The Relationship Between Loading Conditions and Fracture Patterns of the Proximal Femur

Abstract

In an attempt to test the hypothesis of spontaneous hip fracture, seven pairs of femurs, with ages ranging from 59 to 90, were tested under two loading conditions designed to simulate muscular contraction. Simulated iliopsoas contraction produced femoral neck fractures at an average normalized ultimate load of 5.2 +/- 0.8 times body weight. Simulated gluteus medius contraction produced sub-/inter-trochanteric fractures at an average normalized ultimate load of 4.1 +/- 0.6 times body weight. The average ultimate load for all specimens was 3040 +/- 720 N. Fracture patterns produced by both loading conditions were clinically relevant. The results from this study suggest that abnormal contraction produced by major rotator muscles could induce hip fracture.

A quasi-brittle continuum damage finite element model of the human proximal femur based on element deletion

“…Several studies showed that bone exhibits a quasi-brittle material behavior [5,14,16,[32][33][34]62] or brittle behavior [31,43,68,88] depending mainly on the deformation rate applied and the bone properties. Therefore, more suitable physical models are still lacking to describe the brittle to quasi-brittle fracture behavior of human femur.…”

Are spontaneous fractures possible? An example of clinical application for personalised, multiscale neuro-musculo-skeletal modelling

“…But it has been suggested that when neuromotor control is sub-optimal, the forces transferred to the skeleton during normal daily activities can considerably increase , thus inducing overloading. Moreover, (Yang et al, 1996) developed an in vitro simulation to determine a possible biomechanical background for spontaneous hip fractures, concluding that abnormal muscle contraction of the rotator muscles could induce hip fracture. If these conjectures are true, then truly spontaneous fracture could be possible, at least in principle.…”

Cadaveric Femoral Fractures in a Fall on the Hip Configuration

“…Regression analysis was also used to examine the correlation between fracture forces and geometric parameters. Finally, using post-fracture CT scans, we classified the femoral fractures into subcapital, transcervical, intertrochanteric and pertrochanteric based on Müller AO Classification of Fractures-Long Bones [15]. We used ANOVA to compare the fracture types of femora with different aBMD.…”