the investigator, normal cognitive function and absence of any physical limitations, addictive diseases or underlying medical conditions that may preclude the patient from being a good study candidate

Exclusion Criteria

I have an active skin condition on the limb being tested.

I have severe muscle loss or damaged tissue in my limb needing surgery.

Subjects with evidence of or a documented history of severe peripheral vascular disease, diabetes mellitus (type I or type II), skin diseases, neuropathy or neuropathic disease and severe phantom pain, or osteoporosis, such that, in the opinion of the investigator, will not allow the subject to be a good study candidate

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Surgery and Implantation

Participants undergo one or more surgeries for the implantation of the e-OPRA Implant System and Magnetic Bead Tracking System

1-2 weeks

1 visit (in-person)

Rehabilitation and Initial Testing

Participants begin rehabilitation and initial testing of the prosthetic system, including stability assessments and EMG control activities

3 months

Multiple visits (in-person)

Long-term Follow-up

Participants are monitored for device stability and effectiveness, including walking gait and balance assessments

24 months

Regular visits (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• eOPRA Implant System
• Magnetic Bead Tracking System

Trial Overview The study tests an advanced prosthetic limb system combining the e-OPRA Implant System with implanted electrodes for better control, and a Magnetic Bead Tracking System that measures muscle movement in real-time for improved prosthesis responsiveness.

How Is the Trial Designed?

Group I: eOPRA Implant System for Transtibial Amputees and Magnetic Bead Tracking System Experimental Treatment 1 Intervention

Implantation of e-OPRA Implant System and Magnetic Bead Tracking System in lower limb.

Who Is Running the Clinical Trial?

Brigham and Women's Hospital

Lead Sponsor

Trials

1,694

Recruited

14,790,000+

Massachusetts Institute of Technology (MIT)

Collaborator

Trials

2

Recruited

200+

Integrum

Industry Sponsor

Trials

8

Recruited

250+

Published Research Related to This Trial

The presence of unilateral and bilateral metal hip prostheses has a negligible effect on the accuracy of tracking electromagnetic transponders, with average vector displacements of less than 0.5 mm and 0.3 mm respectively.

At clinically relevant distances, the tracking error remains minimal, indicating that patients with hip prostheses can still be effectively monitored during treatments involving electromagnetic transponders.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of metal hip prosthesis on the accuracy of electromagnetic localization tracking. Bittner, N., Butler, WM., Kurko, BS., et al.[2022]

The endo-exo prosthesis (EEP) system has shown reliable outcomes in over 100 patients with limb amputations, significantly improving their quality of life and comfort compared to traditional socket prostheses.

Patients reported enhanced sensory feedback (osso-perception) and increased functionality, with the EEP technique now being applied successfully to various types of amputations, including above-knee, transtibial, and transhumeral.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[The endo-exo prosthesis treatment concept : Improvement in quality of life after limb amputation]. Hoffmeister, T., Schwarze, F., Aschoff, HH.[2022]

The study evaluated two types of percutaneous trans-femoral implants, the OPRA and ISP Endo/Exo prostheses, focusing on their effects on bone mechanics and failure risk during early and later stages of bone ingrowth.

While the ISP design provided better strain energy distribution for long-term bone health, the OPRA design reduced bone stress, lowering the risk of fractures; however, both designs showed a relatively low safety factor against mechanical failure, indicating a need for design improvements.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A comparative finite-element analysis of bone failure and load transfer of osseointegrated prostheses fixations. Tomaszewski, PK., Verdonschot, N., Bulstra, SK., et al.[2021]

The Osseointegrated Prostheses for the Rehabilitation of Amputees (OPRA) offers improved function and quality of life for patients with extremity amputations compared to traditional socket prosthetics, as demonstrated in clinical trials.

The OPRA implant has a long lifespan and a low complication rate, making it a promising option for enhancing rehabilitation in amputees.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Osseointegrated prostheses for the rehabilitation of amputees (OPRA): results and clinical perspective. Hoyt, BW., Walsh, SA., Forsberg, JA.[2020]

The study introduces a novel electromagnetic attachment system for prosthetic limbs, which could address common issues faced by amputees with traditional socket-based methods, potentially improving comfort and limb health.

Initial tests show that the electromagnetic system can effectively suspend a knee-ankle-foot prosthesis during walking, but further optimization is needed to manage heat generation during prolonged use.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Prosthetic Limb Attachment via Electromagnetic Attraction through a Closed Skin Envelope. Flanagan, W., Becraft, K., Warren, H., et al.[2023]

The osseointegrated implant system (OPRA) demonstrated stable fixation over a long-term period, with minimal migration and rotation of the implant observed in a study of 51 patients over 10 years.

Despite initial signs of bone cancellization around the implant in over half of the patients by the 2-year mark, this issue decreased by the 5-year follow-up, suggesting positive bone remodeling and stability of the OPRA system.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Stable fixation of an osseointegated implant system for above-the-knee amputees: titel RSA and radiographic evaluation of migration and bone remodeling in 55 cases. Nebergall, A., Bragdon, C., Antonellis, A., et al.[2022]

Osseointegrated prostheses provide significant advantages over traditional socket suspension methods, including better weight bearing, improved joint motion, and enhanced sensory feedback for amputees.

The OPRA program has developed specific surgical techniques and rehabilitation protocols for various types of amputations, showing promising long-term results for patients with transradial, transhumeral, and transfemoral amputations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Osseointegrated prostheses for rehabilitation following amputation : The pioneering Swedish model. Li, Y., Brånemark, R.[2022]

The novel Limb Prosthesis Osseointegrated Fixation System (LPOFS) shows better stress distribution in bone compared to traditional implants, which helps reduce stress shielding and overloading, making it a safer option for long-term use.

While the OPRA implant provides better initial anchoring, the LPOFS demonstrates superior resistance to extraction and maintains favorable stress distribution in cortical bone, indicating its potential for improved functionality in limb prosthesis attachment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Biomechanical evaluation of a novel Limb Prosthesis Osseointegrated Fixation System designed to combine the advantages of interference-fit and threaded solutions. Prochor, P., Piszczatowski, S., Sajewicz, E.[2017]

The Wireless Monitoring System of Orthopedic Implants (WMSoOI) is designed to wirelessly monitor the condition of orthopedic implants, detecting issues like abnormal wear and excessive force, which can help in early diagnosis and intervention.

The system includes a low power integrated circuit that has been tested for its RF communication capabilities, with future plans to integrate additional components like an Analog Digital Converter and Micro Control Unit for comprehensive monitoring.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Low power IC design of the Wireless Monitoring System of the Orthopedic Implants. Chen, H., Liu, M., Jia, C., et al.[2020]

Citations

1. clinicaltrials.gov clinicaltrials.gov/study/NCT07195461

Feasibility Study Evaluating the Safety and Effectiveness of ... This is an early feasibility study designed to provide preliminary evidence for the safety and effectiveness of the Magnetic Bead Tracking ...

2. withpower.com withpower.com/trial/early-phase-1-transtibial-amputees-8-2025-78f28

Magnetic Bead Tracking System for Below-Knee Amputees The study aims to gather initial safety and effectiveness data on using a Magnetic Bead Tracking System with a bionic external prosthesis.

3. clinicaltrials.gov clinicaltrials.gov/study/NCT06391697

Magnetic Bead Tracking System and eOPRA Implant ... The purpose of the study is to evaluate the feasibility of a transtibial amputee with the e-OPRA Implant System and Magnetic Bead Tracking System exhibiting ...

4. withpower.com withpower.com/trial/eopra-implant-magnetic-bead-tracking-for-amputation-c4bbb

eOPRA Implant + Magnetic Bead Tracking for Amputation ... The endo-exo prosthesis (EEP) system has shown reliable outcomes in over 100 patients with limb amputations, significantly improving their quality of life and ...

5. sciencedirect.com sciencedirect.com/science/article/pii/S2468451123000168

The myokinetic interface: Implanting permanent magnets to ... Here we report on the myokinetic interface concept that exploits magnetic field principles to achieve natural control and sensory feedback of an artificial ...

6. go.drugbank.com go.drugbank.com/conditions/DBCOND0029757

Amputations (DBCOND0029757) Magnetic Bead Tracking System and EOPRA Implant System with Bionic Prosthesis for Transtibial Amputees ... Outcome System for Individuals With Lower Limb ...