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NCT Number: NCT04063592

AMI Construction in Lower Extremity Residual Limbs

This study will involve the development of a novel approach to lower extremity residual limb surgical revision that offers the promise of augmenting volitional motor control, restore proprioception and reverse atrophy

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Key information

Conditions

Amputation Nervous System Diseases Neurobehavioral Manifestations Neurologic Manifestations Pain Pain, Postoperative Pathologic Processes Pathological Conditions, Signs and Symptoms Perceptual Disorders Phantom Limb Postoperative Complications Signs and Symptoms

Age range

18 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Walter Reed National Military Medical Center, Bethesda, Maryland, United States

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About this study

The hypothesis of this research protocol is that we will be able to modify the residual limbs of patients who have already undergone lower extremity amputations so as to include biological actuators that will enable the successful employment of next generation lower extremity prostheses, diminish/eliminate phantom limb pain, restore proprioception and regenerate lost muscle mass. The specific aims of the project are as follows:

  • To develop a standardized operative technique for both above knee (AK) and below knee (BK) amputation revision procedures that includes AMIs to restore musculotendinous proprioceptive capabilities
  • To assess the capacity for these actuators to provide enhanced motor control and sensory feedback, as well as ablate phantom limb symptomatology and augment residual limb muscle mass
  • To determine the reinnervation time course and longevity of these biological constructs
  • To validate the functional and somatosensory superiority of the proposed revision technique over standard approaches to BKA and AKA
  • To develop a modified acute postoperative rehabilitation strategy suited to this new surgical approach

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Between the ages of 18-65
  • Has already undergone a standard AKA or BKA procedure
  • Suffers from symptoms such as:
  • Intractable pain
  • Deterioration of skin on or around stump
  • Suffering from other sources of discomfort arising from stump
  • Intact inherent wound healing
  • Adequate communication skills
  • High motivation

Exclusion criteria

  • Inadequate health to undergo operative procedure using standard anesthesia (i.e. cardiopulmonary)
  • Individuals with impaired wound healing
  • Individuals suffering from extensive peripheral neuropathies
  • Active smokers
  • Individuals with a history of poor compliance
  • Women who are pregnant or plan to become pregnant before surgical intervention

Treatment and study plan

Residual limb revision

Procedure

Surgical procedure involving construction of agonist-antagonist myoneural interfaces (AMIs)

Primary outcomes

  1. Limb Morphology and Changes in Muscle Volume

    Time frame: Years 1-3

    Clinical examination and images from CT/MRI will be combined to construct a holistic view of the morphology of the residual limb. Imaging studies and limb measurements taken in clinic will also be used to measure muscle atrophy/hypertrophy over time.

  2. Degree of Motor Activation of AMI Muscles and Volitional Control of Phantom Limb

    Time frame: Years 1-3

    Clinical examination will confirm the sliding motion of the AMI constructs with radiologic evaluation measuring the length of muscle excursion through each construct. Functional testing and testing using a prosthesis will determine how well a patient is able to volitionally control the AMI muscles.

  3. Evidence of Proprioception

    Time frame: Years 1-3

    Subjective reporting combined with tests run using a prosthesis will indicate if proprioception is still intact after surgery. Results will be confirmed by monitoring brain activity during limb movement activities via fMRI.

  4. Evidence of Sensory Perception

    Time frame: Years 1-3

    Subjective reporting and clinical tests of Semmes-Weinstein and two-point discrimination will determine if the patient has sensory perception on the residual limb.

  5. General Health

    Time frame: Years 1-3

    Patient-reported outcomes metrics from five validated tests (SIP136, EQ-5D, SF-36, LEFS, PROMIS) will be combined to create an overall picture of patients' general health during and after their recovery.

  6. Complications

    Time frame: Years 1-3

    Delayed wound healing, infection, need for additional surgery, PE/DVT, death

Study contacts

Contact information is provided by the study sponsor or research team.

Matthew J Carty, MD

CONTACT

[email protected]

6179834555

Research Coordinators

CONTACT

[email protected]

Sponsors and collaborators

Lead sponsor

Brigham and Women's Hospital

Other

Collaborators

  • Massachusetts Institute of Technology

Registry information

Official study title

A Novel Approach to Lower Extremity Residual Limb Revision to Augment Volitional Motor Control, Restore Proprioception and Reverse Limb Atrophy

Important dates

Study start
2020
Primary completion
2026
Study completion
2026
First posted
Aug 21, 2019
Registry last updated
Jul 9, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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