THE MECHANICAL CHARACTERISTICS OF CANCELLOUS BONE AT THE UPPER FEMORAL REGION

Mechanical behavior of trabecular bone at the upper femoral region of human bones has been studied by compression tests on trabecular bone specimens removed from normal femora obtained at autopsy. Compression tests were performed along three different axes of loading on wet specimens and high loading rates. Femoral head specimens proved to be the strongest for any axis of loading. Large variation in compressive strength and modulus of elasticity is seen within and between femoral bone samples. Anisotropy and differences in anisotropy for the different regions have been observed. A significant correlation between mechanical properties ( sigma max-E) and bone mineral content of the specimen was found. Tests on whole bone structures demonstrate that removal of the central part of the trabecular bone at the proximal femur reduces the strength for impact loading considerably ( plus or minus 50%).