NCT07615465

Brief Summary

The purpose of the study is to investigate the clinical and functional outcomes of a transfemoral amputation with osseointegrated titanium implant, AMI muscle constructs, and implanted electrodes in the domain of gait, free space control, and embodiment.

Trial Health

55
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
2

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Apr 2017

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
active not recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

April 15, 2017

Completed
8.3 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

July 18, 2025

Completed
3 months until next milestone

First Submitted

Initial submission to the registry

October 10, 2025

Completed
8 months until next milestone

First Posted

Study publicly available on registry

May 29, 2026

Completed
2 months until next milestone

Study Completion

Last participant's last visit for all outcomes

July 17, 2026

Completed
Last Updated

May 29, 2026

Status Verified

May 1, 2026

Enrollment Period

8.3 years

First QC Date

October 10, 2025

Last Update Submit

May 22, 2026

Conditions

Outcome Measures

Primary Outcomes (6)

  • Kinematic Measures of Lower-Limb Biomechanics

    Quantitative analysis of joint angles, during level-ground walking, stair negotiation, and other functional tasks. Outcomes will be assessed using a motion capture system (e.g., Vicon) and embedded prosthesis sensors.

    An average of 2 sessions in the span of 1 week

  • Spatiotemporal Gait Parameters

    Evaluation of stance-to-swing ratio during ambulation. Parameters will be obtained using a motion capture system (e.g., Vicon) and an instrumented walkway. Data will be analyzed to assess functional walking ability and compared to normative or baseline values.

    An average of 2 sessions in the span of 1 week

  • Assessment of Patient Ability to Control each Joint of the Prosthesis

    Assessment of volitional control of the powered knee and ankle joints via neural signals from the residual limb. Participants will perform isolated joint control trials in seated positions. Outcomes include joint command accuracy evaluated using surface electromyography (EMG) and motion capture. These measures will quantify the participant's ability to intentionally control each prosthetic joint.

    An average of 2 sessions in the span of 1 week

  • Ground Reaction Forces

    Quantitative analysis of ground reaction forces during level-ground walking, stair negotiation, and other functional tasks. Outcomes will be assessed using instrumented force plates.

    An average of 2 sessions in the span of 1 week

  • Joint Torques

    Quantitative analysis of joint torques during level-ground walking, stair negotiation, and other functional tasks. Outcomes will be assessed using a motion capture system (e.g., Vicon), instrumented force plates, and embedded prosthesis sensors.

    An average of 2 sessions in the span of 1 week

  • Walking speed

    Evaluation of walking speed during ambulation. Parameters will be obtained using a motion capture system (e.g., Vicon) and an instrumented walkway. Data will be analyzed to assess functional walking ability and compared to normative or baseline values.

    An average of 2 sessions in the span of 1 week

Study Arms (1)

Osseointegration surgery

EXPERIMENTAL

Transfemoral amputation with osseointegrated titanium implant, AMI muscle constructs, and implanted electrodes

Device: MIT Powered Knee Prosthesis

Interventions

MIT powered knee prosthesis developed by the MIT Biomechatronics Group.

Osseointegration surgery

Eligibility Criteria

Age22 Years - 65 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Male or Female age 22-65 at the time of surgery.
  • The patient must have a medical condition requiring performance of a unilateral transfemoral amputation with a minimum of 13 cm of residual femur after amputation, and: A. At a minimum level of amputation of 20 cm or greater above the knee joint line if physical therapy and prosthetist evaluation is commensurate with a standard K3 ambulatory status; or, B. At a minimum level of amputation of 16 cm above the knee joint line as part of a single- stage procedure if physical therapy and prosthetist evaluation is commensurate with a more active K3 or less active K4 postoperative ambulatory status.
  • The subject must have undergone independent consultation with at least two lower extremity surgical specialists to ensure they have exhausted all limb salvage options prior to undergoing amputation, as well as a psychiatric evaluation to ensure appropriate capacity and volition.
  • The patient must have the ability to ambulate at variable cadence (an expected lower extremity prosthesis functional level of K3 or above).
  • The patient must have adequate bone stock to support the implanted device.
  • In the opinion of the investigators, normal cognitive function and absence of any physical limitations, addictive diseases or underlying medical conditions that may preclude patient from being a good surgical and/or study candidate.
  • Willingness, ability and commitment to participate in baseline and follow-up evaluations for the full length of the study including the prescribed rehabilitation program.
  • Written informed consent to participate in the study provided by the patient or legal representative.

You may not qualify if:

  • Women who are pregnant, lactating or planning a pregnancy during the first twelve (12) months of the post-surgical follow- up.
  • Subjects who have not been completely abstinent from tobacco use for at least 6 weeks preoperatively.
  • Active infection or dormant bacteria.
  • Subjects would have less than 2 mm of remaining cortex bone available around the implant, if implanted.
  • 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.
  • Evidence of any active skin disease involving the proposed surgical limb.
  • History of systemically administered corticosteroids, immune- suppressive therapy or chemotherapy drugs within six (6) months of implant surgery.
  • Severe co morbidity, atypical skeletal anatomy, or poor general physical/mental health that, in the opinion of the Investigator, will not allow the subject to be a good study candidate (i.e. other disease processes, mental capacity, substance abuse, shortened life expectancy, vulnerable patient population, BMI \>40, etc.).
  • The patient is currently involved in another clinical study where that participation may conflict or interfere with the treatment, follow-up or results of this clinical study.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

MIT Media Lab

Cambridge, Massachusetts, 02139, United States

Location

Study Officials

  • Hugh Herr, PhD

    Massachusetts Institute of Technology

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

October 10, 2025

First Posted

May 29, 2026

Study Start

April 15, 2017

Primary Completion

July 18, 2025

Study Completion

July 17, 2026

Last Updated

May 29, 2026

Record last verified: 2026-05

Data Sharing

IPD Sharing
Will not share

Individual participant data (IPD) will not be shared. This study involves a small cohort and a particular surgical procedure. Even with direct identifiers removed, the combination of clinical timelines and outcomes could increase the risk of re-identification. Summary/aggregate results (and selected analyses) have been reported in a peer-reviewed publication.

Locations