If you develop the typical symptoms of ankylosing spondylitis described above, you should promptly visit a hospital with a rheumatology department. The diagnostic criteria mostly used internationally for the diagnosis of ankylosing spondylitis are the New York criteria developed in 1966, which mainly include: low back pain lasting at least 3 months, relieved by exercise; thoracic expiratory and inspiratory mobility difference of less than 2.5 cm measured at the level of the 4th rib space; restricted activity in three directions of lumbar flexion, retroversion and lateral bending; plus sacroiliac joint x-ray findings with one or both joint spaces blurring, narrowing or widening, jagged bone destruction, increased bone density, or loss of joint space, etc., then ankylosing spondylitis can be diagnosed. This criterion is strict and does not diagnose early ankylosing spondylitis. In order to obtain an early diagnosis of ankylosing spondylitis, a comprehensive clinical analysis should be performed in conjunction with the patient’s family history, the presence or absence of positive HLA-B27, the presence or absence of pain at the tendon end attachment site and CT examination of the sacroiliac joint. Patients with symptoms other than those typical of ankylosing spondylitis, but not enough to confirm the diagnosis of ankylosing spondylitis, may be diagnosed with “undifferentiated spondyloarthropathy” according to the European Spondyloarthropathy Study Group (ESSG) classification criteria or Amor criteria (details of which are not repeated). These patients should be monitored regularly and treated aggressively.