Substantial redesign of protocol and training warranted new study.

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.

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.

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

Outcomes assessor will be blinded to arm.