The diagnosis of spontaneous fracture needs to rely on a comprehensive analysis of clinical manifestations, bone mass measurement, radiographs and indicators of bone conversion biochemistry. Some patients with spontaneous fractures have no obvious symptoms, therefore, bone measurement is particularly important, and combined with biochemical tests, the diagnosis is generally not difficult. The metabolism of bone tissue is a cyclic process in which old bone is continuously resorbed and new bone is continuously formed, which is called bone rebuilding. The rate of bone rebuilding is called bone renewal rate or conversion rate. Measurement of blood and urine minerals and certain biochemical indexes can help determine the state of bone metabolism and the speed of bone renewal rate, which is important for the differential diagnosis of osteoporosis. Biochemical indexes of bone metabolism have the characteristics of rapid, sensitive and dynamic changes in bone metabolism observed in a short period of time, while BMD examination generally takes more than half a year to be in dynamic changes, therefore, biochemical examination is an essential index to observe the effect of drug treatment on bone metabolism in a short period of time, and can guide the timely revision of the treatment plan. 2.X-ray examination In the grassroots hospitals, due to the limitation of testing instruments, X-ray is still an easy and popular method to check osteoporosis. However, this method can only be qualitative, not quantitative, and is not sensitive enough. Generally, when the bone loss is more than 30%, the X-ray can be positive. It shows thinning of bone cortex, reduction or disappearance of bone trabeculae, widening of the gap of bone trabeculae, blurring of bone structure, double concave deformation of vertebral body or collapse of anterior edge in wedge shape, etc. 3.Bone mineral density measurement About 30%-50% of patients with degenerative osteoporosis do not have obvious symptoms such as bone pain, myalgia or low back pain, and the biochemical index changes are not significant, therefore, bone density test becomes an important objective basis for research and diagnosis.