Loading applied on osseointegrated implant by transtibial bone-anchored prostheses during daily activities: Preliminary characterization of prosthetic feet.

Abstract

ABSTRACT Introduction This case series study laid out principles for characterization of loading profile applied on osseointegrated implant by transtibial bone-anchored prostheses fitted with various feet while presenting benchmark loading data. Materials and Methods Three individuals walked and ascended and descended stairs and ramps with instrumented prostheses fitted with a load cell as well as usual and anthropomorphic feet successively. The characterization of the loading profile involved the comparison of 100 variables including spatiotemporal characteristics, loading boundaries, local extremum, and impulse. Results The absolute maximum load extracted from 319 gait cycles (GCs) with both prostheses across all activities was 48 %BW, 17 %BW, and 112 %BW for the forces as well as 2 %BWm, 13 %BWm, and 1 %BWm for the moments on and around the anteroposterior, mediolateral, and long axes of the implant, respectively. Discussion New evidence presented here indicated that a specific and comprehensive loading characterization capable of differentiating transtibial bone-anchored prostheses was achievable when relying on triaxial direct measurements, recording a range of daily activities in addition to walking, and considering at least nine loading extremum. Conclusions Prosthetic care providers could use this characterization for evidence-based fitting of components to the growing population of individuals with transtibial amputation fitted with osseointegrated implants worldwide.