Ankylosing spondylitis (AS) is a disease in which inflammation of the sacroiliac joints and spinal attachment points is the main symptom. There is a strong association with HLA-B27. Certain microorganisms (e.g. Klebsiella) have common antigens with the susceptible person’s own tissue and can trigger an abnormal immune response. It is a chronic inflammatory disease characterized by fibrosis and ossification of the large joints of the extremities, as well as the intervertebral disc rings and adjacent connective tissue, and joint ankylosis. Why is ankylosing spondylitis difficult to treat? 1, ankylosing spondylitis in the treatment of the present its originally attributed to orthopedic diseases, from the surface of the disease bone and joint lesions caused by patients with joint ankylosis, the actual ankylosing spondylitis there is an authentic immune system diseases, cumulative multiple organs at the same time. Surgery can solve the problem of joint bridge ankylosis, but it does not solve the problem of continued postoperative bridge formation, and surgical treatment often ends in failure. Immunological treatment is difficult to solve the problem of inflammation at the end of the tendon, and it is difficult to stop the formation of bone bridges. 2. The pathogenesis of ankylosing spondylitis is very complex, it has a clear family genetic tendency, he also has a clear racial genetic tendency, but causes the onset of the disease is closely related to the autoimmune function at a certain stage of low, and also related to the body local infection, but also involves environmental factors. Ankylosing spondylitis is a multi-organ, multi-system disease that involves genetics, immunology, internal medicine, and orthopedics, making it a multidisciplinary disease. 3, ankylosing spondylitis regardless of the treatment method, the effect is relatively slow, and thus the patient can not adhere to the treatment, thus losing confidence in the treatment, and eventually stop treatment. At the same time, patients do not carry out effective joint function exercise due to fear of pain, resulting in joint ankylosis soon, and patients do not want to continue to adhere to treatment.