Abstract: Studying stress and strain trends in the femur and
recognizing femur failure mechanism is very important for
preventing hip fracture in the elderly. The aim of this study was to
identify high stress and strain regions in the femur during normal
walking and falling to find the mechanical behavior and failure
mechanism of the femur. We developed a finite element model of the
femur from the subject’s quantitative computed tomography (QCT)
image and used it to identify potentially high stress and strain regions
during the single-leg stance and the sideways fall. It was found that
fracture may initiate from the superior region of femoral neck and
propagate to the inferior region during a high impact force such as
sideways fall. The results of this study showed that the femur bone is
more sensitive to strain than stress which indicates the effect of
strain, in addition to effect of stress, should be considered for failure
analysis.
Abstract: Finite element method was applied to model damage
development in the femoral neck during a sideways fall. The femoral
failure was simulated using the maximum principal strain criterion.
The evolution of damage was consistent with previous studies. It was
initiated by compressive failure at the junction of the superior aspect
of the femoral neck and the greater trochanter. It was followed by
tensile failure that occurred at the inferior aspect of the femoral neck
before a complete transcervical fracture was observed. The estimated
failure line was less than 50° from the horizontal plane (Pauwels type
II).