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

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

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

Conditions
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Amputation

Intervention / Treatment
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* Other: Gait practice on an uneven terrain surface
* Other: Gait practice on a flat terrain surface


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Participants will be randomized into two groups - 1) uneven - flat; 2) flat - uneven. Uneven and flat sessions will occur on separate days, 12-72 hours apart.
Masking: Single


Arms and Interventions

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

What is the study measuring?
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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. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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locomotion, gait, rehabilitation, motor learning, lower limb amputation