Bilateral transtibial amputation presents a complex biomechanical condition in which the loss of biological ankle function and reduced sensory feedback can compromise walking stability. This case study aimed to experimentally evaluate gait stability in a bilateral transtibial prosthesis user under controlled sensory and mechanical walking conditions using a portable G-Walk inertial measurement system. The novelty of this study lies in the use of a structured three-factor experimental protocol that systematically combined visual input, arm posture, and surface type across twelve walking conditions to assess walk quality, propulsion, propulsion symmetry, and pelvic symmetry indices. The participant was a 31-year-old bilateral transtibial prosthesis user with a K3 mobility level using bilateral EchelonVAC multi-axis carbon feet. The results showed clear variations in stability-related gait parameters across the tested conditions. The most favorable gait pattern was observed during walking on a solid surface with eyes open and natural arm swing, whereas the least favorable pattern occurred during walking on a foam surface with eyes closed and hands on hips. Overall, visual deprivation and compliant surface walking appeared to have the strongest destabilizing influence on gait stability. These findings provide useful biomechanical insight into gait stability challenges in bilateral transtibial prosthesis use and may support future rehabilitation planning, prosthetic evaluation, and stability assessment under sensory-challenging walking conditions.
Jaian et al. (Thu,) studied this question.