RecruitingDevice studyQuantifying Bone and Skin Movement in the Residual Limb of Individuals With Transtibial Amputation Using Dynamic Stereo X-RayIndividuals with lower extremity amputation are often challenged by complications that arise from poor prosthetic fit, including movement of the residual limb in the socket, known as pistoning. Pistoning can lead to gait instability, skin problems, and pain. Different prosthetic suspension systems have been developed to decrease this motion, including elevated vacuum suspension, which utilizes a pump to draw air from the socket. However, scientific analyses to understand the movement between the limb and socket have yet to be performed with a high level of accuracy. This study will use a state-of-the art imaging technique, known as dynamic stereo x-ray, to quantify the 3D movement of the residual limb in the socket. It is hypothesized that dynamic stereo x-ray will be a sensitive method to measure differences in residual limb movement between 2 different socket suspension techniques: suction and elevated vacuum suspension. This information is critical for advancing prosthetic treatments to reduce secondary conditions and degenerative changes that result from poor prosthetic fit.