eOPRA Implant + Magnetic Bead Tracking for Amputation

(TTeOPRA+MB Trial)

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

7 Participants Needed

Trial Summary

What is the purpose of this trial?

The e-OPRA Implant System, is a further development of the OPRA (Osseointegrated Prostheses for the Rehabilitation of Amputees) Implant System. The e-OPRA Implant system is an implant system for direct skeletal anchorage of amputation prostheses. The added feature in the e-OPRA Implant system, is a bidirectional interface into the human body that allows permanent and reliable communication using implanted electrodes. These electrodes will provide long-term stable bioelectric signals for an improved control of the prosthetic limb. The Magnetic Bead Tracking System, which will be implanted and used in combination with the e-OPRA Implant system, is an investigational device that consists of pairs of magnetic beads, and a set of magnetic field sensors that measure and track the length of muscles and the speed at which they move in real-time. When the beads are implanted in muscle in the residual limb of an amputee, the muscle length signal is communicated to an investigational, robotic ankle-foot prosthesis. 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 full neural control over a neuro-mechanical prosthetic system. A maximum of seven subjects will be enrolled. Each subject will undergo one or more surgeries where the e-OPRA Implant System and Magnetic Bead Tracking System will be implanted. The subjects will participate in follow-up sessions the last of which occurs approximately 24 months after the surgery. This is a prospective, non-randomized, uncontrolled study.

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 data supports the effectiveness of the eOPRA Implant System and Magnetic Bead Tracking System treatment for amputation?

Research on the OPRA Implant System, which is similar to the eOPRA Implant System, shows that it can improve the function and quality of life for amputees by providing better control and comfort compared to traditional socket prosthetics. Studies have demonstrated benefits in patient movement, prosthetic use, and overall well-being, with a long life-span and low complication rates. ^{1 2 3 4 5}

Is the eOPRA Implant System safe for humans?

The OPRA implant system, which is similar to the eOPRA Implant System, has been shown to be effective with a long lifespan and a low complication rate in clinical trials. It is designed to improve function and quality of life for amputees, with studies indicating a low risk of bone fracture and mechanical failure. ^{1 2 3 6 7}

How is the eOPRA Implant System with Magnetic Bead Tracking different from other treatments for amputations?

The eOPRA Implant System with Magnetic Bead Tracking is unique because it uses osseointegration (direct bone attachment) to secure the prosthetic, which can improve comfort and control compared to traditional socket prosthetics. Additionally, the Magnetic Bead Tracking System may offer enhanced monitoring and tracking of the prosthetic's position and movement, potentially improving the overall functionality and user experience. ^{2 3 5 8 9}

Research Team

Hugh M Herr, PhD

Principal Investigator

Massachusetts Institute of Technology

Matthew J Carty, MD

Principal Investigator

Brigham and Women's Hospital

Eligibility Criteria

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.

I am between 22 and 65 years old.

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

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)

Treatment Details

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.

Participant Groups

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+

Findings from Research

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 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 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]

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 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 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 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 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]

References

1. Germany pubmed.ncbi.nlm.nih.gov

Osseointegrated prostheses for rehabilitation following amputation : The pioneering Swedish model. [2022]

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

Osseointegrated prostheses for the rehabilitation of amputees (OPRA): results and clinical perspective. [2020]

3. Sweden 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. [2022]

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

Prosthetic Limb Attachment via Electromagnetic Attraction through a Closed Skin Envelope. [2023]

5. Germany pubmed.ncbi.nlm.nih.gov

[The endo-exo prosthesis treatment concept : Improvement in quality of life after limb amputation]. [2022]

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

A comparative finite-element analysis of bone failure and load transfer of osseointegrated prostheses fixations. [2021]

7. Poland 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. [2017]

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

Effect of metal hip prosthesis on the accuracy of electromagnetic localization tracking. [2022]

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

Low power IC design of the Wireless Monitoring System of the Orthopedic Implants. [2020]