An Automatically Adjusting Prosthetic Socket for People With Transtibial Amputation

NCT05124652 | Recruiting FDA Device

• 2 other identifiers: STUDY000094181R01HD103815-01A1
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

People with leg amputations often experience daily changes in the size (volume) of their residual limb. These daily changes can cause a prosthesis to fit poorly. They can also cause limb problems like pain or skin breakdown. Prosthetic socket systems that accommodate limb volume changes can help address these issues, but they require users to make adjustments throughout the day. The aim of this research is to create a system that will automatically adjust the fit of the socket and create a well-fitting prosthesis for people with leg amputations who experience volume fluctuations when using their prosthesis.

Conditions

Lower Limb Amputation Below Knee (Injury); Diurnal Residual Limb Fluid Volume Fluctuation

Keywords

amputee; prosthetic

Outcome Measures

Primary Outcomes (2)

• Socket Comfort Score

  Participants in Aim 2 and Aim 3 will test various configurations of the auto adjustment algorithm. Socket comfort score will be asked at various time points during testing, and overall changes in this metric will be calculated from the start and end of session.

  through study completion, an average of 1 year

• Integral Absolute Error of Control System

  Calculated error will be measured through each test session, both in and out of lab.

  through study completion, an average of 1 year

Secondary Outcomes (5)

• Percent change in Limb Fluid Volume

  through study completion, an average of 1 year

• Residual limb health

  Baseline and through study completion, an average of 1 year

• Prosthesis wear time

  Up to 12 weeks

• Time of activities

  Up to 12 weeks

• Variability in socket fit

  Up to 12 weeks

Other Outcomes (2)

• Number of manual socket size adjustments

  Up to 12 weeks

• Participant socket preference and qualitative interview responses

  Through study completion, an average of 1 year

Study Arms (3)

Focus Group Testing

NO INTERVENTION

Focus group testing of key-fob device to control adjusting socket system

In-Lab, Crossover Study

EXPERIMENTAL

Testing of auto-adjusting algorithm in-lab. Participants will carry out a structured protocol wearing the socket in all modes. Order will be randomly assigned.

Device: Auto Adjusting Prosthesis

Out-of-Lab Crossover Study

EXPERIMENTAL

Evaluate socket performance in user free-living environments. Participants will use the prosthesis in all modes by end of study, order will be randomly assigned.

Device: Auto Adjusting Prosthesis

Interventions

Auto Adjusting Prosthesis DEVICE

Participants will test the auto adjusting prosthesis. The prosthesis will be able to move up to 3 panels built into the socket walls to expand or tighten the socket's fit. The auto adjustments will take place during periods of sitting, standing, or walking. Manual adjustments will also be possible either via the researcher controlling the prosthesis or via the key fob developed in the first aim.

In-Lab, Crossover Study; Out-of-Lab Crossover Study

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

* 18 years or older * Unilateral or bilateral trans-tibial amputation at least 12 months prior * Have a limb of length 9 cm or greater * Are capable of at least 5 minutes of continuous walking * Are capable of at least 1 hour of intermittent walking * Regularly use a definitive prosthesis with a pin-lock suspension system and no or few pads * Have adequate sensation to verbalize a socket that is too large or too small to be tolerated * Do not regularly use assistive devices (e.g., cane, walker) for ambulation * Do not have open wounds on their residual limb at the time of enrollment

Contact the study team to discuss eligibility requirements. They can help determine if this study is right for you.

Sponsors & Collaborators

• University of Washington: lead
• Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD): collaborator

Study Sites (1)

William H. Foege Hall

Seattle, Washington, 98105, United States

RECRUITING

MeSH Terms

Conditions

Wounds and Injuries

Study Officials

• Joan E Sanders, PhD

  University of Washington

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Katheryn Allen, CPO

CONTACT

206-390-0228; kate@allyn.org

Tessa S Viljamaa

CONTACT

tessasv@uw.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor: Engineering

Model Details: All aims will be conducted as randomized control trials and test various developments to the auto adjusting system, with each previous aim informing the next.

Study Record Dates

• First Submitted: October 20, 2021
• First Posted: November 18, 2021
• Study Start: October 18, 2021
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): June 1, 2027
• Last Updated: May 7, 2026

Record last verified: 2026-03

Locations

US (1)