Low back pain may not be ankylosing spondylitis, ankylosing spondylitis low back pain characterized by inflammatory low back pain, different in nature from other causes of low back pain, in addition, ankylosing spondylitis low back pain is relatively rare compared to other causes of low back pain, clinical misdiagnosis of ankylosing spondylitis may also occur.1. Low back pain due to ankylosing spondylitis: ankylosing spondylitis is important to see whether the sacroiliac joint is inflammation, and how to determine whether it has inflammation, mainly through imaging, that is, X-ray, CT or magnetic resonance imaging (MRI). The clinical manifestations are usually significant joint swelling and pain and tendon attachment point swelling, with imaging of the sacroiliac joint and spine clearly showing the presence of inflammation and elevated inflammatory markers C-reactive protein or blood sedimentation. In addition, ankylosing spondylitis is usually slow onset, with symptoms lasting at least three months, accompanied by morning stiffness, back discomfort can be reduced or disappear after activity; 2, other causes of low back pain: such as degenerative lesions of the sacroiliac joints, lumbar disc herniation, etc., may also lead to low back pain, but the nature of low back pain caused by ankylosing spondylitis is different, degenerative lesions of the sacroiliac joints are usually caused by aging and strain, and may have slight blurring and sclerosis, etc. on imaging, and generally no inflammatory changes. Lumbar disc herniation, on the other hand, is also associated with strain, aging, etc., and may show signs of compression of nerves or surrounding tissues, mostly without inflammatory manifestations. Therefore, whether a patient with low back pain is indeed suffering from ankylosing spondylitis-like disease, it is important to emphasize the essence of the presence of “inflammation”, that is, in the absence of clear evidence of “inflammation” as described above, low back pain may not really be ankylosing spondylitis, and if the patient has If there is some degree of anxiety or depression, the patient may be more appropriately seen by a medical psychologist or psychosomatic physician.