The diagnosis of ankylosing spondylitis is a major challenge, and most patients are difficult to diagnose early, most notably because of the lack of early diagnostic criteria and highly specific laboratory indices at this stage. We have found in clinical practice that the diagnostic accuracy of the New York criteria, as revised by VanderLinden in 1984, is indeed very high, but many early patients simply cannot be included within the requirements of the criteria, indicating that the criteria are set too high or the conditions are too rigid, giving little room for clinical maneuvering. If we consider this issue from a pathological point of view or from the common sense of the development of everything in the world, the pathological changes of AS must have a process, and the radiological changes are never accumulated in one day, regardless of sclerosis or erosion. In addition, the radiological indicators only emphasize the sacroiliac joint and do not mention the pathological changes in other areas. In fact, there are two major categories of pathological indicators of AS, one is arthritis and the other is tendon telangiectasia. The longest occurrence of spinal arthritis is in the sacroiliac joint, followed by the small intervertebral joints, and the most common in peripheral arthritis are hip, knee and ankle. With the popularity of spiral CT examinations in clinical applications, pathological changes with this unknown lesion or unappreciated pathology will be detected. In our clinical practice, we found that the small intervertebral joints of lumbar 5 sacral 1 and lumbar 4 and 5 and the attachment of the ligamentum flavum at the lower edge of the inner lumbar plate of lumbar 4.5 could be seen as a resident area of gross, sclerotic or small erosions similar to sacroiliac arthritis, and combined with the clinical manifestations, we thought it might be related to AS, while comparing with the lower edge of the inner vertebral plate of CT disc herniation alone, we found that the surface of the latter was smooth, and from the lower edge of the inner vertebral plate resected intraoperatively, at the ligamentum flavum attachment its surface is smoother and does not show obvious convexity or concavity. This indicates that the changes such as roughness and erosion shown by CT examination were caused by inflammatory lesions. In our group, three patients with lumbar disc herniation were found to have significant erosion of the bone at the attachment of the ligamentum flavum at the lower edge of the vertebral plate, in addition to disc herniation, after the CT scan of the lumbar spine, and further examination confirmed that they had AS. synovitis and musculoskeletal ligamentitis. The advantage of systemic administration is the simplicity and wide distribution of the drug, but the disadvantage is the low local concentration of the drug, which makes it difficult to achieve effective control of inflammation in the short term. Targeted interventional therapy is a local precise drug delivery, it can not only inject the drug into the joint cavity, but also inject the drug directly into the tendons, fascia, ligaments and other tissues where the blood supply is not abundant, and the local drug concentration is very insufficient in these tissues due to poor blood supply during systemic drug delivery, so the method of local injection can effectively compensate for the local efficacy of systemic drug delivery.