This study will quantify the impact of low-dose fluoride treatment on the fracture susceptibility of the femur and spine of menopausal women with osteopenia. From a clinical trial, a subset of women taking a range of fluoride doses or a placebo for 12 months will have virtual 3D reconstructions of bone biopsies from micro CT. Bone metabolism markers and spatial density will be measured. The micro-bone model will be loaded until failure, providing a micro fracture score. The micro-bone will be scaled to the whole bone using multiscale methods. Physiological loads from walking and stair-climbing combined with shock impact from falling down and hip blows will provide a real-world fracture score. Fracture scores will be related to fluoride dose levels, bone density, bone growth and histology. Reduced fracture susceptibility will provide evidence for low-dose fluoride as an economical, non-patented and painless method of treatment for osteoporosis.