When back pain occurs, plain film or CT have their own advantages and can be chosen according to the suspected disease. 1. Plain film: The examination is relatively cheap and simple, and has good diagnostic value for certain diseases causing low back pain, such as urological diseases such as urolithiasis, which can be seen in most cases, and rheumatic diseases such as ankylosing spondylitis, which can be seen in the sacroiliac joints, which can be seen in the bamboo-like changes. 2.CT: The examination utilizes radiation, tomography scanning of the human body, the results of its tomographic images of lesions with higher resolution than the flat film. It has the significance of guiding the treatment of certain diseases causing lumbar pain, such as clarifying the degree of herniation of lumbar disc herniation, the site to assist in the choice of surgery. If you have clinical symptoms such as low back pain, it is recommended to go to a regular hospital and choose the appropriate auxiliary examination according to the needs of your condition under the guidance of your doctor.