Cancer spreading to bones will have persistent severe pain, which should reach at least 5 points according to the pain score, and a few patients will reach 8 points or above, which is usually difficult for patients to endure, and they can’t even have normal rest and activities. Cancer spreading to bones usually indicates that the tumor has developed to an advanced stage. Malignant tumors that are prone to bone metastasis mainly include breast cancer, prostate cancer, lung cancer, kidney cancer, etc., which will cause serious destruction of bone, and therefore stimulate the periosteal nerves to make the pain very intense, and usually require the use of strong analgesic drugs to relieve clinical symptoms, such as oral morphine, oxycodone, fentanyl topical and morphine injection. When pain is stabilized by short-acting drug control, maintenance therapy should be switched to long-acting extended-release dosage forms.