Hip Model for Osteonecrosis - Computational Biomechanics of the Musculoskeletal System - page 113

10 Hip Model for Osteonecrosis
Duo Wai-Chi Wong, Zhihui Pang, Jia Yu,
Aaron Kam-Lun Leung, and Ming Zhang
ContentS
Summary ........................................................................................................................................ 113
10.1 Introduction .......................................................................................................................... 114
10.1.1 Background ............................................................................................................... 114
10.1.2 Prevalence ................................................................................................................. 114
10.1.3 Etiology and Diagnosis ............................................................................................. 115
10.1.4 Natural History ......................................................................................................... 115
10.1.5 Review of Biomechanical Studies ............................................................................ 116
10.1.6 Investigation of the Pathomechanism ....................................................................... 117
10.2 Model Development .............................................................................................................. 118
10.2.1 Geometry Acquisition ............................................................................................... 118
10.2.2 Material Properties ................................................................................................... 118
10.2.3 Boundary Conditions ................................................................................................ 118
10.3 Applications .......................................................................................................................... 118
10.3.1 Trabecular Yield ....................................................................................................... 118
10.3.2 Load Transfer Alteration .......................................................................................... 118
10.3.3 Strain Energy Density Ratio ..................................................................................... 119
Acknowledgments .......................................................................................................................... 121
References ...................................................................................................................................... 121
Summary
Osteonecrosis of the femoral head (ONFH) is one of the common pathologies of the hip joint
(Hernigou and Beaujean 2002). Femoral head collapse is the most devastating stage of ONFH.
The surgical failure rate of post-collapse patients remains very high. Nearly all femoral head col-
lapse patients require additional surgery or total hip replacement (Hernigou and Beaujean 2002;
Lieberman, Conduah, and Urist 2004; Wirtz, Rohrig, and Neuss 2003; Yoon et al. 2001). Joint-
preserving modalities are not adequate to prevent and delay the deterioration of the collapsed hip
(Lieberman et al. 2012).
Joint-preserving surgical treatment during the early stages of ONFH is often recommended (Mont
et al. 2010), including deep compression, vascularized bone grafting, and tantalum rod insertion.
Though satisfactory outcomes have been reported, studies have been inconsistent in their reporting
of patient satisfaction and success (Chen et al. 2009; Fairbank et al. 1995; Markel et al. 1996).
In this section, the biomechanical nature of ONFH, such as lesion size, angle, material, and weight-
bearing characteristics, and its associated operation, is investigated (Yoo et al. 2008; Mont et al. 1998;
Yoshida et al. 2006; Brown, Way, and Ferguson 1981). Computational simulations were also undertaken
on an osteonecrotic hip (Brown, Mutschler, and Ferguson 1982; Daniel et al. 2006; Yang et al. 2002).
Nevertheless, the optimal modality and when to carry out the surgery for ONFH remain troubling
points for clinicians (Hungerford and Jones 2004; Lieberman et al. 2003). A platform must be estab-
lished to systematically evaluate the pathomechanism and intervention strategies for ONFH.
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