Analysis of trans tibial prosthetic socket materials using finite element method

Prasanna Kumar Lenka, Amit Roy Choudhury
DOI: 10.4236/jbise.2011.412094                

Abstract

The objective of this work was to analyze in a parametric study for optimum design solution of prosthetic socket material by finite element method. A realistic three-dimensional finite element model of the PTB socket was developed to find out the stress distribution pattern under physiologically relevant loading condition during normal walking. The CAD model of the rectified socket was collected from a CMET 250 non-tactile high accuracy (0.06 mm) white light scanner and analyses were carried out using finite element Method in ANSYS®. All structural materials used in the analysis were assumed to be linearly elastic, homogeneous and isotropic. Different materials were used for socket and only polypropylene was used for socket adopter. Analysis was prepared at 2 mm, 3 mm, 4 mm, 5 mm & 6 mm thickness of socket in different materials commonly used in developing countries. The bottom line of socket was made to zero displacement constraints and vertical loads in relation to stance phase of gait cycle were applied under static condition at the patella tendon brim. The 3 mm laminated composite sockets was found to be optimum in terms of strength, weight and factor of safety.

Keywords

Finite Element Method; Transtibial Prosthesis; Socket; Polymer

Conflicts of Interest

The authors declare no conflicts of interest.

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