Microcrack distributions in bone : effects of stress and bone mineral density

Abstract

The work is divided into four main sections. Chapter 2 it was performed compression and bending tests, with the use of a dye sequence technique. The tests were carried out to detect and measure microdamage development after reaching the fracture, taking into account different stresses within cross sections of whole bones. The ovine whole bones were scanned with the use of DXA technique for Bone Mineral Density levels information (BMD), for which comparisons between the bones microdamage developments and their mechanical endurance towards applied stresses, with the addition of the distribution of cracks regarding BMD levels could be performed. Compression tests in bovine bone specimens gave microcracks developed in bones cycled towards the fracture with the application of considerably high fatigue stresses; bending tests in whole ovine radiae gave microcracks developed under differing stresses and BMD levels, the stresses taken within the bones cross sections.