NEW YORK (Wall Street Journal) ¿ Hip and spine fractures are among the most common disabling injuries of the elderly. But because they are more common in women, strategies to prevent them are rarely directed at men.

"We've figured out what to do with women, but men have been largely ignored," says Angela Shepherd of the University of Texas Medical Branch in Galveston. That's starting to change as more men live longer and find their lives changed for the worse after breaking a bone.

Dr. Shepherd recently published a system doctors can use to identify men at risk of osteoporosis, a weakening of the bones that raises the risk of fractures. She was drawn to the field after an 89-year-old patient fell and broke his hip while dancing with his wife on New Year's Eve. "I don't think he ever danced again after that," Dr. Shepherd says. "He had to use a walker."

One in four men over 50 will have an osteoporosis-related fracture during his lifetime (for women the figure is one in two), according to the National Institutes of Health. The National Osteoporosis Foundation plans to release guidelines for bone health in men next year, according to Ethel Siris, president of the foundation and director of an osteoporosis centre at Columbia University Medical Center.

Even without the guidelines, there are certain clear risk factors for men to be aware of, as well as steps they can take throughout life to keep bones healthy.

Unlike women, whose risk of osteoporosis increases dramatically after menopause, men's risk increases slowly and typically doesn't become significant until later in life.

Dr. Shepherd's system, published in the Annals of Family Medicine, uses three variables: age, weight (lighter men are at higher risk) and a history of chronic obstructive pulmonary disease, which mainly affects smokers.

Smoking and excessive drinking both increase the risk of osteoporosis.

Certain drugs can raise the risk dramatically. Hormone-blocking drugs used to treat prostate cancer, such as Lupron, can leave men with weaker bones, as can long-term steroid treatment for diseases such as rheumatoid arthritis and asthma.

Men who believe they may be at high risk can ask their doctor if they should undergo a bone mineral density test to diagnose osteoporosis. In severe cases, prescription osteoporosis drugs may be appropriate. But there are things all men can do to lower their risk of developing osteoporosis and breaking bones in old age.

Getting enough calcium and vitamin D helps. And exercise during childhood and adolescence, while the skeleton is still growing, builds bone.

That's important because it helps raise the so-called peak bone mass reached during young adulthood, before the long-term decline in bone mass begins.

"The less you start with, the less you're going to end up with when you're really at the age when osteoporosis risk is very important," says Eric Orwoll of Oregon Health & Science University, who is conducting a long-term study of osteoporosis in men.

Staying fit into old age is also important; it means stronger muscles and better coordination and balance, all of which help avoid falls, a key trigger for fractures in the elderly.

There is some evidence that the type of exercise ¿ weight-bearing, versus non-weight-bearing ¿ can make a difference for bones. For example, some research suggests competitive cyclists, who spend hours a week on their bicycles but little time running or jumping, may tend to have weaker bones than runners. Josh Johnson, who is 31 and describes himself as an "elite-level amateur" cyclist, recently participated in one such study, and learned that he's at risk for developing osteoporosis later in life. "It definitely opened my eyes," he says. "I bought a jump rope and I used it for a little while, but I honestly haven't stayed real faithful to it."

Some experts nevertheless say that the more important point is simply to exercise. "I have not been convinced that the tiny increase in bone density (from weight-bearing exercise) is really that critical," Dr. Siris says. "If my patients say, 'I don't enjoy weight-bearing exercise, should I swim?' I say, 'Yes."'