User preference in the personalized control of an ankle prosthesis: a case study.

Only three participants were studied, and all were high-functioning K3 or higher users of passive prostheses, so the findings may not apply to less mobile amputees or people new to prostheses. They had only one three-hour familiarization session, so preference may have reflected unfamiliarity with active ankle assistance rather than a stable long-term choice. The sample size was too small for statistical analysis, so the results are descriptive observations. Walking speed was fixed, and previous work suggests speed can influence preferred magnitude, so faster or slower walking might change the settings chosen. Ankle torque was estimated from motor position and ankle angle, not directly controlled, so torque comparisons across participants and trials are uncertain. The knee was kept overextended during stance, so the study tested ankle push-off only, not full knee-ankle control. Participants did not explore the full grid, and high assistance magnitudes were rarely tested, so the preferred area is imprecise.

Do not conclude that personalized powered ankle prosthesis control improves mobility or that muscle activity determines user preference. Three high-functioning participants, one familiarization session, fixed treadmill speed, and no statistical analysis mean these are descriptive observations, and long-term passive prosthesis use may have shaped their choices.