FE Analysis of Contact between Residual Limb and Socket during Simulation of Amputee Motion

Abstract

The contact pressure at the socket-residual limb interface is the most important parameter to evaluate comfort of leg prosthesis. Experimental works analyzed this parameter for typical postures and during walking of an amputee; but experimental tests require a real prototype of the socket equipped with transducers. To optimize socket design, this work presents a virtual approach based on a digital avatar of the patient wearing lower limb prosthesis. Our approach considers the integration of two different types of simulation: the first one concerns the multi-body gait analysis, the second one the pressure evaluation at the socket-residual limb interface with FE analyses. The paper describes the model used, the simulation tools adopted and their integration. Finally the case study related to patient walking on flat floor is described

Analysis of compression/release stabilized transfemoral prosthetic socket by finite element modelling method

“…Colombo et al [30] reported a 200 kPa maximum contact pressure on the transfemoral residual limb surface which is slightly smaller than present findings. However, they evaluated the walking condition with several times of the body weight applied at the hip joint.…”

Combining Freehand Ultrasound-Based Indentation and Inverse Finite Element Modeling for the Identification of Hyperelastic Material Properties of Thigh Soft Tissues

“…The current study presents a method to combine inverse FEM and freehand ultrasound-based indentation for the identification of the passive material properties of the soft tissues of the thigh. Factually, most of the studies dealing with FEM of the thigh do not personalise the material properties of soft tissues, and would rather turn to values from literature [1,[6][7][8]10]. Indeed, very few studies developed the necessary process to estimate the personalised mechanical behaviour of soft tissues, especially when large soft tissues thicknesses are involved, like in the thigh area.…”

“…This interface is critical in order to ensure an optimal tradeoff between load transmission and both comfort and the prevention of soft tissues injuries. This is the reason why a particular attention has been paid to the mechanical behaviour of soft tissues under contact loadings in the last decade [1][2][3]. One way to evaluate loadings at the interface is to design subject specific Finite Element (FE) models [2,[4][5][6].…”