What is the main disadvantage of using a Liner + Lanyard for TF prosthetics?

The primary disadvantage of using a Liner + Lanyard for transfemoral (TF) prosthetics is the phenomenon known as pistoning or milking of tissue. This issue arises because the lanyard system, which is designed to secure the prosthetic limb to the residual limb, may not offer a completely stable fit. As users walk or move, the prosthetic can shift relative to the residual limb, leading to the displacement of tissues. This can cause discomfort and even skin damage due to friction and pressure in certain areas.

Pistoning can be particularly problematic for individuals who engage in activities that involve a lot of movement or require a snug fit for comfort and functionality. It's crucial that the prosthetic maintains a close connection to the residual limb to prevent any unnecessary movement that could result in skin irritation or breakdown.

While other disadvantages listed may also pose challenges in specific contexts, they do not encapsulate the critical movement-related issues that arise from a Liner + Lanyard configuration. Hence, understanding the implications of pistoning is vital for ensuring the safety and comfort of individuals using transfemoral prosthetics.