Imaging examination; 1, CT examination; “discogenic low back pain” patients, the disc of the three layers of the annulus fibrosus appeared rupture, but the morphology of the change is not big, like a tire lead hairline fracture, but the shape has not changed, so the CT examination to see the disc is normal or mild bulging. 2, MR examination; in normal, the human body’s intervertebral disc contains 70% -80% of the water, discogenic low back pain patient’s intervertebral disc in the degeneration of the basis of the degeneration of the disc pathophysiological manifestations of diversified, but the main manifestation of dehydration, MR examination can be clearly seen in the dehydrated intervertebral disc in the T2-weighted phase of the manifestation of the low signal, known as the “black disc”, whereas the normal disc is normal or mildly bulging. “Normal intervertebral discs contain water and show high signals, also known as “white discs”. Although a “black disc” can be seen on MR, it does not mean that the annulus fibrosus of the disc is ruptured. CT examination is only bulging, MR examination is only “black disc”, CT and MR examination can not clearly diagnose discogenic low back pain. 3, discography: discography can clarify whether the annulus fibrosus of the intervertebral disc is ruptured or not. The tissue structure of the intervertebral disc is like an egg, the yolk is like the nucleus pulposus, and the protein is like the annulus fibrosus. Under the fluoroscopic view of CT and C-arm machine, the puncture needle enters into the nucleus pulposus, and injects the contrast agent, if you feel the pressure is big when injecting, and the measurement of the contrast agent is only 0.5 ml, and the contrast agent gathers inside the yolk (inside the nucleus pulposus), then the annulus fibrosus of the disc is complete and has not been ruptured. It means that the fibrous annulus of the disc is intact and has not ruptured. If the contrast dose is >0.5 ml and the contrast reaches the annulus fibrosus, the annulus fibrosus of the disc is ruptured. The larger the contrast dose, the more pronounced the rupture of the annulus fibrosus of the intervertebral disc. When the intervertebral disc’s annulus fibrosus ruptures, the contrast agent can also bring chemicals from the nucleus pulposus through the ruptured annulus fibrosus into the spinal canal, and most patients can experience pain, which is also one of the criteria for diagnosing discogenic low back pain. Therefore, discography can be clearly diagnosed with discogenic low back pain if there is little hand pressure during injection, the contrast agent enters the annulus fibrosus, the contrast agent measures >0.5 ml, and the patient experiences pain. However, the technical content of discography is relatively high. Usually, discography is performed under X-ray fluoroscopic guidance or CT guidance, and due to the limitations of the respective machines, the diagnostic accuracy is 60%-75%, and false positives and false negatives may occur in 35%-40%. By placing the mobile “C” fluoroscope under the CT machine, we have increased the accuracy of discography to 98%. Currently, discography is recognized by the medical community as the gold standard for the diagnosis of “discogenic” low back pain.