TEXT B When former President Ronald Reagan fell and broke his hip two weeks ago, he joined a group of more than 350,000 elderly Americans who fracture their hips each year. At 89 and suffering from advanced Alzheimer's disease, Reagan is in one of the highest-risk groups for this type of accident. The incidence of hip fractures not only increases after age 50 but doubles every five to six years as the risk of falling increases. Slipping and tumbling are not the only causes of hip fractures weakened bones sometimes break spontaneously. But falling is the major cause, representing 90% of all hip fractures. These... ... 17. The following are all specific measures to guard against injuries with the EXCEPTION of