The Effect of Boundary Condition on the Biomechanics of a Human Pelvic Joint Under an Axial Compressive Load: A Three-Dimensional Finite Element Model

Abstract

The finite element (FE) model of the pelvic joint is helpful for clinical diagnosis and treatment of pelvic injuries. However, the effect of an FE model boundary condition on the biomechanical behavior of a pelvic joint has not been well studied. The objective of this study was to study the effect of boundary condition on the pelvic biomechanics predictions. A 3D FE model of a pelvis using subject-specific estimates of intact bone structures, main ligaments and bone material anisotropy by computed tomography (CT) gray value was developed and validated by bone surface strains obtained from rosette strain gauges in an in vitro pelvic experiment. Then three FE pelvic models were constructed to analyze the effect of boundary condition, corresponding to an intact pelvic joint, a pelvic joint without sacroiliac ligaments and a pelvic joint without proximal femurs, respectively. Vertical load was applied to the same pelvis with a fixed prosthetic femoral stem and the same load was simulated in the FE model. A strong correlation coefficient (R(2)=0.9657) was calculated, which indicated a strong correlation between the FE analysis and experimental results. The effect of boundary condition changes on the biomechanical response depended on the anatomical location and structure of the pelvic joint. It was found that acetabulum fixed in all directions with the femur removed can increase the stress distribution on the acetabular inner plate (approximately double the original values) and decrease that on the superior of pubis (from 7 MPa to 0.6 MPa). Taking sacrum and ilium as a whole, instead of sacroiliac and iliolumber ligaments, can influence the stress distribution on ilium and pubis bone vastly. These findings suggest pelvic biomechanics is very dependent on the boundary condition in the FE model.

Effect of screw position on load transfer in lumbar pedicle screws: a non-idealized finite element analysis

“…The use of surface strain to validate finite element models in biomechanics is not uncommon,(Hao et al 2011) and analyses of surface strain in the spine using rosette strain gauges have also been reported. (Hongo, Abe, Shimada, Murai, Ishikawa and Sato 1999, Kayanja et al 2004, Kayanja et al 2005, Szivek et al 2002) Calculations of stress from strain recorded by a rosette strain gauge are less common in spinal biomechanics, but have been reported in a study involving the femur.…”

In-silico pelvis and sacroiliac joint motion—A review on published research using numerical analyses

“…Regarding material properties, a majority of models were stated as being linear elastic (Tables 1a,1b,1c), and only three models were nonlinear (Anderson et al, 2004;Eichenseer et al, 2011;Lee et al, 2017). Isotropic material properties form the majority of the existing modeling approaches, whereas only four studies used non-isotropic material parameters (Anderson et al, 2004;Hao et al, 2011;Hu et al, 2017;Shi et al, 2014). No material model was given in the remaining models.…”

“…Virtual computational models of the human pelvis have evolved as highly useful tools to assess load distribution under healthy conditions, as well as pathologically altered biomechanics (Anderson et al, 2004;Böhme et al, 2014;Bruna-Rosso et al, 2016;Eichenseer et al, 2011;Hammer et al, 2013;Hao et al, 2011;Kim et al, 2014;Phillips et al, 2007b;Shi et al, 2014;Watson et al, 2017), and to evaluate the effects of both non-surgical (Sichting et al, 2014) and surgical treatment (Böhme et al, 2012;García et al, 2000;Kurz et al, 2017). The finite elements (FE) method is commonly utilized for this purpose.…”

Finite element simulation of articular contact mechanics with quadratic tetrahedral elements

“…Although quadratic tetrahedral elements have been investigated as alternatives to HEX8 elements (e.g., (Cifuentes and Kalbag, 1992; Tadepalli et al, 2011; Weingarten, 1994)), none of these studies investigated their application for simulation of articular contact analyses. The 10-node tetrahedron (TET10) has seen some limited use for contact mechanics (Bunbar et al, 2001; Hao et al, 2011; Tadepalli et al, 2011; Wan et al, 2013; Yang and Spilker, 2006). To our knowledge the 15-node tetrahedron (TET15) has never been used in computational biomechanics and it has seen very limited use in nonlinear computational solid mechanics at all (Danielson, 2014), although it has been used in the fluid mechanics community (Bertrand et al, 1992).…”