Investigating Auto Adjusting Dynamic AFO

October 30, 2026 updated by: Joan E Sanders, University of Washington

Offloading Ankle Foot Orthoses (AFOs) are devices designed for people following lower-limb reconstruction to restore mobility by reducing mechanical loading through the injury site and redistributing it proximally. While they perform well for some users, their current form limits full functional potential and may put joints proximal to the injury at risk of long-term damage. This study is directed toward designing and testing a lightweight, variable stiffness, dynamic brace that can adjust in response to user activity.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

22

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

  • Name: Katheryn Allyn, CPO, LPO
  • Phone Number: 206-390-0228

Study Contact Backup

  • Name: Joan Sanders, PhD
  • Phone Number: 206-221-5872
  • Email: jsanders@uw.edu

Study Locations

    • Washington
      • Seattle, Washington, United States, 98105
        • Recruiting
        • University of Washington, Dept. of Bioengineering
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria (Healthy Volunteers):

-able to run continuously for 1 minute

Inclusion Criteria (All Other Volunteers)

  • prescribed an offloading Ankle-Foot Orthosis (AFO) for walking/running
  • Use prescribed offloading AFO at least 20 hours per week
  • Prescribed AFO strut length of at least 200 mm
  • Able to run continuously for 1 minute

Exclusion Criteria (Healthy Volunteers):

  • limited sensation in the lower limbs
  • use an assistive device

Exclusion Criteria (All Other Volunteers):

  • Unable to ambulate (walk/run) continuously with AFO for at least 1 minute
  • Unable to sit, stand, or negotiate a step onto lab treadmill

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Supportive Care
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Aim 2

Participants will carry out a protocol comprised of treadmill walking in a laboratory setting while wearing the Dynamic AFO device.

The Dynamic AFO is able to adjust in stiffness depending on activity.

Experimental: Aim 3

Participants will be asked to take the Dynamic AFO home and wear the device for up to 4 weeks. The device will be set in either an adjustment-capable mode, or a "locked" mode that functions similar to their own orthotic--the order in which they are tested will be randomized.

The Dynamic AFO is able to adjust in stiffness depending on activity.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Time Running Per Day
Time Frame: Calculated across all days of data collection (up to 4 weeks).

Collected while participant uses device in free-living environment.

Calculated across all days of data collection (up to 4 weeks).
Longest Running Bout Duration
Time Frame: Across all days of data collection (up to 4 weeks), the longest bout of continuous activity will be identified (minutes).

Collected while participant uses device in free-living environment.

Across all days of data collection (up to 4 weeks), the longest bout of continuous activity will be identified (minutes).
PROMIS-Fatigue
Time Frame: Following their time out in their free-living environment (up to 4 weeks at a time), participants will be asked to complete a questionnaire related to fatigue.

Participants will be asked to fill out a questionnaire related to their experience using the variable stiffness AFO out of lab in various test configurations. Each PROMIS-Fatigue question asks participants to rank on a scale from 1 to 5 (categorical options), with higher scores indicating a greater level of fatigue.

Following their time out in their free-living environment (up to 4 weeks at a time), participants will be asked to complete a questionnaire related to fatigue.
Pain Score
Time Frame: Following their time out in their free-living environment (up to 4 weeks at a time), participants will be asked to complete a questionnaire related to pain.

Participants will be asked to fill out a questionnaire related to their experience using the variable stiffness AFO out of lab in various test configurations. Each Pain-Score question asks participants to rank on a scale from 1 to 10 (categorical options), with higher scores indicating a greater level of pain.

Following their time out in their free-living environment (up to 4 weeks at a time), participants will be asked to complete a questionnaire related to pain.
Orthotic Evaluation Questionnaire (OEQ)
Time Frame: Following their time out in their free-living environment (up to 4 weeks at a time), participants will be asked to complete an OEQ.

Similar to the Prosthesis Evaluation Questionnaire (PEQ), the OEQ will ask various questions concerning their experience wearing the variable stiffness AFO. Participants will rate their overall satisfaction, ability to ambulate, the health of their limb, the utility of the device, and their overall well-being after wearing the device.

Following their time out in their free-living environment (up to 4 weeks at a time), participants will be asked to complete an OEQ.
Running Speed on Treadmill
Time Frame: In-lab testing will occur over the course of up to 2 hours at a time.

Participants carrying out the in-lab protocol will be asked to run using the variable stiffness AFO and running speed will be documented at various time points.

In-lab testing will occur over the course of up to 2 hours at a time.
Extended Figure-of-8 Test
Time Frame: In-lab testing wil occur over the course of up to 2 hours at a time.

Participants carrying out the in-lab protocol will be asked to do a Figure-of-8 test.

In-lab testing wil occur over the course of up to 2 hours at a time.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Collaborators

Investigators

  • Principal Investigator: Joan E Sanders, PhD, University of Washington

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

November 30, 2020

Primary Completion (Estimated)

November 30, 2027

Study Completion (Estimated)

December 1, 2027

Study Registration Dates

First Submitted

November 2, 2020

First Submitted That Met QC Criteria

November 9, 2020

First Posted (Actual)

November 10, 2020

Study Record Updates

Last Update Posted (Actual)

November 4, 2026

Last Update Submitted That Met QC Criteria

October 30, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • STUDY00009120

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.