Enhancing Motor Function in Individuals with Lower Limb Amputation

Enhancing Motor Function in Individuals with Lower Limb Amputation Through Peer-Based Balance and Fall Recovery Skill Training

The overall goal of this research project is to investigate the effectiveness and the science of peer-based prosthetic skill training in individuals with leg amputation. Our belief is that amputee learners will show improved skill learning when observing demonstrations from other amputees, as opposed to observing nonamputee models. The investigators will accomplish the objective by answering the following two questions:

Question 1: Does peer-based observation training works better for learning motor tasks for individuals with lower limb amputation (LLA)?

Question 2: Are there differences in visual focus, behavior, and brain activation patterns when observing motor task demonstrations from amputee peers vs. non-amputees?

Participants of this study will be asked to learn a balance and a fall recovery task by observing video demonstrations by amputee peers vs. non-amputees. The investigators will compare which setting produce better learning.

Study Overview

• Status: Recruiting
• Conditions: Amputation
• Intervention / Treatment: Behavioral: Balance and fall recovery training

Detailed Description

Objective/Hypothesis: The overall objective of this project is to investigate the clinical scientific bases of peer observation sensori-motor skill training in individuals with lower limb amputation. The general hypothesis is that participants observing models who share the same levels of amputation with them (i.e. amputee peers) will exhibit traits of enhanced motor learning when compared to observing non-amputee models. Knowledge gained from this study will directly benefit the development of more effective rehabilitation protocols and has the potential to fundamentally transform the clinical practice of post-amputation rehabilitation.

Aim 1: Determine the effects of peer-based observation training on sensori-motor performance and learning in individuals with LLA. During a 2-week training period, the investigators will assess the differences in task performance and learning outcomes between participants who are instructed to learn to perform the tasks (i.e. balance and reactive fall arrest) by observing video demonstrations from amputee peers vs. non-amputees (n=20).

Aim 2: Examine the differences in visual focus, behavioral psychometrics, and brain activation patterns during and after observing motor task demonstrations from amputee peers vs. non-amputees. The investigators will compare the differences in visual focus time, task-specific self-efficacy, adopted mindset, and event-related brain activation patterns between the two conditions where participants learn to perform the motor tasks demonstrated by amputee peers vs. non-amputees.

Study Design: This research will use a cross-over design with a washout period to expose the participants to the two conditions in random order. In Aim 1, participants with unilateral LLA will be instructed to watch video demonstration of balance and fall recovery tasks performed by either an amputee peer or non-amputee with the intention of learning to perform the task. The subsequent 2-week training will consist of 60 practice trials for each task (over at least 3 sessions).

Participant's task performance (measured by time-in-balance during the balance task, and peak trunk flexion angle and rate of successful fall arrest during the fall recovery task) will be tracked before, throughout, and after (retention) training. To accomplish Aim 2, the investigators will evaluate and quantitatively measure the participant's visual focus (using eye tracking technology), psychometric traits (self-efficacy, motivation, and growth mindset), and brain activation patterns (assessed by electroencephalography, EEG) during the video observation and the corresponding training period.

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Szu-Ping Lee, PhD; Phone Number: 702-895-3086; Email: szu-ping.lee@unlv.edu
• Study Contact Backup: Name: Joel Snyder, PhD; Phone Number: 7028954692; Email: joel.snyder@unlv.edu

Study Locations

• United States
  • Nevada
    • Las Vegas, Nevada, United States, 89154
      • Recruiting
      • University of Nevada, Las Vegas
      • Contact: Szu-Ping Lee, PhD; Phone Number: 7028953086; Email: szu-ping.lee@unlv.edu
      • Contact: Fu-Lien Wu, PhD; Phone Number: 2132758254; Email: fu-lien.wu@unlv.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 1) have unilateral lower limb amputation,
• 2) age >18 years,
• 3) are properly fitted with a walking prosthesis and use it regularly with at least moderate proficiency (K-2 level or above, further defined as scoring greater than 50 percentile on the Prosthetic Limb Users Survey of Mobility),
• 4) able to stand for at least 5 minutes without using an assistive device or experiencing excessive fatigue,
• 5) willing to travel to UNLV 6 times for training and testing.

Exclusion Criteria:

• 1) have other concurrent central nervous system diseases that influence motor function and balance,
• 2) have leg/foot ulcer or other conditions that cause pain during weight-bearing,
• 3) have cardiovascular, respiratory or other critical health conditions that preclude moderate physical activity.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Amputee peers; This research uses a cross-over design to expose the participants with lower limb loss to the two training conditions (observing amputee peers vs. non-amputees) in random order, with a 4-week washout period between conditions. In this arm, participants are instructed to learn from video demonstrations by amputee peers. The videos will show balance and fall recovery movement tasks performed by the models, 15-30 seconds in length. The instruction to the participants is: "Please watch and learn the tasks as performed by the demonstrator. You (the participant) will be asked to perform these tasks later."	Behavioral: Balance and fall recovery training; Following the video observation described in the arms, participants will undergo training to physically practice the motor tasks. The training will take place over a 2-week period encompassing 40 practice trials for each task over the training sessions. During training, the investigators will continuously monitor the changes in balance and fall recovery task performance, and will provide feedback. Participants can request to re-watch the demonstration video that they were assigned to at any time.
Experimental: Non-amputees; In this arm, participants with lower limb loss are instructed to learn from video demonstrations by non-amputees. The videos will show balance and fall recovery movement tasks performed by the models, 15-30 seconds in length. The instruction to the participants is: "Please watch and learn the tasks as performed by the demonstrator. You (the participant) will be asked to perform these tasks later."	Behavioral: Balance and fall recovery training; Following the video observation described in the arms, participants will undergo training to physically practice the motor tasks. The training will take place over a 2-week period encompassing 40 practice trials for each task over the training sessions. During training, the investigators will continuously monitor the changes in balance and fall recovery task performance, and will provide feedback. Participants can request to re-watch the demonstration video that they were assigned to at any time.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Balance performance	During balance training, a potentiometer and a timer integrated to the balance platform will monitor the sway angle of the platform and time-in-balance, which is defined as when the platform angle is within ± 5° of horizontal. The primary outcome measure is time in balance (seconds) during each 30-second balance trial.	During the 6-visit training (3 months from the first to last visit)
Fall recovery performance (frequency)	During fall recovery training, the incidence of falls during the trials will be recorded	During the 6-visit training (3 months from the first to last visit)
Fall recovery performance (movement quality)	During fall recovery training, the trunk and lower extremity stepping kinematics during the trials will be recorded	During the 6-visit training (3 months from the first to last visit)
Patient's self-reported psychometric outcomes	Surveys will be used to assess the participant's perceptions about the training, task-specific self-efficacy, and learning mindset. Task-specific self-efficacy questions will be answered on an analog scale of 0-100 and included: "How difficult do you think the task is?", "How confident are you that you will be able to perform the task after practice?", and "How useful do you think this training is when applied to real life situations?". Growth mindset survey will ask the participants to rate a series of statements including: "I can always improve how well I conduct a physical task (such as maintaining balance or walking).", "I only have a certain amount of physical capacity, and I can't really do much to change it.", "Hard work is needed to master skills needed for different tasks.", and "Other people's successes are inspiring. I can learn by their example."	During the 6-visit training (3 months from the first to last visit)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual focus assessment using eye tracking	During demonstration video-watching, monocular recordings of the participant's eye movements will be recorded simultaneously by a desktop mounted eye-tracker. The coded data will be used to compare the visual attentional focus between the amputee-peers vs. non-amputee videos.	During video observations at the beginning of the 6-visit training (1st and 4th visits). The training is 3-months long.
Brain activation pattern assessment using electroencephalography (EEG)	During demonstration video-watching, participants' brain activity will be assessed using a non-invasive, battery-powered EEG recording system with 64 electrodes on their head.	During video observations at the beginning of the 6-visit training (1st and 4th visits). The training is 3-months long.

Collaborators and Investigators

• Sponsor: University of Nevada, Las Vegas
• Collaborators: United States Department of Defense
• Investigators: Principal Investigator: Szu-Ping Lee, PhD, University of Nevada, Las Vegas

Publications and helpful links

General Publications

• Ziegler-Graham K, MacKenzie EJ, Ephraim PL, Travison TG, Brookmeyer R. Estimating the prevalence of limb loss in the United States: 2005 to 2050. Arch Phys Med Rehabil. 2008 Mar;89(3):422-9. doi: 10.1016/j.apmr.2007.11.005.
• Wulf G, Chiviacowsky S, Lewthwaite R. Altering mindset can enhance motor learning in older adults. Psychol Aging. 2012 Mar;27(1):14-21. doi: 10.1037/a0025718. Epub 2011 Oct 10.
• Cusack WF, Thach S, Patterson R, Acker D, Kistenberg RS, Wheaton LA. Enhanced Neurobehavioral Outcomes of Action Observation Prosthesis Training. Neurorehabil Neural Repair. 2016 Jul;30(6):573-82. doi: 10.1177/1545968315606992. Epub 2015 Oct 5.

Study record dates

Study Major Dates

• Study Start (Actual): June 30, 2023
• Primary Completion (Estimated): December 31, 2024
• Study Completion (Estimated): December 31, 2025

Study Registration Dates

• First Submitted: November 27, 2023
• First Submitted That Met QC Criteria: October 10, 2024
• First Posted (Actual): October 15, 2024

Study Record Updates

• Last Update Posted (Actual): October 15, 2024
• Last Update Submitted That Met QC Criteria: October 10, 2024
• Last Verified: October 1, 2024

More Information

Terms related to this study

• Keywords: falls; prosthetics; EEG; motor learning; balance; peer support; limb loss
• Other Study ID Numbers: UNLV-2022-99; W81XWH-22-1-0216 (Other Grant/Funding Number: Department of Defense (CDMRP))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: There is currently not a plan to share participant data with other researchers.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No