Osteoporosis: false-colour scanning electron micrograph (SEM) of the appearance of spongy (cancellous) bone in osteoporosis (brittle bone disease). Osteoporosis describes a reduction in bone density, resulting in increased brittleness and a greater risk of fractures, especially those of the vertebrae & femoral head. This is reflected here in the thin appearance of the trabeculae (the bony network) in the spongy bone that forms the core of the long bones. The high incidence of osteoporosis in elderly women is attributed to a post-menopausal decline in hormone production. Magnification: x100 at 6x7cm size.