Bone metastases are the most common malignant tumors of bone. Under comprehensive treatment, many cancer patients can get better therapeutic effect and prolong the survival period. According to statistics, bone metastasis occurs in about 1/4 of patients with malignant tumors, so bone metastases should always be considered in the differential diagnosis, especially more common in elderly patients. 1000 patients who died of cancer were found to have bone metastases in 27% of the deceased through autopsy. About 70% of malignant bone tumors are metastases, and their incidence varies with the type and course of the primary tumor. The longest occurring sites of metastatic tumors are the spine, pelvis, ribs and proximal limbs; metastases to the distal parts of the knee and elbow are uncommon, and about 50% of the metastases to the distal limbs are lung metastases. Breast, prostate, lung, and kidney cancers account for 80% of bone metastases. In men, almost 60% of bone metastases are prostate cancer and 25% are lung cancer. In women, about 70% of bone metastases are breast cancer, and another 30% are mainly thyroid, uterine, and kidney cancers. Some other primary tumors that produce bone metastases are stomach, colon, bladder, melanoma, and neurogenic tumors. A common route of metastasis is the movement of tumor emboli, most of which are carried to the central circulatory system via the lymphatic system and thoracic ducts before being transported to the periphery by the arterial system. Breast, prostate, lung, and kidney cancers account for 80% of bone metastases Others: stomach, colon, bladder, melanoma, neurogenic tumors.