Comparison between two different fe modelling approaches to account for body weight in subject-specific socket design

Biomechanical interfaces can be improved by virtual prototyping, allowing an accurate prediction and optimization of subject-specific socket-skin pressure distribution. In this work we present a comparison between two different modelling approaches for socket prototyping of a transtibial amputee. The method consists on the implementation of a finite element model to design socket geometry from subject morphology (lower extremity bones, tendon and skin), soft tissue and patellar tendon mechanical properties, liner with uniform pressure and external load. Load is applied in two stages, first as non-uniform fitting pressure on the equilibrium geometry for morphing the socket; and second as floor reaction on distal nodes corresponding to body weight load (subject standing in one leg). Final skin surface pressure results are compared with results using the piston/displacement approach described previously.