Residual limb volume variation is one of the most common daily challenges in lower limb prosthetics. For many prosthetic users, small changes in limb size throughout the day can affect socket fit, comfort, stability, and confidence during movement.
At Ethnocare, this challenge is central to our mission. Our work focuses on helping lower limb amputees manage socket fit more easily, without constantly adding or removing prosthetic socks or stopping their day to make adjustments.
This month, we are excited to share a few important updates, including Alex Dahinten’s recent feature on The Prosthetics and Orthotics Podcast, our upcoming OTWorld 2026 workshop, and a closer look at the clinical potential of the Overlay TF for transfemoral users.
Alex Dahinten Featured on The Prosthetics and Orthotics Podcast
Alex Dahinten, CPO and member of the Ethnocare team, was recently featured on The Prosthetics and Orthotics Podcast in an episode titled:
Design, Engineering, Clinical Passion, and the Future of Patient Managed Comfort
In the episode, Alex shares his journey from biomedical engineering into prosthetics and orthotics, along with his clinical perspective on socket comfort, patient mobility, and the future of prosthetic care.
A major theme of the conversation is patient-managed comfort. For many prosthetic users, socket fit changes during the day because of residual limb volume variation. These changes can lead to discomfort, instability, pressure points, or the need to stop and adjust sock ply.
Alex discusses how giving users more control over fit adjustments can support comfort, confidence, and daily mobility. This is exactly the type of challenge Ethnocare aims to address with the Overlay.
Why Limb Volume Variation Matters
Limb volume variation happens when the size or shape of the residual limb changes throughout the day. This can be influenced by activity level, temperature, hydration, time of day, or other individual factors.
For transtibial and transfemoral amputees, even small volume changes can affect how the socket feels and functions. A socket that fits well in the morning may feel loose or uncomfortable later in the day. This can create challenges such as:
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Reduced socket stability
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Increased pressure or discomfort
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More frequent sock ply adjustments
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Difficulty maintaining comfort during activity
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Reduced confidence in daily mobility
Traditional prosthetic socks can help manage some volume changes, but they often require the user to remove the prosthesis, adjust ply, and refit the socket. For active users or busy clinical environments, this process can become frustrating.
Join Ethnocare at OTWorld 2026
Ethnocare will be at OTWorld 2026 in Leipzig, where we will continue the conversation around socket fit, patient-managed adjustability, and solutions for lower limb volume variation.
We will also host an exhibitor workshop:
The Solution for Lower Limb Volume Variation
Tuesday, May 19, 2026
11:00 AM to 11:45 AM
Room M4, Floor -1, Messehaus
Speaker: Marc-Antoine Malouin Lizotte
This workshop will focus on one of the most important challenges in lower limb prosthetic care: helping users manage residual limb volume changes inside the socket.
We will present how the Overlay TT and Overlay TF are designed to help users make fit adjustments without removing their prosthesis. The workshop will also highlight how adjustable air technology can support comfort, stability, and mobility throughout the day.
Overlay TT and TF: Patient-Managed Socket Fit Adjustment
The Overlay is an adjustable prosthetic insert designed to help manage volume changes inside the socket. It uses integrated air cells that can be inflated or deflated by the user, allowing them to adjust fit directly inside the prosthesis.
The goal is simple: help users manage socket fit changes more easily during the day.
Instead of relying only on prosthetic socks, the Overlay gives users another way to respond to limb volume variation. This can be especially valuable for people who experience frequent fit changes, discomfort, or instability.
The Overlay TT is designed for transtibial users, while the Overlay TF brings the same adjustable air technology to transfemoral users.
Overlay TF: Designed for More Transfemoral Users Than You May Think
Many clinicians are already familiar with the Overlay TT, but the Overlay TF offers an important opportunity for above-knee amputees as well.
With an expanded range of sizes and configurations, the Overlay TF may fit a larger group of transfemoral users than many clinicians first expect. It is designed to help manage daily volume changes, improve socket fit, and support comfort and stability throughout the day.
For transfemoral amputees, socket fit can have a major impact on mobility and confidence. When volume changes occur, users may experience movement inside the socket, pressure discomfort, or reduced control. The Overlay TF helps address this by allowing users to adjust fit through its air-based system.
The Overlay TT and TF are compatible with most existing liners and sockets. They can be used with different suspension methods, including distal fixation systems, suspension sleeves, passive vacuum systems, and active vacuum systems.
A Growing Conversation Around Patient-Managed Comfort
Across the prosthetics and orthotics field, there is growing interest in solutions that give users more control over their own comfort.
Patient-managed adjustability does not replace clinical expertise. Instead, it gives users a practical tool to manage daily changes between appointments and during real-life activities.
This approach can help support:
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Better socket fit throughout the day
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Improved comfort during daily activities
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Greater confidence in movement
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Easier management of residual limb volume changes
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A more responsive prosthetic experience
As Alex Dahin ten discussed on the podcast, innovation in prosthetics is not only about new materials or advanced engineering. It is also about understanding the daily challenges users face and creating practical solutions that fit into real life.
See Us at OTWorld
We look forward to meeting clinicians, distributors, partners, and prosthetic users at OTWorld 2026.
Whether you are interested in the Overlay TT, the Overlay TF, or the broader topic of limb volume variation in lower limb prosthetics, we would be happy to connect and continue the conversation.
Join our workshop, visit the Ethnocare team, and learn more about how patient-managed adjustability can help improve socket fit, comfort, and mobility.
Ready to Learn More?
To learn more about the Overlay TF or determine whether it may be a good fit, reach out to the Ethnocare team.
Clinicians and users can contact us at clinics@ethnocare.ca for questions, product information, or support.
If you are a prosthetic user, we recommend speaking with your prosthetist to see whether the Overlay may be appropriate for your socket and clinical needs.
