title: Risk of fracture in elderly patients: a new predictive index based on bone mineral density and finite element analysis.
abstract: Hip fracture is more and more frequent in elderly population. For this reason, an increasing attention has been focused on the development of a non-invasive method to predict femoral neck fracture. A conventional approach to fracture diagnosis is the measurement of bone mass by dual-energy X-ray absorptiometry in some regions of interest. The aim of this work is to assess a method that accounts for the structural details of the bone providing a more direct determination of strength properties, and improving the diagnostic power of the current densitometric systems. A 2D finite element model of the proximal femur is derived from dual-energy X-ray absorptiometry data. Initially, the method is validated in vitro using a replica of the human femur. The predicted results are compared to strain-gauge measurements and to a 3D finite element model, with good agreement being observed. Then, an in vivo preliminary study on a limited group of patients is carried out. The loading condition that simulates a fall to the side onto the greater trochanter from standing height is employed. All simulations show a peak strain at the femoral neck region with a strain distribution typical of a fall on the side. The proposed method seems to supply a useful tool for the in vivo analysis of the risk of hip fracture.
authors.affiliation: Laboratorio Tecnologia dei Materiali, Istituti Ortopedici Rizzoli, Bologna, Italy. testi@tecno.ior.it
authors.forename: D
authors.initials: D
authors.lastname: Testi
authors.forename: M
authors.initials: M
authors.lastname: Viceconti
authors.forename: F
authors.initials: F
authors.lastname: Baruffaldi
authors.forename: A
authors.initials: A
authors.lastname: Cappello
mesh_terms: D000368:Aged; D015519:Bone Density; D003198:Computer Simulation; D005265:Femoral Neck Fractures / Q000503:physiopathology*; D020342:Finite Element Analysis; D006801:Humans; D008954:Models, Biological; D011237:Predictive Value of Tests; D012307:Risk Factors