Sudden lumbar pain may be caused by lumbar fracture due to osteoporosis, lumbar disc herniation or acute lumbar sprain, or lumbar pain caused by kidney stone cannot be excluded. Therefore, it is recommended to improve the relevant auxiliary examinations to confirm the diagnosis, including front and side x-ray of the lumbar spine, MRI of the lumbar spine, ultrasound of the kidney and CT of the lumbar intervertebral disc, etc. After the diagnosis is confirmed, the corresponding treatment will be given, and the acute stage can be treated symptomatically with oral non-steroidal anti-inflammatory drugs for pain. If the fracture of the lumbar spine is caused by osteoporosis, surgery may be required if necessary; if it is caused by acute lumbar sprain, conservative treatment can achieve satisfactory results; if it is caused by lumbar disc herniation, conservative treatment, physiotherapy and lumbar traction can achieve satisfactory results; if it is caused by kidney stone, extracorporeal lithotripsy may be required under the guidance of a urologist. If it is caused by kidney stones, it may be necessary to take extracorporeal lithotripsy and other means to relieve the symptoms under the guidance of urologists.