Restoration of Normative Postural Control

Lower Limb Amputation Below Knee (Injury) Clinical Trial

Official title:

Toward Restoration of Normative Postural Control and Stability Using Neural Control of Powered Prosthetic Ankles

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT06452186
• Other study ID #: 26076
• Status: Recruiting
• Phase: N/A
• Start date: October 1, 2023
• Est. completion date: July 30, 2028

Study information

• Verified date: June 2024
• Source: North Carolina State University
• Contact: Neuromuscular Rehabilitation Engineering Laboratory
• Phone: 919-513-3840
• Email: nrel.ncsu.contact[@]gmail.com
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 50
• Est. completion date: July 30, 2028
• Est. primary completion date: July 1, 2027
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 99 Years

Eligibility

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.

Related Conditions & MeSH terms

• Lower Limb Amputation Below Knee (Injury)

Intervention

Device:
• direct EMG controlled prosthetic ankle
Patients are trained to use the powered prosthetic ankles

Behavioral:
• PT guided prosthetic training
Amputees are trained to use prosthetic ankles

Locations

Country	Name	City	State
United States	North Carolina State University	Raleigh	North Carolina

Sponsors (2)

Lead Sponsor	Collaborator
North Carolina State University	University of North Carolina, Chapel Hill

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	aCOM, anticipatory Center of Mass Excursion when the expected disturbance is introduced	This measurement is to quantify the movement of the COM at the time when the disturbance is introduced and represents an important element of the capability of the participants to conduct anticipatory. Higher value indicates better capacity to conduct anticipatory postural control.	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	Frequency of stepping responses	Number of amputees to conduct steps to recover from disturbance divided by total number of disturbance, which they experienced.	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	Zero-time-lag cross correlation coefficients for bilateral ankle torque	Torque in the anterior-posterior direction. This outcome quantify the symmetry between the prosthetic ankle and the unaffected ankle when the participants try to maintain balance under expected disturbance	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	Prosthesis Embodiment Scale	The Prosthesis Embodiment Scale for Lower Limb Amputees (PEmbS-LLA) measures amputees' feeling of ownership, sense of agency, and anatomical plausibility of a lower limb prosthetic device. This scale has been tested on lower limb amputees using daily prescribed prosthesis (not neurally controlled) with established validity and reliability. The score range is -3~3 and high value indicates better embodiment.	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	Average muscle modules structure correlation	Correlation coefficient of muscle modules structures identified using nonnegative matrix factorization (NNMF) during a voluntary postural sway task. This measure is used to determine whether muscle modules employed between populations are meaningfully similar.	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	Scores from Amputee Mobility Predictor (AMP) Test	Clinical balance outcomes used to measure the capacity of participants to conduct functional tasks, which are related to balance. The score ranges from 0-47. Higher values indicate better performance.	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	Scores from MiniBES Test (Balance Evaluation Systems Test )	Clinical balance outcomes used to measure the capacity of participants to conduct functional tasks, which are related to balance. The score ranges from 0 to 28. The higher value indicates better balance capability	Pre-training (before the training starts), Post-training (immediately after the training), and follow-up evaluation (one month) with both passive and dEMG devices