Loading Applied on Osseointegrated Implant by Transtibial Bone-Anchored Prostheses During Daily Activities

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, 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 spatio-temporal characteristics, loading boundaries, local extremum and impulse. Results. The absolute maximum load extracted from 319 gait cycles 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 to differentiate transtibial bone-anchored prostheses was achievable when relying on tri-axial direct measurements, recording a range of daily activities in addition of walking and considering at least nine loading extremum. Conclusions: Prosthetic care providers could use this characterization for evidence-based fitting of components to growing population of individuals with transtibial amputation fitted with osseointegrated implant worldwide.