Transfemoral Prosthesis – (Above Knee) System


Prosthetic Systems at Prosthetic & Orthotic Associates

Transfemoral Prosthesis – (Above Knee) System

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.