The difference between lumbar sprain and bone metastasis is mainly reflected in the mechanism of occurrence, site of pain, and nature of pain. 1. Mechanism of occurrence: lumbar sprains often have obvious causes of injury, such as poor posture, acute trauma, and bone metastases, which have a past history of cancer. 2. Pain site: the pain site of lumbar sprain is generally more limited, while the pain caused by bone metastasis is localized bone destruction, which can lead to persistent pain in the surrounding tissues. 3. The nature of pain: the pain of lumbar sprain is generally tolerable and can usually be controlled by rest or anti-inflammatory analgesic drugs, while the pain of bone metastasis is mostly persistent sharp pain, usually unbearable, and painkillers are difficult to relieve. In addition to the above differences, there are many other differences between the two, such as the duration of pain, pain accompanied by symptoms, etc. When pain in the lower back, it is recommended to consult a doctor in a timely manner, to clarify the cause of the disease, and promptly rule out bone metastasis and other serious diseases.