Adherence and Perspiration While Wearing Lower Limb Prostheses

Summary

Individuals with lower limb amputation often complain about uncomfortable residual limb skin temperatures and the accumulation of sweat inside their prostheses. It doesn't take long before the presence of sweat on the residual limb leads to a lack of confidence in the security of their prosthetic suspension. Some circumstances allow the wearer to doff the prosthesis before it falls off, wipe it and the residual limb dry, and then don it again. Another option is to simply reduce the intensity of activities before sweat becomes a problem. However, the Warfighter amputee may not be afforded such accommodations. For these service personnel, inadequate moisture management can significantly limit or inhibit their mobility. The objective of the proposed research is to provide lower limb amputees who work in demanding environments with a prosthesis that remains secure despite profuse residual limb sweating without compromising residual limb health and comfort.

The aim of this research is to compare three different, lower limb prosthetic suspension systems and identify which is most effective at maintaining a secure adherence when worn in conditions that result in profuse sweating. The investigators also aim to compare how the three study prostheses effect residual limb skin health and comfort when participants pursue their usual activities in the home, work, and community environments.

To achieve these aims, the investigators will to recruit 25 below-knee amputees. Each subject will be asked to be asked to wear: (1) their as-prescribed prosthesis, (2) a prosthesis with a perforated elastomeric liner that allows sweat to flow away from the skin, and (3) a prosthesis that has a battery and body-weight activated pump to flow air between the prosthesis and the residual limb skin, allowing expulsion of any accumulated sweat. Subjects will wear each of these prostheses in the home, work, and community environments for two weeks, after which the investigators will measure their residual limb health and comfort. Subjects will then walk on a treadmill in a room whose climate will be set to Middle East-like conditions: 35 °C (95 °F) and 50% relative humidity. After 30 minutes, the investigators will measure any slippage of their prosthesis relative to their limb and how much sweat is expelled. The investigators hypothesize there will be differences in the amount of slippage, residual limb health, and comfort between the three prostheses.

Conditions

• Lower Extremity Amputation

Interventions

DEVICE

Dynamic Air Exchange - Rising Edge Design (DAE-RED)

The DAE-RED suspension system expels perspiration to the prosthesis exterior using a hybrid battery-powered pump and a body-weight activated pump. To use the DAE-RED, subjects will be fit with a modified patellar tendon-bearing socket that fits over a custom liner and sock. Up to four air intake ports are located proximally on the liner, approximately 25 mm superior to the socket brim. These ports incorporate a microvalve that allows air to flow into the liner-skin interstitial space while still maintaining a vacuum suspension. Distally, the pin lock has a 3-mm hole along its longitudinal axis that allows perspiration to be expelled into a distal reservoir. The prosthesis will also include: a standard aluminum pylon, pyramid adapters, and an Ossur Proflex XC prosthetic foot with Unity pump and foot cover.

DEVICE

Perforated elastomeric liner

The unique element of this perforated elastomeric liner are small perforations (\~0.3 mm diameter), uniformly distributed on a 4 x 5 mm grid, but with no perforations on the distal umbrella, that allow perspiration to be exuded into the liner-socket interstitial space. To use the perforated elastomeric liner, subjects will be fit with a modified patellar tendon-bearing socket that fits over a sock and the perforated elastomeric liner with a pin lock. The sock, worn between the socket and the liner, is used to absorb perspiration that is transported through the perforations in the liner. When needed for residual limb volume control, additional socks will be donned and included in tare weighing. The prosthesis will also include: a standard aluminum pylon, pyramid adapters, and an Ossur Proflex XC prosthetic foot and cosmesis.

DEVICE

As-prescribed prosthesis

The individual's as-prescribed suspension system is the prosthesis prescription that the patient and their clinical care team believes is the best prosthesis for their needs.

Sponsors & Collaborators

• United States Department of Defense

  collaborator FED

• Seattle Institute for Biomedical and Clinical Research

  lead OTHER

Principal Investigators

• Glenn K Klute, PhD · Dept. of Veterans Affairs

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

70 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2019-02-17

Primary Completion

2022-06-28

Completion

2022-06-28

FDA Device

Yes

Countries

• United States

Study Locations