The Ethnocare Underlay is officially back in stock, with all sizes of the Open and Closed versions available for purchase!
After a period of limited availability due to high demand, we're excited to announce that our Underlay inventory has been fully replenished.
Designed specifically for people with below-knee amputations, the Ethnocare Underlay helps address one of the most common challenges associated with wearing a prosthesis: excessive sweating, heat buildup, and moisture trapped inside the prosthetic liner.
Whether you're an active amputee looking for greater everyday comfort or a prosthetist searching for new solutions for your patients, the Underlay offers an innovative approach to prosthetic sweat management.
Shop the Underlay:
Why Are Heat and Sweat Such Common Problems for Prosthetic Users?
For many lower-limb amputees, excessive sweating inside a prosthetic liner is a daily challenge.
Most prosthetic liners are made from materials such as silicone, polyurethane, or thermoplastic. While these materials are essential for cushioning and suspension, they also create a largely enclosed environment around the residual limb.
As body temperature rises during walking, exercise, or everyday activities, perspiration can become trapped between the skin and the liner.
This excess moisture can contribute to:
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Uncomfortable heat and humidity inside the prosthesis.
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Skin irritation and moisture-related discomfort.
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Unpleasant odors.
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Increased friction and potential liner slippage.
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Frequent interruptions to remove the prosthesis and dry the residual limb.
Traditional prosthetic socks primarily help manage socket fit and residual limb volume changes. However, managing moisture directly underneath the prosthetic liner requires a different approach.
That's why we developed the Ethnocare Underlay.
What Is the Ethnocare Underlay?
The Ethnocare Underlay is a specially engineered, moisture-wicking textile sleeve worn directly against the residual limb, underneath the prosthetic liner.
Unlike conventional prosthetic socks worn outside the liner, the Underlay is designed to manage heat, sweat, and humidity at the skin-to-liner interface.
Its innovative textile construction helps transport moisture away from the skin and toward a breathable evaporation zone, reducing the accumulation of perspiration inside the prosthetic liner.
The Underlay combines three key technologies:
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Moisture-wicking knitted fabric that helps transport sweat away from the skin.
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StayCool technology designed to provide a cooling effect.
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StayFresh antimicrobial treatment that helps control odor-causing bacteria on the textile.
Together, these features create a lightweight solution designed to improve comfort without requiring major modifications to an existing prosthetic setup.
How Does the Underlay Work? Understanding Its Moisture-Wicking Design
The secret behind the Underlay lies in its specialized knitted structure.
When perspiration accumulates beneath a conventional prosthetic liner, moisture has limited opportunities to escape because the liner acts as a barrier between the skin and surrounding air.
The Underlay addresses this challenge through capillary action.
Its engineered knit helps transport moisture away from the skin and upward through the textile toward a breathable mesh section.
This breathable section is designed to extend beyond the upper edge of the prosthetic liner, where it can be exposed to air.
Once moisture reaches this evaporation zone, it has an opportunity to evaporate naturally rather than remaining trapped beneath the liner.
The result is a continuous moisture-management pathway designed to help the residual limb feel drier and more comfortable throughout the day.
This mechanism is especially valuable for people who experience excessive perspiration during exercise, physical work, or warmer weather.
Underlay Open: Managing Sweat While Maintaining Prosthetic Suspension
One of the most distinctive features of the Underlay is its Open version, which was specifically engineered to help preserve contact between the skin and the prosthetic liner.
Why Does the Underlay Open Have a Hole at the Bottom?
Prosthetic suspension systems often rely on friction, grip, and direct contact between the residual limb and the liner to maintain stability.
Adding fabric between the skin and the liner can potentially affect this contact.
To address this challenge, the Underlay Open features an intentionally uncovered distal section.
This design allows the bottom portion of the residual limb to remain in direct contact with the prosthetic liner, helping maintain the grip needed for suspension.
When properly positioned, approximately 10 cm (4 inches) of the distal residual limb remains uncovered by the Underlay.
Meanwhile, the textile covers the remaining portion of the residual limb to help manage heat and moisture.
Benefits of the Underlay Open
Preserved distal skin-to-liner contact
The open-bottom design allows the liner to maintain direct contact with the distal residual limb, an important consideration for certain suspension systems.
Effective moisture management
The specialized knitted textile transports perspiration toward the breathable evaporation zone above the liner.
Enhanced airflow and evaporation
The upper breathable section extends beyond the liner, allowing moisture to evaporate more easily.
Compatibility with existing prosthetic systems
The Underlay Open can be especially relevant for users of pin-lock and certain seal-in suspension systems, depending on their individual prosthetic setup.
Underlay Closed: Complete Coverage for Different Prosthetic Needs
Not every prosthetic user requires an open-bottom design.
That's why Ethnocare also developed the Underlay Closed, which offers the same moisture-management technologies with a fully enclosed distal end.
Unlike the Open version, the Underlay Closed covers the entire residual limb underneath the liner.
This configuration can be particularly beneficial for people with more bulbous residual limb shapes or those who prefer complete textile coverage.
It can also be appropriate for certain suspension sleeve and suction configurations, depending on clinical assessment.
Benefits of the Underlay Closed
Complete residual limb coverage
The closed design provides textile coverage across the distal end of the residual limb.
Moisture and heat management
The same moisture-wicking construction helps move perspiration toward the breathable evaporation zone.
Odor-control technology
The StayFresh treatment helps reduce odor-causing bacterial growth on the textile.
An alternative fit configuration
The enclosed design provides another option for users whose limb shape or suspension setup may be better suited to complete distal coverage.
Underlay Open vs. Closed: Which Version Should You Choose?
Both versions are designed to manage sweat, heat, and moisture underneath a prosthetic liner. The key difference is how the textile covers the distal portion of the residual limb.
| Feature | Underlay Open | Underlay Closed |
|---|---|---|
| Distal coverage | Open, allowing direct skin-to-liner contact | Fully enclosed |
| Moisture-wicking technology | Yes | Yes |
| StayCool technology | Yes | Yes |
| StayFresh treatment | Yes | Yes |
| Breathable evaporation zone | Yes | Yes |
| Typical consideration | Preserving distal liner contact | Full coverage and certain limb shapes |
The correct configuration depends on your residual limb shape, prosthetic liner, suspension system, and individual needs.
We recommend consulting your prosthetist when selecting between the Open and Closed versions.
StayCool and StayFresh: Advanced Textile Treatments for Everyday Comfort
Beyond its moisture-wicking construction, the Underlay incorporates specialized textile treatments designed to improve the experience of wearing a prosthetic liner.
StayCool: Cooling Technology for Prosthetic Comfort
Excessive heat is one of the most common complaints among prosthetic users.
Ethnocare's Underlay incorporates StayCool technology, a textile treatment designed to create a cooling sensation and improve thermal comfort.
The technology has demonstrated a 2–3°C (approximately 4–5°F) reduction in fabric temperature under tested conditions.
This cooling effect complements the moisture-wicking knit, helping address both the sensation of heat and the accumulation of perspiration.
Importantly, the reported temperature reduction relates to fabric temperature, not a guaranteed reduction in skin temperature.
StayFresh: Helping Control Unwanted Odors
Heat and trapped moisture can create favorable conditions for odor-causing microorganisms.
The Underlay incorporates Polygiene StayFresh® technology, an antimicrobial textile treatment designed to inhibit the growth of odor-causing bacteria on the fabric.
By controlling bacterial growth on the textile, StayFresh helps the Underlay remain fresher during use.
This treatment complements regular washing and care. It does not replace proper hygiene or prevent skin infections.
Together, StayCool and StayFresh enhance the Underlay's moisture-management construction to provide a more comfortable everyday experience.
What Do the Results Say? Underlay Testing and User Feedback
At Ethnocare, product development is guided by the real-world challenges experienced by amputees.
During product evaluations, the Underlay demonstrated encouraging results related to moisture and thermal comfort.
Users reported:
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51% reduction in perceived humidity.
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38% reduction in perceived heat.
Objective testing also recorded a 17% reduction in relative humidity under the evaluated conditions.
These findings support the potential of the Underlay's moisture-management approach.
However, individual experiences may vary depending on activity level, environmental conditions, liner type, suspension system, and residual limb characteristics.
To explore the evaluation in greater detail, read our Underlay Case Study: Reducing Heat and Humidity Inside a Prosthetic Liner.
How to Find the Correct Underlay Size
Proper sizing is essential for comfort and effective integration with your prosthetic liner.
The Underlay is available in several circumference and length combinations to accommodate different residual limb dimensions.
Because the Open and Closed configurations have different fitting considerations, choosing the correct size requires more than simply selecting a conventional sock size.
To simplify the process, Ethnocare developed an online sizing tool that guides users through the required measurements step by step.
Find Your Underlay Size with the Ethnocare Size Finder
Your prosthetist can also assist you in determining the most appropriate configuration and size for your prosthetic setup.
The Ethnocare Underlay Is Back in Stock: Find Your Size Today!
With all sizes of the Underlay Open and Underlay Closed now restocked, it's the perfect opportunity to discover a new approach to managing prosthetic sweat, heat, and humidity.
Whether you're an amputee looking to improve your everyday comfort or a clinician searching for solutions to help your patients, the Underlay was developed with one objective in mind: making prosthetic use more comfortable and practical.
At Ethnocare, the well-being and mobility of amputees are at the heart of everything we do.
Save 25% When Purchasing Six Underlays
To make daily rotation more convenient and affordable, Ethnocare offers a special multi-unit discount.
A single Underlay is priced at $40 USD, while purchasing six brings the total to $180 USD instead of $240 USD.
That's a 25% discount, bringing the individual price down to $30 USD per Underlay.
Eligible six-unit purchases also qualify for free shipping.
Explore the Underlay and find the version that's right for you:
Have questions about sizing, compatibility, or using the Underlay with your prosthesis? Contact our team or speak with your prosthetist to learn more.
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