Caption

Osteoporosis. False-colour scanning electron micrograph of the trabeculae in the cancellous (spongy) bone tissue affected by osteoporosis. The cancellous tissue fills the interior of the bones and in osteoporosis its density decreases, increasing the brittleness of the bones and the probability of fractures. In this case, a spinal vertebra is affected and many small round dark areas on the bone are empty. Osteoporosis usually affects women, above all after the menopause, because their ovaries no longer produce oestrogen hormones which help to maintain bone mass. Magnification: x43 when printed at 10 centimetres across.