美国估计有1500—2000万人患骨质疏松,45岁以上由此而造成髋部骨折也在20万人以上。因髋部骨折入院的病人15%在短期内去世,30%也在一年内死于并发症。估计30～50%的幸存者也不可能恢复到骨折以前的功能水平。Rigg 和 Melton 将骨质疏松分为两种类型。第Ⅰ The United States estimates that 15 million to 20 million people suffer from osteoporosis. Over the age of 45, more than 200,000 people have hip fractures. 15% of hospitalized patients with hip fractures have died in the short term and 30% have died of complications within a year. It is estimated that 30 to 50% of survivors will not be able to recover to the level of pre-fracture function. Rigg and Melton classify osteoporosis into two types. I