INFLUENCE OF A SLOPE ADAPTIVE FOOT ON PARTICIPATION OF VETERANS WITH LOWER-LIMB AMPUTATIONS

Significance to VA: Over 90% of Veterans who use a below-knee prosthesis in the community are prescribed an energy storage and return (ESAR) foot. ESAR feet are designed to assist with forward propulsion during walking, which many users find helpful for certain activities. However, ESAR feet lack ankle articulation, making it difficult to walk on non-level surfaces. To overcome this limitation, typical hydraulic feet incorporate damped ankle motion to accommodate walking on uneven terrain. While potentially improving aspects of participation and fall-related health, typical hydraulic feet have reduced energy storage and return compared to ESAR feet. To combine the benefits of ESAR and typical hydraulic feet, the Minneapolis VA, in collaboration with Fillauer Motion Control, Inc., has developed a novel hydraulic Slope Adaptive Foot (SAF). During pilot testing, most Veterans preferred the SAF over their prescribed ESAR foot and reported improvements in participation. Further research is needed to evaluate the impact of different prosthetic feet on participation and fall-related health in order to identify which patients are best suited for an ESAR foot, a typical hydraulic foot, or the SAF. Innovation and Impact: The long-term goal of this project is to inform prescription of hydraulic feet for Veterans living with lower-limb amputation to optimize their participation in important life roles and activities. Results of this study will help to develop evidence-based provider training and patient education materials to assist with precision rehabilitation and a patient-centered care approach to prescribing hydraulic prosthetic feet. Aim 1 – Evaluate the influence of different prosthetic foot-related factors on participation. PROMIS Ability to Participate in Social Roles and Activities (APSRA) and PROMIS Satisfaction with Social Roles and Activities (SSRA) will be administered during a cross-over randomized control trial (RCT). We hypothesize that using the SAF will be associated with greater APSRA and/or SSRA scores relative to a typical hydraulic foot and that using either hydraulic foot will be associated with greater APSRA and/or SSRA scores compared to the ESAR foot. Aim 2 – Characterize the lived experiences of Veterans using their preferred prosthetic foot to inform clinical decision making. Using mixed-methods, we will explore how participation in social roles and activities is influenced by hydraulic and ESAR feet. Gaining a deeper understanding of Veterans' experiences across a range of situations and environments will inform the development of evidence-based education materials. Exploratory aim – Evaluate the influence of different prosthetic foot-related factors on fall-related health outcomes. The Prosthetic Limb Users Survey of Fall-Related Health (PLUS-FRH), which includes four distinct and important domains, will be administered during a cross-over RCT. We hypothesize that using the SAF will be associated with improved fall-related health outcomes relative to a typical hydraulic foot and that using either hydraulic foot will be associated with improved fall-related health outcomes compared to the ESAR foot. Methodology: To address these aims, we propose to 1) conduct a cross-over RCT of the SAF versus a typical hydraulic foot (Motion Foot SLX, Fillauer) among 30 Veterans with a below-knee amputation who use an ESAR foot and have no prior experience with a hydraulic foot, and 2) conduct a one-year observational study in which Veterans use their preferred prosthetic foot. Participants will complete quantitative (PROMIS-APSRA, PROMIS- SSRA, PLUS-FRH) and qualitative (semi-structured interviews) assessments at baseline and after each period of the cross-over RCT and quarterly during the one-year observational study. A participatory method will be used in which Veterans will be asked to share photos with a short narrative to portray their experiences with their preferred prosthetic foot to prompt discussion during the qua Project Number: 1I01RD000673-01A1 | Fiscal Year: 2026 | NIH Institute/Center: Veterans Affairs (VA) | Principal Investigator: Sara Koehler-McNicholas (+1 co-PI) | Institution: MINNEAPOLIS VA MEDICAL CENTER, MINNEAPOLIS, MN | Activity Code: I01 | Study Section: Behavioral Health & Social Reintegration[RRD4] View on NIH RePORTER: https://reporter.nih.gov/project-details/11246152