An Uneven Terrain Surface to Improve Locomotor Robustness in People With Amputation

To attain high levels of mobility, people with lower limb amputation must build both the skill and the confidence to rely on their prosthesis in the environments that they will encounter in daily life. The purpose of this research is to determine whether practicing walking on an uneven terrain surface, specifically designed to present a modest, manageable disturbance to walking, can improve balance, locomotor flexibility (i.e. the ability to adapt walking to different walking contexts) and balance confidence, to a greater extent than walking on level ground alone. This preliminary study aims to determine whether uneven terrain walking is feasible and acceptable in the target population, and also to establish preliminary efficacy.

Study Overview

• Status: Recruiting
• Conditions: Amputation
• Intervention / Treatment: Other: Gait practice on an uneven terrain surface; Other: Gait practice on a flat terrain surface

Detailed Description

The long-term focus of this research is to investigate an uneven terrain training paradigm as an intervention to improve locomotor skill and confidence in lower limb prosthesis users; specifically to determine whether by inducing step-to-step variability in a safe environment, through training on an uneven terrain surface, individuals may develop more adaptable gait, and greater confidence in their mobility. We hypothesize that inducing a manageable level of variability into walking patterns during training will lead to greater balance, locomotor flexibility, and balance confidence. The surface has shallow contours that alter foot-ground interactions at each step, disrupting habitual movement patterns.

The aim of this study is to establish feasibility, acceptability and preliminary efficacy of the uneven surface as a mobility training tool for lower limb prosthesis users. Ambulatory lower limb prosthesis users will attend a biomechanics laboratory on two occasions, during which they will complete walking practice sessions on a flat surface and on an uneven surface. A crossover design will be employed, with walking surface order randomized across participants. Preliminary efficacy will be established based on functional tasks and self-efficacy questions administered before and after the sessions on each day. Feasibility and acceptability will be established based on feasibility study objectives from Orsmond & Cohn's feasibility framework.

• Study Type: Interventional
• Enrollment (Anticipated): 10
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jenny A Kent, PhD; Phone Number: 702-895-5949; Email: jenny.kent@unlv.edu
• Study Contact Backup: Name: Szu-Ping Lee, PT, PhD; Phone Number: 702-895-3086; Email: szu-ping.lee@unlv.edu

Study Locations

• United States
  • Nevada
    • Las Vegas, Nevada, United States, 89154
      • Recruiting
      • University of Nevada Las Vegas
      • Contact: Jenny Kent, PhD; Phone Number: 702-895-5949; Email: jenny.kent@unlv.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• lower limb amputation at ankle level or above
• properly fitted with a walking prosthesis, used regularly for home and/or community ambulation
• good socket fit assessed by a score of 7-10 on the socket fit comfort score (Hanspal et at., 2003).
• able to walk for two minutes at a time with or without an assistive device
• willing to travel to the test site two times for training and testing.

Exclusion Criteria:

• leg/foot ulcer/sore or other conditions that cause pain during weight-bearing
• cardiovascular, respiratory or other critical health conditions that preclude moderate physical activity
• unilateral or bilateral upper limb absence or loss at the wrist and above
• diagnosis of cognitive disturbances
• allergy to medical adhesives
• women who are pregnant or think they may be pregnant
• acute illness
• dizziness on the day of testing

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: SINGLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Uneven terrain walking training; Participants will complete walking practice on an uneven terrain surface.	Other: Gait practice on an uneven terrain surface; Participants will walk back and forth on an uneven terrain surface wearing an overhead harness (with zero bodyweight support), at their self-selected comfortable speed.
ACTIVE_COMPARATOR: Flat terrain walking; Participants will complete walking practice on a level surface.	Other: Gait practice on a flat terrain surface; Participants will walk back and forth on a level surface wearing an overhead harness (with zero bodyweight support), at their self-selected comfortable speed.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in single limb stand time from baseline	The duration the participant is able to stand on one limb without touching the floor with the raised foot, out of a maximum of 30 seconds.	Pre- and immediately post- training session on day 1 and pre- and immediately post- training session on day 2.
Change in balance self-efficacy from baseline	Participants will rate on a scale of 0 (not confident at all) to 10 (extremely confident) their confidence in their ability to walk specified distances on the narrow beam.	Pre- and immediately post- training session on day 1 and pre- and immediately post- training session on day 2.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline in average walking speed	Comfortable walking speed during traverses of 30ft laboratory	Pre- and immediately post- training session on day 1 and pre- and immediately post- training session on day 2.
Change from baseline in narrow beam walking distance	Distance travelled on a low level narrow beam without stepping off	Pre- and immediately post- training session on day 1 and pre- and immediately post- training session on day 2.
Change from baseline in horizontal ladder completion time	Time to traverse a horizontal ladder with randomly separated rungs.	Pre- and immediately post- training session on day 1 and pre- and immediately post- training session on day 2.
Change from baseline in average step width during level walking	Mean width of right and left steps during traverses of 30ft laboratory	Pre- and immediately post- training session on day 1 and pre- and immediately post- training session on day 2.
Change from baseline in average step length during level walking	Mean length of right and left steps during traverses of 30ft laboratory	Pre- and immediately post- training session on day 1 and pre- and immediately post- training session on day 2.
Change from baseline in step width variability during level walking	Standard deviation of right and left step widths during traverses of 30ft laboratory	Pre- and immediately post- training session on day 1 and pre- and immediately post- training session on day 2.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Training protocol feasibility assessed by ability to complete 2-min bouts of walking on flat terrain	Assessment of proposed duration of walking training bouts on flat terrain. For each of six training bouts, successful completion of 2-min of walking without trial termination will be recorded (yes/no).	During training session on days 1 and 2 (each up to 45 minutes)
Training protocol feasibility assessed by ability to complete 2-min bouts of walking on uneven terrain	Assessment of proposed duration of walking training bouts on uneven terrain. For each of six training bouts, successful completion of 2-min of walking without trial termination will be recorded (yes/no).	During training session on days 1 and 2 (each up to 45 minutes)
Assessment protocol feasibility assessed by ability to take two steps or more on narrow beam	Assessment of feasibility of narrow beam-walking task. Ability to take at least two steps on a narrow beam after training session (yes/no).	Immediately post- training sessions on days 1 and 2
Protocol acceptability assessed by session duration	Duration of each session including testing and training in minutes.	During training session on days 1 and 2 (each up to 45 minutes)
Training protocol acceptability assessed by training acceptability questionnaire	Five item self-report Likert-style acceptability questionnaire, assessing the following components for uneven terrain training: 1) enjoyment, 2) challenge, 3) perceived safety, 4) tiredness after training, 5) desire to practice further	Immediately after training on either day 1 or day 2

Collaborators and Investigators

• Sponsor: University of Nevada, Las Vegas
• Investigators: Principal Investigator: Jenny A Kent, PhD, University of Nevada, Las Vegas

Publications and helpful links

General Publications

• Orsmond GI, Cohn ES. The Distinctive Features of a Feasibility Study: Objectives and Guiding Questions. OTJR (Thorofare N J). 2015 Jul;35(3):169-77. doi: 10.1177/1539449215578649.
• Hanspal RS, Fisher K, Nieveen R. Prosthetic socket fit comfort score. Disabil Rehabil. 2003 Nov 18;25(22):1278-80. doi: 10.1080/09638280310001603983.

Study record dates

Study Major Dates

• Study Start (ACTUAL): July 1, 2022
• Primary Completion (ANTICIPATED): August 30, 2023
• Study Completion (ANTICIPATED): December 31, 2023

Study Registration Dates

• First Submitted: September 16, 2022
• First Submitted That Met QC Criteria: September 28, 2022
• First Posted (ACTUAL): September 29, 2022

Study Record Updates

• Last Update Posted (ACTUAL): November 30, 2022
• Last Update Submitted That Met QC Criteria: November 23, 2022
• Last Verified: November 1, 2022

More Information

Terms related to this study

• Keywords: gait; rehabilitation; motor learning; locomotion; lower limb amputation
• Other Study ID Numbers: UNLV-2021-52

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No