Evaluating the contribution of bone micro-architecture, density and bone strength to fracture at clinically relevant sites using a novel instrument:An Xtreme CT study

Osteoporosis is a chronic condition whereby bones become fragile and individuals are predisposed to fracture. Osteoporosis may occur in all older people but it most frequently affects post-menopausal women. Worldwide, more than nine million osteoporosis-related fractures occur annually. Older Canadians sustain more than 24,000 hip fractures annually — which levies a substantial physical, emotional and economic burden on individuals and the health care system. By 2040, this number is expected to increase to 90,000 at a cost of $2.4 billion. The likelihood of a person sustaining a fracture is related to their bone strength and their propensity to fall. Bone strength is related to bone’s material and structural properties. Currently, DXA (dual-energy x-ray absorptiometry) is the most commonly used diagnostic tool to measure bone health. However this technology has limitations in that it provides a two-dimensional (2-D) representation of bone, a 3-D structure. Further, DXA does not capture the nuances of bone geometry and structure that underpin bone strength. Recently, a high resolution imaging system (the Xtreme CT scanner) was developed that is able to assess bone mass, geometry and bone microarchitecture. The extent to which this novel technology is able to predict bone failure is currently unknown. Thus, Sarah Braid will utilize state-of-the-art imaging techniques (X-treme CT and pQCT) to evaluate bone strength and its components – and most importantly – link these evaluative tools with the susceptibility of a bone to fracture. The results of her research will enhance our ability to assess fracture risk so as to prevent fractures in vulnerable populations in future.