Fast Electrode for Hand Amputation

Overseen By Debby Noble

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Texas Southwestern Medical Center

Disqualifiers: Nerve dysfunction, Cardiac arrhythmia, others

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

Compensation: Varies

Number of Visits: 12

25 Participants Needed

Trial Summary

What is the purpose of this trial?

Our goal is to temporarily implant the following groups for 540 +/- 30 days: 1. Forearm FAST electrodes 1. Five human partial hand amputees (amputated at the level of the hand) with 2 FAST electrodes in the ulnar nerve and 2-5 FAST electrodes in the median nerve. 2. Five human hand and forearm amputees (amputated at the level of the forearm) with 2 FAST electrodes in the ulnar nerve and 2-5 FAST electrodes in the median nerve . 2. Arm FAST electrodes 1. Five human partial hand amputees (amputated at the level of the hand) with 2 FAST electrodes in the ulnar nerve and 2-5 FAST electrodes in the median nerve. 2. Five human hand and forearm amputees (amputated at the level of the forearm) with 2 FAST electrodes in the ulnar nerve and 2-5 FAST electrodes in the median nerve. 3. Five human hand, forearm and arm amputees (amputated at the level of the arm) with 2 FAST electrodes in the ulnar nerve and 2-5 FAST electrodes in the median nerve.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What data supports the effectiveness of the treatment DEFT, DExterous Hand Control Through Fascicular Targeting, for hand amputation?

The FAST-LIFE approach, which is part of the DEFT treatment, has shown effectiveness in providing control over a robotic hand and restoring sensory feedback in upper-limb amputees by targeting specific nerve areas. Additionally, a bioelectric neural interface using similar technology demonstrated high accuracy control of a prosthetic hand, suggesting that DEFT could offer precise and intuitive control for amputees. ^{1 2 3 4 5}

Is the Fast Electrode for Hand Amputation generally safe for humans?

The Fast Electrode for Hand Amputation, using the FAST-LIFE approach, has been tested in clinical studies with 6 human amputees, showing it can be safely used for motor and sensory restoration in upper-limb amputees. ^{1 6 7 8 9}

How does the DEFT treatment differ from other treatments for hand amputation?

The DEFT treatment is unique because it uses a specialized approach called FAST (Fascicle-Specific Targeting) with LIFE (Longitudinal Intrafascicular Electrodes) to directly interface with the nerves in the residual limb, allowing for precise control of a prosthetic hand and restoration of sensory feedback. This method provides a more natural and intuitive control compared to traditional prosthetics, which often rely on surface muscle signals and lack detailed sensory feedback. ^{1 2 5 10 11}

Research Team

Jonathan Cheng, MD

Principal Investigator

UT Southwestern Medical Center

Eligibility Criteria

This trial is for adults who have had a hand, forearm, or arm amputation and can manage their pain well. Participants must be able to sign consent, take part in all study activities including device implantation and removal, and communicate effectively in English without an interpreter.

Inclusion Criteria

I am an adult with an amputation of my hand, forearm, or arm.

Able and willing to sign Consent

Able to communicate effectively in English without an interpreter

Exclusion Criteria

My tests show nerve or muscle issues not matching my amputation stump's look.

I have a history of irregular heartbeats.

Radiographs confirm unsuitability of the amputation stump configuration

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Pre-operative

Pre-operative imaging and diagnostic studies including MRI, x-ray, EMG/Nerve conduction studies, and psychological assessment

Up to 30 days before surgery

Implantation Surgery

Surgery to implant FAST electrodes in the ulnar and median nerves, followed by immediate post-operative care

1 week

Hospital stay up to 2 nights

Post-operative Care

Weekly outpatient care for 3 weeks following implantation surgery, including inspection and dressing changes of electrode leads

3 weeks

Weekly visits (in-person)

Experimental Data Collection

Human physiology experiments including motor and sensory assessments, conducted up to 6 times per month

540 +/- 30 days

Up to 6 visits per month

Explantation Surgery

Surgery to remove implanted electrodes, followed by post-operative care

1 week

1 visit (in-person) post-surgery

Follow-up

Participants are monitored for safety and effectiveness after explantation

3 weeks

2 visits (in-person)

Treatment Details

Interventions

• DEFT

Trial Overview The DEFT trial is testing 'FAST electrodes' implanted for about 540 days in the nerves of people with different levels of limb amputation. The goal is to improve control over prosthetic hands through advanced nerve targeting.

Participant Groups

Group I: Fast electrodes Experimental Treatment 1 Intervention

Implant temporary Fast electrodes and record the nerve signals that control delicate finger motions and play back the nerve signals that give the hand feelings of touch and movement.

Who Is Running the Clinical Trial?

University of Texas Southwestern Medical Center

Lead Sponsor

Trials

1,102

Recruited

1,077,000+

Defense Advanced Research Projects Agency

Collaborator

Trials

19

Recruited

78,900+

University of Minnesota

Collaborator

Trials

1,459

Recruited

1,623,000+

Arizona State University

Collaborator

Trials

311

Recruited

109,000+

Nerves Incorporated, Inc.

Collaborator

Trials

1

Recruited

30+

Findings from Research

The FAST-LIFE approach, which uses multichannel longitudinal intrafascicular electrodes, allows for precise targeting of sensory and motor fascicles in amputated limbs, enabling better control of robotic hands and restoration of sensory feedback.

In clinical studies involving 6 human amputees, this method demonstrated the ability to discern motor intent for individual finger movements, highlighting its potential for improving prosthetic functionality.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Fascicle-Specific Targeting of Longitudinal Intrafascicular Electrodes for Motor and Sensory Restoration in Upper-Limb Amputees. Cheng, J., Yang, Z., Overstreet, CK., et al.[2021]

Transplanting a toe to the forearm amputation stump allows for direct control of a specially designed multidimensional electronic prosthetic hand, significantly improving functionality.

After rehabilitation, the prosthetic hand achieved a 100% correct recognition rate when controlled by the transplanted toe, demonstrating a highly effective method for restoring hand function.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A reconstructed digit by transplantation of a second toe for control of an electromechanical prosthetic hand. Chen, ZW., Hu, TP.[2022]

This case study introduces a novel targeted sensory reinnervation technique that successfully restored sensory function in a transhumeral amputee by rerouting specific nerve fascicles to cutaneous nerves, allowing for distinct hand maps of sensation.

The subject was able to control a robotic arm while receiving touch and force feedback, demonstrating the first successful dual flow of motor and sensory information in a prosthetic limb, which is a significant step towards creating more natural and functional prosthetic devices.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Novel targeted sensory reinnervation technique to restore functional hand sensation after transhumeral amputation. Hebert, JS., Olson, JL., Morhart, MJ., et al.[2014]

Targeted muscle reinnervation (TMR) allows high-level amputees to control myoelectric prostheses more effectively, and using a generically placed electrode grid can enhance performance.

In a study with two transhumeral amputee subjects, the grid electrode layout resulted in faster action completion (0.290 to 1 second quicker) and lower classification error (1.35% vs. 3.2%) compared to traditional localized electrode placements, suggesting improved control and easier fitting for prostheses.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Performance of pattern recognition myoelectric control using a generic electrode grid with targeted muscle reinnervation patients. Tkach, DC., Young, AJ., Smith, LH., et al.[2020]

A new technology platform combining bioelectronics and AI allows for high-accuracy control of prosthetic hands, enabling up to 15 degrees of freedom in movement, which is a significant improvement for amputees.

The system uses a neural interface that decodes motor intention from peripheral nerves, providing an intuitive way for users to control their prosthetic hands, making it feel more natural and effective in daily activities.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A bioelectric neural interface towards intuitive prosthetic control for amputees. Nguyen, AT., Xu, J., Jiang, M., et al.[2022]

Partial hand amputations are common, with an incidence of about 1 in 18,000 people in western countries, yet treatment options have not significantly advanced due to challenges like anatomical variability and the complexity of restoring motor and sensory functions.

Current solutions for partial hand amputations often depend on skilled technicians for fitting rather than modern engineering techniques, highlighting a need for innovative approaches to improve treatment outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Treatment of the Partial Hand Amputation: An Engineering Perspective. Imbinto, I., Peccia, C., Controzzi, M., et al.[2022]

Longitudinally implanted intrafascicular electrodes (LIFEs) demonstrated excellent biocompatibility in a rabbit sciatic nerve model, showing stable signal recording capabilities over a six-month period with only mild tissue damage observed.

In a human test, LIFEs successfully recorded distinct signals from the radial, ulnar, and median nerves during voluntary hand movements, which could be utilized to control an electronic prosthetic hand, indicating their potential for advanced prosthetic applications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Experimental study of biocompatibility of LIFEs in peripheral fascicles]. Zheng, XJ., Zhang, J., Chen, ZW., et al.[2006]

A novel electrode design, called the transverse intrafascicular multichannel nerve electrode (TIME), shows promise in selectively activating small nerve fibers, which could help alleviate phantom limb pain (PLP) in amputees.

Preliminary studies in small and large animal models demonstrated good biocompatibility and stability of the implant, paving the way for future human clinical trials to explore its effectiveness in treating PLP.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Development of a neurotechnological system for relieving phantom limb pain using transverse intrafascicular electrodes (TIME). Stieglitz, T., Boretius, T., Navarro, X., et al.[2013]

The Revolutionizing Prosthetics program, initiated by the Defense Advanced Research Projects Agency in 2006, has led to significant advancements in upper extremity prosthetics, including the potential for direct brain-wave control of prosthetic limbs with 22 degrees of freedom.

Recent innovations, such as individually powered digits, have improved the functionality of prosthetic hands, but restoring sensory feedback remains a critical challenge for enhancing user integration and self-image.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Advances in upper extremity prosthetics. Zlotolow, DA., Kozin, SH.[2022]

The new soft neuroprosthetic hand is lightweight (292 g) and low-cost, providing myoelectric control and tactile feedback, which is a significant improvement over traditional heavy and expensive prosthetics.

In tests with individuals who have transradial amputations, this neuroprosthetic hand demonstrated better speed and dexterity compared to conventional rigid designs, allowing one user to regain a sense of touch and control in real-time.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A soft neuroprosthetic hand providing simultaneous myoelectric control and tactile feedback. Gu, G., Zhang, N., Xu, H., et al.[2023]

Developing better control interfaces for electric-powered prostheses, such as using cineplasties to connect muscles to prosthetic components, can significantly enhance user control and sensory feedback.

Tracking studies showed that individuals with biceps muscle tunnel cineplasties had improved control capabilities, demonstrating the efficacy of this approach compared to traditional control methods.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cineplasty as a control input for externally powered prosthetic components. Weir, RF., Heckathorne, CW., Childress, DS.[2006]

References

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

Fascicle-Specific Targeting of Longitudinal Intrafascicular Electrodes for Motor and Sensory Restoration in Upper-Limb Amputees. [2021]

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

A reconstructed digit by transplantation of a second toe for control of an electromechanical prosthetic hand. [2022]

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

Novel targeted sensory reinnervation technique to restore functional hand sensation after transhumeral amputation. [2014]

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

Performance of pattern recognition myoelectric control using a generic electrode grid with targeted muscle reinnervation patients. [2020]

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

A bioelectric neural interface towards intuitive prosthetic control for amputees. [2022]

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

Treatment of the Partial Hand Amputation: An Engineering Perspective. [2022]

7. China pubmed.ncbi.nlm.nih.gov

[Experimental study of biocompatibility of LIFEs in peripheral fascicles]. [2006]

8. Germany pubmed.ncbi.nlm.nih.gov

Development of a neurotechnological system for relieving phantom limb pain using transverse intrafascicular electrodes (TIME). [2013]

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

Advances in upper extremity prosthetics. [2022]

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

A soft neuroprosthetic hand providing simultaneous myoelectric control and tactile feedback. [2023]

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

Cineplasty as a control input for externally powered prosthetic components. [2006]