Adjustable Prosthetic Sockets

NCT07397169 | Not Yet Recruiting FDA Device

• 3 other identifiers: RRD2-010-25M1I01RD002103-011924445
• Study Type: interventional
• Target: 25
• Locations: 1 country
• Sites: 1

Brief Summary

Each year, around 1500 Veterans join the 623,000 Americans who live with a lower limb amputation. Many of these Veterans choose the arduous path of rehabilitation to remain ambulatory, a process that includes the prescription of a lower limb prosthesis. Much relies on the goodness of fit of their prosthesis. A good fit feels comfortable and enables a variety of ambulatory activities. A poor fit results in discomfort, often accompanied by chronic skin issues, and activities of daily living are curtailed. Conventional prosthetic sockets are custom-built by a skilled prosthetist, carefully formed to fit the Veteran's residual limb, and good fits can usually be obtained. These sockets are rigid, fixed shape structures with the robustness of a bulldozer, built for sustained, heavy-duty action. Unfortunately, the shape of an individual's residual limb can change over time, such that a good fit eventually becomes poor. One estimate suggests a new below-knee socket is needed every three and a half years. The expense of replacing sockets that no longer fit is not insignificant. Medicare expenditures for replacement of existing below-knee sockets and associated components were estimated at $50M in 2017. Importantly, Medicare is estimated to be only 20% of the market, suggesting the estimated expenditure for the entire population with lower limb amputations is likely to be meaningfully larger. A good fitting prosthesis that maintains its fit over time would serve Veterans well. A potential solution that could make a good fit last longer is an adjustable prosthetic socket. While little evidence is available to support prescription practice, the Centers for Medicare and Medicaid Services (CMS) recently authorized reimbursement for adjustable prosthetic sockets, suggesting a compelling need for such a product. To investigate the potential for deleterious effects and how Veterans might use adjustable prosthetic sockets, the aim of this research is to determine the pressure applied to the residual limb by an adjustable prosthetic socket during activities of varying intensity and the activities that induce adjustments. A laboratory-based human subject experiment will be conducted using a custom sensor placed inside the adjustable panel of a study-provided adjustable prosthetic socket. Participants will acclimate to the adjustable prosthetic socket for two weeks in the field, then return to the laboratory to perform seven activities. The pressure inside the prosthesis will be measured during these activities. Participants will also report how tight their socket feels after each activity.

Conditions

Lower Extremity Amputation

Keywords

lower limb amputation; transtibial amputation; below knee amputation; prosthetic socket; prosthesis

Outcome Measures

Primary Outcomes (14)

• Distal end pressure while seated (5 min bout)

  A pressure transducer will record the distal end residual limb pressure while the participant is seated for 5 minutes. The first four minutes of data will be truncated. The remaining first and last fifteen seconds of the fifth minute will also be truncated. The mean pressure will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments

• Distal end pressure while standing (1 min bout)

  A pressure transducer will record the distal end residual limb pressure while the participant stands for 1 minute. The first and last fifteen seconds will be truncated. The mean pressure will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments

• Distal end pressure while walking at self-selected speed (1 min bout)

  A pressure transducer will record the distal end residual limb pressure while the participant walks at self-selected speed for 1 minute. The first and last fifteen seconds will be truncated. The mean peak pressure from each step with the prosthesis will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Distal end pressure while walking up 10% slope at self-selected speed (1 min bout)

  A pressure transducer will record the distal end residual limb pressure while the participant walks up 10% slope at self-selected speed for 1 minute. The first and last fifteen seconds will be truncated. The mean peak pressure from each step with the prosthesis will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Distal end pressure while walking down 10% slope at self-selected speed (1 min bout)

  A pressure transducer will record the distal end residual limb pressure while the participant walks down 10% slope at self-selected speed for 1 minute. The first and last fifteen seconds will be truncated. The mean peak pressure from each step with the prosthesis will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Distal end pressure while walking 15% faster than self-selected speed (1 min bout)

  A pressure transducer will record the distal end residual limb pressure while the participant walks 15% faster than self-selected speed for 1 minute. The first and last fifteen seconds will be truncated. The mean peak pressure from each step with the prosthesis will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Distal end pressure while walking at self-selected speed (10 min bout)

  A pressure transducer will record the distal end residual limb pressure while the participant walks at self-selected speed for 10 minutes. The first nine minutes of data will be truncated. The remaining first and last fifteen seconds of the tenth minute will also be truncated. The mean peak pressure from each step with the prosthesis will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Adjustable posterior panel pressure while seated (5 min bout)

  A pressure transducer will record the adjustable posterior panel pressure while the participant is seated for 5 minutes. The first four minutes of data will be truncated. The remaining first and last fifteen seconds of the fifth minute will also be truncated. The mean pressure will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Adjustable posterior panel pressure while standing (1 min bout)

  A pressure transducer will record the adjustable posterior panel pressure while the participant stands for 1 minute. The first and last fifteen seconds will be truncated. The mean pressure will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Adjustable posterior panel pressure while walking at self-selected speed (1 min bout)

  A pressure transducer will record the adjustable posterior panel pressure while the participant walks at self-selected speed for 1 minute. The first and last fifteen seconds will be truncated. The mean peak pressure from each step with the prosthesis will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Adjustable posterior panel pressure while walking up 10% slope at self-selected speed (1 min bout)

  A pressure transducer will record the adjustable posterior panel pressure while the participant walks up 10% slope at self-selected speed for 1 minute. The first and last fifteen seconds will be truncated. The mean peak pressure from each step with the prosthesis will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Adjustable posterior panel pressure while walking down 10% slope at self-selected speed (1 min bout)

  A pressure transducer will record the adjustable posterior panel pressure while the participant walks down 10% slope at self-selected speed for 1 minute. The first and last fifteen seconds will be truncated. The mean peak pressure from each step with the prosthesis will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Adjustable posterior panel pressure while walking 15% faster than self-selected speed (1 min bout)

  A pressure transducer will record the adjustable posterior panel pressure while the participant walks 15% faster than self-selected speed for 1 minute. The first and last fifteen seconds will be truncated. The mean peak pressure from each step with the prosthesis will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Adjustable posterior panel pressure while walking at self-selected speed (10 min bout)

  A pressure transducer will record the adjustable posterior panel pressure while the participant walks at self-selected speed for 10 minutes. The first nine minutes of data will be truncated. The remaining first and last fifteen seconds of the tenth minute will also be truncated. The mean peak pressure from each step with the prosthesis will be calculated from the remaining 30 seconds of each trial.

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

Secondary Outcomes (7)

• Tightness while seated (5 min bout)

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Tightness while standing (1 min bout)

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Tightness while walking at self-selected speed (1 min bout)

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Tightness while walking up 10% slope at self-selected speed (1 min bout)

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

• Tightness while walking down 10% slope at self-selected speed (1 min bout)

  After a two-week acclimation period where the participant wears an adjustable prosthetic socket in the home, community, and work environments.

Study Arms (1)

Adjustable prosthetic socket

EXPERIMENTAL

Participants will wear an adjustable prosthetic socket.

Device: Adjustable prosthetic socket

Interventions

Adjustable prosthetic socket DEVICE

The investigators will fabricate and assemble an adjustable prosthetic socket for each participant whose shape is a duplicate of their existing, as-prescribed prosthetic socket. We will add three adjustable panels to the prosthetic socket which will be located over the medial and lateral proximal tibia region and the posterior gastrocnemius region. The position of the panels will be adjustable in and out using a cable mechanism.

Adjustable prosthetic socket

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Veterans with lower limb amputation
• have a unilateral transtibial amputation
• wear a prosthesis for at least 4 hours a day by self-report
• at least one-year post-amputation
• have a modular prosthesis that includes a four-bolt socket attachment
• can walk on a treadmill

You may not qualify if:

• have an improper fit and suspension with their current prosthesis, and a good fit cannot be achieved with clinical resources
• have current skin irritation or injury to the residual limb, osteoarthritis, injury, or pain that interferes with walking ability

Sponsors & Collaborators

• VA Office of Research and Development: lead

Study Sites (1)

VA Puget Sound Health Care System Seattle Division, Seattle, WA

Seattle, Washington, 98108-1532, United States

Location

Study Officials

• Glenn K Klute, PhD

  VA Puget Sound Health Care System Seattle Division, Seattle, WA

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Elise B Campbell, MS BFA BA

CONTACT

(206) 277-6792; elise.campbell@va.gov

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: FED
• Responsible Party: SPONSOR

Model Details: Each participant will wear an instrumented adjustable prosthetic socket.

Study Record Dates

• First Submitted: February 2, 2026
• First Posted: February 9, 2026
• Study Start (Estimated): June 15, 2026
• Primary Completion (Estimated): January 15, 2029
• Study Completion (Estimated): August 1, 2029
• Last Updated: February 9, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF
• Time Frame: Within six months of publication of final study findings.
• Access Criteria: Open access through PubMed Central, SimTK, PhysioNet, or other similar open-source data repository websites. The study protocol, statistical analysis plan, and the informed consent form will be shared on clinicaltrials.gov.

Locations

US (1)