Sockets and Liners
Prosthetic sockets, liners and suspension systems; fit and care.
What are sockets and liners?
The socket and liner are the two most fundamental components of a lower limb prosthesis. The socket is the custom-made shell that creates the connection between the residual limb and the rest of the prosthesis. The liner is a flexible, cushioned protective interface worn over the residual limb and positioned between the skin and the socket.
Working together, these two components allow the prosthesis to be worn securely, comfortably and in a balanced way. While the liner reduces friction and movement on the skin, the socket distributes body weight evenly and helps keep the prosthesis in place during walking.
The right socket-liner combination is determined according to the type of amputation, the shape and length of the residual limb, skin structure and the person's daily activity level. This choice is usually finalized with a prosthetics specialist at the end of a trial and assessment process.
Socket, liner and components
Liners
Silicone/TPE liner types and care.
Learn moreActive Vacuum Socket
Negative-pressure suspension.
Learn morePassive Vacuum Socket
Passive vacuum suspension.
Learn morePin-Lock Socket
Mechanically locking suspension.
Learn moreAdjustable Socket
An adaptable socket approach.
Learn moreConnecting Components
Adapters and pylon.
Learn moreThe function of a prosthetic socket
The socket forms the critical connection between the residual limb and the prosthesis and is usually custom-made from lightweight, durable materials (such as carbon, silicone and lamination resins). A well-fitting socket directly affects both comfort and walking safety. The main functions of the socket can be summarized as follows:
- Supports load transfer and ensures that axial forces generated during walking are distributed evenly.
- Absorbs horizontal forces, preventing the residual limb from moving back and forth inside the socket, and improves balance.
- Provides a continuous and firm connection between the residual limb and the socket during the swing phase.
How does a liner work?
A liner can be thought of as a kind of protective sleeve worn over the residual limb; it is rolled onto the limb like a thin sock and creates a soft cushion between the skin and the hard socket surface. This reduces friction and pressure on the skin and makes the grip of the prosthesis more comfortable. The liner also helps protect sensitive, bony or scarred areas of the residual limb.
- Reduces movement and friction between the skin and the socket.
- Provides a comfortable and secure grip on the residual limb.
- Protects sensitive areas by distributing pressure more evenly.
Types of liner materials
Liners are made from different materials, and each type of material offers different properties for specific needs. The suitable liner material is selected according to skin structure, the condition of the residual limb and the suspension system used. The most common liner materials are:
- Silicone liners: Provide high stability and good adhesion, are durable and are usually easy to clean. They help stabilize soft tissue.
- Copolymer liners: Soft materials with high elasticity; they can be thermally shaped and may have nourishing properties suitable for dry skin.
- Polyurethane liners: Thanks to their flow properties, they distribute pressure evenly; they help cushion impact on sensitive, bony or scarred residual limbs.
Suspension systems
The liner and suspension system determine how the connection between the residual limb and the socket is maintained and keep the socket from slipping off the limb during walking. Suspension systems are usually designed to work with specific liners and typically operate on one of two basic principles: through negative pressure (vacuum/suction seal) or through a mechanical retention system (for example, a pin connection). The system suited to the person's needs is mostly determined by the shape and length of the residual limb. Vacuum- or suction-based systems may additionally require a sealing sleeve.
Points to consider in liner and skin care
Regular care of the liner and the skin of the residual limb is important for maintaining comfort and preventing skin problems. Proper care helps reduce pressure points and friction-related irritation. General recommendations are:
- The liner should generally be cleaned after each use, at least once a day; a neutral and suitable cleaning product should be preferred.
- A suitable drying method should be used so that the liner keeps its shape; radiators or direct sunlight should be avoided.
- The skin should be cleaned with mild cleansers and, when needed, supported with moisturizing care products.
- If signs such as red lines, increased sweating or irritation persist, a prosthetics specialist should be consulted; these conditions may be related to liner fit or material selection.
Application process
Physician's prescription / report
The process starts with a prescription or medical report issued by a specialist physician. No application is made without a prescription or report.
Assessment and measurement
The person's condition is assessed; measurements are taken for custom-made production and a service plan is prepared.
Production and fitting
The custom-made prosthesis or orthosis is produced; fit and alignment are adjusted during the fitting stage.
Application and user training
The device is applied; use, cleaning and care are explained.
Follow-up
Follow-up is provided for check-ups, maintenance and repair after the application.
Related informational content
Types of Prosthetic Sockets
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What Are Active Vacuum Socket Systems and How Do They Work
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How Do Passive Vacuum Socket Systems Work?
ReadPin-Lock (Shuttle Lock) Socket Systems
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Adjustable Socket Systems and Early Rehabilitation
ReadApplications are carried out in line with a specialist physician's prescription or medical report, at our licensed center addresses. This content is for information only; please consult your physician for diagnosis and treatment.