2006 年 72 巻 714 号 p. 255-262
Osteoporosis is serious medical issue to be solved in aging society. There are no less than 10 million osteoporosis patients in Japan. Osteoporosis causes frequently bone compressive fracture in lower vertebrae. It is important to estimate a fracture risk and provide adequate treatment in early stage of osteoporosis. However, bone mineral density is quantified by Dual Energy X-ray Absorptiometry (DEXA) in current clinical diagnosis of osteoporosis, mechanical factor such as bone strength, which is essential to evaluate bone fracture risk, is not considered. In this study, we evaluated the fracture risk of osteoporosis patient's vertebrae by patient-specific finite-element (FE) analysis in static loading condition. We used “Mechanical Finder (RCCM, Co., LTD.)” that was computer software for bone strength analysis considering individual bone shape and density distribution based on Computer Tomography (CT) images. Furthermore, we also tried to evaluate the fracture risk by dynamic FE analysis to reflect more severe loading conditions. Availability of dynamic analysis was investigated in comparison with the results of the static analysis. At last, efficiency of proposed mechanical evaluation method for vertebral osteoporosis was discussed.