Runner Using Prosthetic Blade

Transfemoral Prosthesis – (Above Knee) System

Working in yard with transfemoral prosthesis, an above the knee prosthetic leg

The double-wall NPS socket system is designed to give amputees a transfemoral prosthesis that fits intimately and provides increased control and security. An added benefit is that the comfortable trim lines allow for a larger range of motion.

A silicone liner is rolled onto the residual limb. If the limb is relatively uniform in shape, an “off the shelf” will be used. For those residual limbs with bony prominences, neuromas, etc., a custom liner will be designed. All of our medical grade silicone liners are fabricated on-site in our liner manufacturing lab.

The second component of the system is the prosthetic sock. These socks are layered on top of the liner and act as a wick between the liner and the socket. Socks also accommodate for volume changes within the residual limb.

Next, the inner cup is slid over the prosthetic sock. This is where the POA system is different than others. A vacuum chamber laminated into the cup will allow even pressure to be distributed over the entire residua limb. A sealing sleeve, which is attached to the inner cup, is then rolled up to seal against the liner.

Lastly, the outer socket (with the knee and foot at-tached) is placed over the inner cup and the two pieces are locked together with a pin. Air is removed from the socket through a vacuum tube using a pump, creating elevated vacuum. This provides the intimate fit that re-sults in the feeling that the prosthesis is a part of you.

The Double Wall NPS Socket System

The double-wall NPS socket system in transfemoral prosthetics represents an innovative approach to improve comfort, stability, and functionality for individuals with above-knee amputations. Its narrow-profile design, dynamic alignment capabilities, shock absorption, and other features contribute to a more user-friendly and adaptable prosthetic solution.

Socket Design

The double-wall NPS socket system consists of two layers or walls. The inner socket is the primary load-bearing interface that comes in direct contact with the residual limb, while the outer socket provides structural support and reinforcement.

Narrow Profile Design

The term “narrow-profile” refers to the slim and contoured design of the socket. This design aims to reduce the overall bulkiness of the prosthetic limb, allowing for a more natural and aesthetically pleasing appearance. The narrow profile also facilitates better range of motion.

Improved Comfort

The double-wall construction helps distribute pressure more evenly across the residual limb. This can reduce pressure points and enhance overall comfort, allowing individuals to wear the prosthetic limb for more extended periods without discomfort

Dynamic Alignment

The double-wall NPS system allows for dynamic alignment adjustments, accommodating changes in the residual limb volume during daily activities or throughout the day. This adaptability contributes to better stability and functionality.

Schock Absorption

The POA double-wall NPS sockets incorporate materials with shock-absorbing properties in the design. This feature helps absorb impact forces during walking or other weight-bearing activities, improving comfort and reducing the strain on the residual limb.

Socket Liners

To enhance comfort and fit, the inner socket often includes a liner made of soft and cushioning materials. These liners can be customized to the individual’s anatomy and provide additional protection against friction and pressure.

Suction or Vacuum Systems

Our double-wall NPS socket systems integrate suction or vacuum technology. This feature creates a secure and airtight seal between the socket and the residual limb, improving suspension and reducing the likelihood of slippage.

Lightweight Materials

The use of lightweight and durable materials in the construction of the double-wall NPS socket system contributes to the overall efficiency of the prosthetic limb. This is particularly important for reducing the energy expenditure required during walking and other activities.

Adjustability and Modularity

The double-wall NPS system often allows for modular components and adjustments, enabling prosthetists to fine-tune the socket to meet the specific needs and preferences of the individual user.

Frequently Asked Questions About Transfemoral Prosthetics

A Transfemoral Prosthesis is a prosthetic limb designed for individuals who have undergone amputation above the knee. It replaces the missing limb and aids in restoring mobility.

The prosthetic limb consists of a socket, knee joint, pylon, and foot. The socket fits securely onto the residual limb, and the knee joint allows for natural movement during walking, providing stability and support.

Benefits include improved mobility, enhanced stability, increased independence, and the ability to engage in various physical activities.