SCANNING ACOUSTIC MICROSCOPY FOR MICROMEASUREMENT OF ELASTOMECHANICAL BONE PROPERTIES- COMPARISON WITH NANOINDENTATION RESULTS

摘要

Until today it remained a problem to detect mechanical properties of bone. Bone is a tissue highly adopted to its load-bearing function and may change its properties in dependance on the present mechanical need. It is kown that bone mass is changing with age and the amnount of bone loss is correlated with the incidence of fracture in osteoporosis. A decrease in bone mineral density of one SD increases the fracture risk by more than two times. But there is any evidence that exist factors influencing the skeletal fragility independent of bone mass summarized in clinical terms as bone quality. It comprehends mechanical properties of the material bone itself such as elasticity and strain resistance. Only little is known on these intrinsic elastic properties. The high anisotropy of bone, the porosity and function-related structures make it extremly difficult to measure and describe its mechanical properties in detail with testing procedures commonly used in materials science such as bending test or torsion test. Acoustic investigation of bone can deliver informations of more complex and detailed nature and by using a scanning acoustic microscope of the last generation, with sufficently high resolution.