Knee Implant Model - Computational Biomechanics of the Musculoskeletal System - page 98

60-degree flexion. Conversely, the change at the AF was relative drastic. The compressive stress
increased from about 0.31 MPa at full extension to 3.18 MPa at 60-degree flexion, which is about a
10-fold increase.
The stiffness of the trabecular bone was parameterized and divided into the AF, PR, and SR
regions (Figure 8.5). Around the AF region, the predicted compressive stress generally increased

6

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Trabecular stiffness (MPa)

FIgure 8.5 Predicted compressive principal stress of the AF (top), PR (center), and SR (bottom) regions
with varying trabecular stiffness. The constitutive equation of yielding stress (dotted line) was suggested by
Burgers et al. (2008).