Paper Title
FE Model for Biomechanical Analysis and Prediction of Older Women Breast Deformation

Abstract
The purpose of this study is to quantify the breast deformation and further to construct a kind of convenient, noninvasive and reliable finite element model (FEM) for the biomechanical analysis of the elderly breast. This method realizes the idea in using non-linear multi-component FEM to predict breast movement and provide hint of deformation in order to predict potential breast pains or injuries resulting from yoga exercise, for instance, Warrior II. In this paper, it initially was used the motion capture system to quantify the selected markers motions of breasts. A comprehensive musculoskeletal FEM is presented to simulate the breast (C cup size) deformations of an elderly woman through a combination of contraction and extension from the pectoralis major muscle (PMM) during arm abduction from 30° to 90°. From the results collected by the motion capture system, it was found that the selected distance in the upper outer quarter has almost four times change ratio larger than that in the upper inner quarter. By validating with motion capture data, this study highlights the customized material coefficients of PMM, in which Young’s modulus of clavicular and sternocostal portion was ascertained as 0.1 and 0.08 MPa, respectively. In comparison to conventional FEMs for breast, the realistic one presented here features the musculoskeletal system as well as reveals the synergistic relationship between the breast and PMM, thereby providing a promising basis for the design of the sport bras in an ergonomic way. Index Terms - Breast Deformation, Older Women, Finite Element Model, Motion Capture.