Like many medical terms osteoporosis is derived from the Greek. The strict translation is porous bones, from osteo, meaning bone, and porosis meaning very porous. Osteoporosis is a degenerative disease, which leads to thousands of broken bones every year and huge expenditure for the NHS, running at over £1 billion a year. Osteoporosis is a condition that is characterised by a loss of bone mass ? density ? coupled with changes in the bone architecture. As a result the bones are weakened and liable to fracture so that an incident which would otherwise have been a simple fall can all too easily become a disaster.

A fall in older age is very often the spark which starts off a series of events, finally culminating in the patient's death. Each year, 60,000 people fracture their hip as the result of a fall. Orthopaedic surgeons pin and plate the fracture, and are proud of their patient's initial progress and how well the bone has knitted together. However few mention, and many probably don't even realise, that within six months, one in five of those elderly people who apparently had done so well at the time of the operation after sustaining a hip fracture will have died as a result of the osteoporosis. As well as the 60,000 who fracture their femurs, 40,000 crush one of the spinal bones and 50,000 break their wrists. Other bones are less often broken as the result of osteoporosis but it is not uncommon for it to be a factor in the fracture of the bones of the foot, the collar bone and ribs.

Just as there is a discreet, polite silence about the death rate, which follows even apparently successful repairs of the hip, so do people rarely talk about osteoporosis in men. Older men, as well as women, have crumbly bones. As life expectancy increases it is not only Father Christmas who is hunched and pot bellied. Any septuagenarian who has attended a university reunion will be surprised to find the once towering second row forwards who had once played for Scotland, or even South Africa, now several inches shorter and pushing in, scrum half sized, from the outside of the ruck around the bar.

One in 12 men will develop osteoporosis at some point of their lives, a smaller proportion than in women ? one in three women do, but it is not an insignificant number. More women die as the result of an osteoporotic fracture than they do from cancers of the cervix, ovaries and uterus put together. Equally surprisingly, more men die from osteoporotic fractures than do women from cancer of the hip. Likewise, there are more hip fractures in men than there are diagnosed cases of cancer of the prostate.

The factors which lead to osteoporosis are genetic and environmental. Heavily boned people, male or female, are less likely to develop it than those who are slender and finely boned. In women anorexia, faddy non dairy diets and inadequate vitamin D, smoking, excessive drinking and taking either too much or too little exercise are risk factors for osteoporosis.

The hormonal links with osteoporosis have been obvious and accepted for many years. Not by chance do those women who are still menstruating have some protection from osteoporosis, the high oestrogen levels of pre menopausal life ensure this. If their periods end early so do they develop osteoporosis at a younger age. Oestrogens are not the only hormones to be a factor, in both sexes changes inthyroid hormone levels or parathyroid hormone production are significant risk factors and taking oral steroids are an important predisposing cause of osteoporosis at any age group. Whatever the medical reason, which has necessitated the taking of steroid hormones, osteoporosis may be an adverse effect of the treatment. In both men and women, the risk of osteoporosis is greatly increased and always needs treatments if long term oral cortico steroids have been prescribed.

The obvious treatment for women to prevent their increased risk was to prescribe HRT so that the beneficial effects of oestrogen might be enjoyed for longer. Even before the recent alarm over the possible link between HRT and breast cancer was established it was already becoming apparent that HRT as a means of preventing osteoporosis was unlikely to be useful after the age of 57 and 58. Several years ago in many centres it had been decided that the maximum advantage was achieved by prescribing HRT over the perimenopausal years. Treatment was started rather earlier than had hitherto been the case, and had certainly been completed by the mid to late fifties. As it became increasingly obvious that HRT wasn't as successful as it had previously been supposed the reasons for its use were beginning to revert to what they had been when the HRT hormones were first introduced. That is to say they should be given to alleviate severe symptoms of the menopause, to treat an artificially early menopause, but not necessarily as the drug of choice to prevent osteoporosis. Except in cases of early menopause they should certainly not be prescribed as a means of reducing the incidence of heart disease and possibly strokes and Alzheimer's. The benefits of their use for these latter cardiovascular conditions is not borne-out by well conducted trials.

Other drugs have become even more important in the treatment of osteoporosis as a result of the withdrawal of HRT for this purpose. The most obvious group are the bone regulators, the bisphonates, alendronate, etidronate and risedronate. The best known of these is Fosamax alendronate. The easiest form in which to take Fosamax is as a once weekly. It is manufactured by Merck, Sharp and Dome and acts in quite a different way from HRT. It works by inhibiting the body's cellular system which is designed to reabsorb older bones. Bones are constantly being laid down under the influence of cells known as osteoblasts and older bone is removed by osteoclasts. Fosamax slows down the action of osteoclasts so that the old bone lasts longer and the overall strength of the bone is greater. Fosamax can also be taken only a daily basis when it is a hundred times more potent than Didronel etidronate. Many, if not most women, should take bisphosphonates at the time of the menopause. Men may take them with advantage but start at a later age group.

Forsteo, teriparatide, has been developed by Eli Lilly as another form of treatment for advanced osteoporosis. It mimics human parathyroid hormone and stimulates osteoblastic activity ? the activity of the osteoblasts, the bone building cells. Whereas Fosamax slows down osteoclasts so that existing bone is preserved for a longer time, Forsteo increases the mass of new bone and hence its strength.

Other hormones, but not actually oestrogens ? such drugs as Livial ? which have an anti-osteoporotic function and are also useful against menopausal symptoms. These haven't been discredited but there is now a natural reluctance and caution about prescribing any hormonal preparation. Evista raloxifene is a selective oestrogen receptor modulator, it is not recommended if there is any question of breath problems. Most doctors now consider Fosamax, either taken once daily or once weekly as the drug of choice for osteoporosis.

Whatever the drugs that are used to prevent or treat osteoporosis, it is essential that the patient should also be taking an adequate supply of calcium and vitamin D. Most doctors also recommend a multi vitamin and mineral supplement.