A Novel 'Test-Drive' Strategy for Prosthetic Foot Prescription Using a Robotic Prosthetic Foot Emulator

Selecting an optimal prosthetic foot is vital to maximizing mobility and achieving functional goals in people with lower limb loss. However, patients do not generally have an opportunity to provide experiential input to the foot selection process. This study aimed to assess an innovative 'test-drive' strategy for foot selection. Sixty-eight individuals with transtibial amputation each trialed three commercial prosthetic feet and three corresponding emulated feet using a robotic foot emulator capable of switching between feet via a software interface during walking on level, inclined, and stair treadmills in the laboratory. Participants then wore each commercial foot for consecutive two-week community trials. All foot conditions were randomized and participant-blinded. Foot preference was measured on a 0-10 scale. Following each community trial, participants also completed self-reported and performance-based measures. Linear mixed-effects regression was used to assess associations between outcomes. Initial foot preference scores from trials with emulated feet correlated with preference scores after community trials with the corresponding commercial feet (p<.001) and with Trinity Amputation and Prosthesis Experience Scales–Functional Satisfaction score (p=.036), but not with Two Minute Walk Test, Prosthetic Limb Users Survey of Mobility, or Activity-Balance Confidence scores. The most-preferred foot after the after the in-lab trial of the emulated foot matched the most-preferred foot after the community trial of the corresponding commercial foot for 48/68 participants. These results suggest that a patient-centered 'test-drive' strategy using a prosthetic foot emulator could potentially enhance prosthetic foot prescription and lead to improved patient satisfaction outcomes in people with lower limb amputation.