Clinical trial NCT06452186: Restoration of Normative Postural Control
Official title: Toward Restoration of Normative Postural Control and Stability Using Neural Control of Powered Prosthetic Ankles
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Lower Limb Amputation Below Knee (Injury)
Keywords: powered ankle prosthesis
direct EMG control
balance
cognitive load
muscle synergy
Lead sponsor: North Carolina State University
Sponsor class: OTHER
Collaborators: name: University of North Carolina, Chapel Hill
First posted: 2024-06-11
Enrollment: 50
Sex: ALL
Minimum age (years): 18
Maximum age (years): 99
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Two groups amputees go through the same training procedure with different prostheses. Their functionality will be compared before and the after the training.
Primary purpose: HEALTH_SERVICES_RESEARCH

Brief summary: The objective of this proposal is to investigate the effects of training to use direct electromyographic (dEMG) control of a powered prosthetic ankle on transtibial amputees'.

The aimed questions to answer:

1. whether dEMG control will improve balance and postural stability of amputees,
2. whether dEMG control will lead to more natural neuromuscular control and coordination, 3) whether dEMG control will reduce cognitive processes.

Participants will go through PT guided training on using dEMG controlled prosthetic ankles and are evaluated for their capability on functional tasks.

The results will be compared with a comparison group, which goes through the same training but with their everyday passive prostheses on balance capability, neuromuscular coordination, and cognitive load during locomotion.

Detailed description: Lab Visit Experience for Participants with lower limb amputation:

* Number of Lab Visits: 15 visits. Clinicians may recommend skipping some of the visits or tasks based on clinical evaluation and status of the participants.
* Length of Lab Visit: three hours maximum

  1. First visit: the purpose of the first visit is to conduct consent and conduct measurements to decide walking speed and ABC (amputee balance confidence) score.
  2. Second visit: this visit is to ensure that the amputees' own socket system can be integrated into the powered prosthetic leg and validate the effectiveness of the EMG interface.
  3. Third and fourth visits: baseline evaluation with powered prosthesis and passive prosthesis. Each participant will finish the two visits. One of the visits is dedicated to their own passive prosthesis and the other visit is for the powered prosthesis. The sequence of the evaluation is randomized. The tasks conducted in the two visits are generally identical. The only difference is that one of the visits uses the participants' everyday prosthetic foot and the other uses the powered prosthetic ankle
  4. Fifth and sixth visits: these visits are dedicated to have the participants trained to regain muscle coordination, which is critical to use the powered prosthetic ankle. All the participants will go through these trainings. Based on whether the participants are selected as the powered prosthetic group (Group A) or the passive group (Group B), the participants will finish this training with the powered prosthetic leg or a passive prosthetic leg.
  5. Seven - eleventh visits: These visits are designed to give participants needed training, so participants are able to integrate the action of the powered prosthetic ankle with their full body motion for various tasks. To ensure that contribution of the training procedure to the performance changes are considered, all the participants will go through the training with the prostheses aligned with their group.
  6. Twelfth-thirteenth visit (duplicate of Third and fourth visit). These visits are used to evaluate the impact of the training program on the performance of the participants to conduct tasks which are not included in the training procedure. Each participant will conduct the task with both passive and powered prosthetic legs on different days.
  7. Fourteenth-fifteenth visits (duplicate of Third and fourth visit). These visits are used to understand the long term effects of the training program on the participants. These visits will be conducted three months after the 13th visits.

Eligibility criteria: Inclusion Criteria:

* 18 years or older;
* unilateral bower limb amputee
* K-level 2 or higher (who are frequent prosthesis users and may benefit from the proposed prosthesis training and use of dEMG controlled powered prosthesis)
* Amputation occurred over 2 years ago
* At least 1 year of experience using their prosthetic leg
* Has used the current socket for at least 6 months without a significant skin issue or major modification
* Are willing to come to NC State University's Centennial Campus to participate in research and be photographed while doing research activities

Exclusion Criteria:

* Have a very short residual shank (the length of the residual limb is ≤15% of the length of intact limb)
* Cannot perform functional ambulation in the community on a daily basis without assistive devices
* Cognitive or visual impairment that affects the participant's ability to provide informed consent or to follow simple instructions during the experiments
* Congenital amputees
* Amputees who use powered prosthetic ankles
* Weight more than 300lbs
* Pregnant Person
* Allergic to latex, which is often contained in medical tapes.

Primary outcomes:
measure: aCOM, anticipatory Center of Mass Excursion when the expected disturbance is introduced
timeFrame: Pre-training (before the training starts), Post-training (immediately after the training), and follow-up evaluation (one month) with both passive and dEMG devices
Secondary outcomes:
measure: Frequency of stepping responses
timeFrame: Pre-training (before the training starts), Post-training (immediately after the training), and follow-up evaluation (one month) with both passive and dEMG devices
measure: Zero-time-lag cross correlation coefficients for bilateral ankle torque
timeFrame: Pre-training (before the training starts), Post-training (immediately after the training), and follow-up evaluation (one month) with both passive and dEMG devices
measure: Prosthesis Embodiment Scale
timeFrame: Pre-training (before the training starts), Post-training (immediately after the training), and follow-up evaluation (one month) with both passive and dEMG devices
measure: Average muscle modules structure correlation
timeFrame: Pre-training (before the training starts), Post-training (immediately after the training), and follow-up evaluation (one month) with both passive and dEMG devices
measure: Scores from Amputee Mobility Predictor (AMP) Test
timeFrame: Pre-training (before the training starts), Post-training (immediately after the training), and follow-up evaluation (one month) with both passive and dEMG devices
measure: Scores from MiniBES Test (Balance Evaluation Systems Test )
timeFrame: Pre-training (before the training starts), Post-training (immediately after the training), and follow-up evaluation (one month) with both passive and dEMG devices
Other outcomes:
Locations:
city: Raleigh
country: United States
facility: North Carolina State University
state: North Carolina
Study officials:
affiliation: NC State University
name: He Huang, PhD
role: PRINCIPAL_INVESTIGATOR
References: