Prevalence of osteoporosis At present, the total number of people suffering from osteoporosis around the world is over 200 million, and in the case of the United States, women over 45 years old suffer from osteoporosis as many as 15-20 million people every year, resulting in 1.3-1.5 million cases of fractures. At present, there are about 84 million osteoporosis patients in China, accounting for 6.6% of the total population. The annual incidence of fracture due to osteoporosis is about 9.6%, and the trend is increasing year by year. According to the World Health Organization, the incidence of osteoporosis has now jumped to the seventh place among the common diseases and diseases in the world. Since the 1980s, foreign medical circles have started a wave of research on osteoporosis, and it has become a rapidly developing field. Nowadays, the prevention and treatment of osteoporosis to prevent fracture has been put on the same level of importance as the treatment of hypertension to prevent stroke, treatment of hyperlipidemia and prevention of myocardial infarction in the world. Definition of osteoporosis From the point of view of diagnosis, the diagnosis of osteoporosis is not only limited to the diagnosis of bone quantity, but also focuses more on the changes in bone quality and the development and research of methods for the evaluation of bone quality. Osteoporosis has not only changes in bone mass, but also morphological changes in bone, which ultimately lead to a decrease in the mechanical properties of bone. Classification of osteoporosis Osteoporosis is divided into three major categories. The first category is primary osteoporosis, which is further divided into two types, namely type I (postmenopausal osteoporosis) and type II (senile osteoporosis). The second category is secondary osteoporosis, such as hyperthyroidism osteoporosis and diabetic osteoporosis. The third category is idiopathic osteoporosis of unknown cause, commonly found in adolescents or adults aged 8-14 years, such as hereditary osteoporosis. According to the scope of osteoporosis, it can be divided into the following two categories: (1) systemic osteoporosis: such as senile osteoporosis, hyperthyroidism osteoporosis, etc. (2) Limited osteoporosis: such as rheumatoid arthritis osteoporosis, local osteoporosis caused by limb plaster fixation, etc.