Long Term Clinical Evaluation of SLS Transtibial Sockets

April 24, 2017 updated by: The University of Texas Health Science Center at San Antonio

The overall long-term goal of this project is the development of a clinically practical system for rapid prosthetic limb provision that integrates computer-aided design with solid freeform fabrication techniques. This proposal builds on our previous successful demonstration of the feasibility of SFF socket fabrication and will address several key issues that underlie its clinical viability. The specific objectives of the proposed work are:

To develop improved designs for SFF transtibial prosthetic sockets that allow the use of industry standard pylon mounts and incorporate variable compliance elements.
Determine the clinical effectiveness of variable wall compliance elements in enhancing the comfort and fit of transtibial prosthetic sockets.
Determine the durability and functionality of SFF sockets during extended clinical use.

These objectives will be met over a three-year period. The initial phase of the proposed work will use an iterative engineering design - modeling - evaluation process to develop variable compliance elements and an industry standard pylon mount adapter. During the second phase of the proposed work, clinical evaluations of SFF prosthetic sockets will be studied. The effectiveness of variable compliant elements in enhancing comfort and fit will be determined using a within subject case comparison study of SFF sockets with conventional laminated sockets. Durability of SFF sockets that incorporate an industry standard pylon mounting system will be determined during a 12-month clinical field trial.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Device: Prosthetic socket fabricated using selective laser sintering

Detailed Description

Successful rehabilitation for the majority of lower extremity amputees includes prosthetic limb fitting and training. Critical to the success of prosthetic fitting is a comfortable, well fitting socket. Accomplishing this remains a clinical challenge with residual limb pain and socket discomfort affecting 20-55% of lower limb amputees. Achieving an acceptable socket fit using conventional prosthetic techniques requires individual custom molding and fabrication in a labor intensive, costly process. Alternative methods of fabricating prosthetic sockets that can improve efficiency in prosthetic provision, enhance comfort and fit, or reduce cost are needed to ensure the continued optimal rehabilitation of the amputee. This project will continue the development of a new promising method of socket fabrication using solid freeform fabrication (SFF) based on selective laser sintering (SLS) technology. SFF allows the direct manufacture of a prosthetic socket without the intermediate molds and laminating process required with conventional techniques.

To develop improved designs for SFF transtibial prosthetic sockets that allow the use of industry standard pylon mounts and incorporate variable compliance elements.
Determine the clinical effectiveness of variable wall compliance elements in enhancing the comfort and fit of transtibial prosthetic sockets.
Determine the durability and functionality of SFF sockets during extended clinical use.

Study Type

Observational

Enrollment (Actual)

Contacts and Locations

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

Study Locations

United States
- Texas
  - San Antonio, Texas, United States, 78229
    - South Texas Veterans Healthcare System

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:

All subjects will be lower extremity amputees of at least one year duration and are 18 years of age or older.

They must meet the Medicare Functional Classification Level K2 or K3 class for prosthetic use (unlimited household or limited community level ambulator).

Exclusion Criteria:

There must be no current stump wounds or breakdown or a history of repeated skin breakdown with adequately fitting prostheses.

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?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Durability during household and community mobility. Time Frame: Up to 12 months	Subjects were followed for up to 12 months in 3 months intervals for examination of the physical condition of socket and for subject gait assessment with socket	Up to 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
User perceptions of comfort, fit, and function. Time Frame: Up to 12 months	Subjects were followed up at 3 month intervals and assessed for comfort fit and function	Up to 12 months

Collaborators and Investigators

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

Sponsor

The University of Texas Health Science Center at San Antonio

Investigators

Principal Investigator: Nicolas Walsh, MD, The University of Texas Health Science Center at San Antonio

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

April 1, 2003

Primary Completion (Actual)

July 1, 2011

Study Completion (Actual)

July 1, 2011

Study Registration Dates

First Submitted

September 9, 2005

First Submitted That Met QC Criteria