Overview

The goal of this clinical trial is to 1) demonstrate the feasibility of monitoring pressure, temperature, and lactic acid density of sweat inside the prosthetic socket, and 2) verify the relationship between mechanical pressure and Lactic acid density of sweat for lower limb amputees among transtibial amputees. The main questions it aims to answer are:

• Is it feasible to reliably monitor pressure, temperature, and lactic acid density inside the prosthetic sockets simultaneously?
• Will the lactic acid density increase with higher pressure exposure? The participants are expected to wear the newly developed E-SWEAT system on their residual limb and are exposed to two activities, walk which generate mechanical load on the residual limb, and a yoga post - birddog, which does not generate mechanical loading on the residual limb. The E-SWEAT will measure pressure, temperature, and lactic acid density of sweat during these tasks.

Eligibility

Inclusion Criteria:

• Be 18 years or older
• Have a unilateral lower limb amputee (below the knee). The tibial length on the residual limb must be greater than half of the length of the tibial on the unaffected side
• Have an amputation that occurred over 2 years ago
• Have at least 1 year of experience using your prosthetic leg
• Have used the current socket for at least 6 months without a significant skin issue or major modification
• Be able to comfortably walk 6 mins (with prosthetic legs) without pausing to rest
• Be willing to come to North Carolina State University's Centennial Campus to participate in research and be photographed while doing research activities

Exclusion Criteria:

• Have a cognitive or visual impairment that affects the participant's ability to provide informed consent or to follow simple instructions during the experiments
• Have any neuropathy observed on the residual limb
• Experience numbness, tingling, muscle weakness, and/or pain in your residual limb
• Weigh more than 300lbs
• Do not want to take photos
• Are pregnant or plan to get pregnant
• Are allergic to latex, which is often contained in medical tapes.
• If you are using medication to control sweat on your residual limb, and your medical provider does not think that it is OK to avoid these medications for 48 hours.