Computational Analysis of Strength and Fracture Location of Different Types of Femurs under Falling Condition using CT-Image based Finite Element Method

Abstract

Sideways falling has been considered as a leading cause of hip fracture in elderly people with a high risk of morbidity and mortality. Therefore, early investigation of optimum femoral strength and fracture location of people at greatest risk can be clinically very useful for the preventive measures. It is also considered that some typical femoral diseases such as osteoarthritis (OA) and avascular necrosis (AVN) could affect the strength and fracture behaviour of the femurs. In this study, 130 computational femoral models were constructed using CT images of 73 patients. Then, CT image based finite element method combined with the damage mechanics analysis was applied to predict the fracture load as the femoral strength and the fracture location of the femoral models. The computational results exhibited that the fracture load tended to increase with increase of the volumetric bone mineral density estimated in the femoral head and neck region in all the three types of models. The bone fracture behaviour was expressed as expressed as the distribution of failure elements in the head and neck region. Under fall loading, the bone fracture mainly took place in the greater trochanter region for all types of femoral model. In addition, a combination of the greater trochanter and multifarious neck fracture was also observed in all the models. A combination of greater trochanter and intertrochanteric fracture was also observed in the AVN group.