# Evolution of an Adaptable Prosthetic Foot Design for Normalization of Biomechanics During Community Participation

> **NIH NIH R42** · OHIO WILLOW WOOD COMPANY · 2020 · $540,223

## Abstract

Evolution of an Adaptable Prosthetic Foot Design for Normalization of
 Biomechanics During Community Participation
Summary/Abstract
 The vision of this project is to improve the functional physical mobility of people with lower extremity
amputations especially on uneven ground, side-slopes or when foot placement varies from side-to-side. People
with amputations will be enabled to confidently participate in a wider range of activities. This will enhance their
personal satisfaction thereby improving their quality of life. People using prostheses currently have significant
mobility disability and a high incidence of falls, partly because commercially available prosthetic feet are unable
to meet their day-to-day needs.
 Current prosthetic feet are designed and optimized for level-ground, forward walking. Consequently,
prosthetists align the prosthetic foot to a single preferred position for this activity. During everyday activities,
including quiet standing, feet are placed in different positions. When the prosthesis user ambulates around
their community, they are faced with many obstacles that do not conform to the level-ground forward walking
paradigm. When people engage in tasks while they walk, or if they have poor limb function, the placement of
the foot becomes less controlled. Thus there is a need to fundamentally rethink prosthetic foot design to
restore adaptability to body-ground position.
 The innovative approach pursued in this project is to develop the Ankentro which restores spontaneous
adaptability, allowing the prosthesis user to ambulate over various terrains. The novel, spontaneously
adaptable foot allows a range of alignments relative to the ground to accommodate a variety of postures and
gait. This is achieved by specific linkages that respond to environmental forces with predictable results,
moving the center of rotation so that it aligns to the resultant forces. Rather than incorporating compliant
surfaces, which can cause postural and gait instability and higher energy cost, the Adaptable Foot restores
adaptability without sacrificing stability.
 During the Phase II effort, the project team will develop a new prosthetic foot called the Ankentro that
includes the linkage system resulting from the Phase I milestone achievements and then use that refined
prototype for extended community use and evaluation. Ankentro development includes optimizing the linkage
mechanism, developing a new toe and heel spring, refining foot covering dimensions, and validating the design
with standardized mechanical tests. The clinical evaluations include controlled laboratory tests that challenge
side-to-side adaptability, in parallel with community trials. Quantitative and qualitative outcomes will be
generated to evaluate the clinical benefit of the Ankentro.

## Key facts

- **NIH application ID:** 9910426
- **Project number:** 5R42HD093476-03
- **Recipient organization:** OHIO WILLOW WOOD COMPANY
- **Principal Investigator:** James Colvin
- **Activity code:** R42 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $540,223
- **Award type:** 5
- **Project period:** 2017-09-05 → 2022-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9910426

## Citation

> US National Institutes of Health, RePORTER application 9910426, Evolution of an Adaptable Prosthetic Foot Design for Normalization of Biomechanics During Community Participation (5R42HD093476-03). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/9910426. Licensed CC0.

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