Osteoporosis is a metabolic disease of the bone responsible for a loss of bone resistance and an increase in fracture risk. World Health Organization (WHO) estimations are about 6.3 millions of femoral neck fractures in the world by 2050. These estimations make osteoporosis a real problem in term of public health. Knowledge in biological tissues mechanical behaviour and its evolution with age are important for the design of diagnosis and therapeutic tools. From the mechanical aspect, bone resistance is dependent on bone density, bone architecture and bone tissue quality. If the importance of bone density and bone architecture has been well explored, the bone tissue quality still remains unstudied because of the lack of biomechanical tools suitable for testing bone at this microscopic dimension. Therefore the goal of this study is to estimate the osteoporotic cancellous bone tissue mechanical behaviour at its microscopic scale, using an approach coupling mechanical assays and digital reconstruction. The experimental study is based on cancellous bone tissue extracted from human femoral head. Forty 8mm diameters bone cylinders have been removed from femoral head explanted after a femoral neck fracture treated by arthroplasty. These cylinders have been submitted to a digitally controlled compressive trial. Before and after the trials, microscanner analyses with an 8 μm spatial resolution have been realized in order to determine the micro structural parameters. The cylinders have been rebuilt with the digital model-building in order to estimate the mechanical behaviour and the bone quality.Introduction
Materials and methods
