The difference between differentiated spondyloarthritis and ankylosing spondylitis mainly lies in the imaging performance, clinical symptoms, treatment difficulty, etc. It is recommended that patients go to the hospital for examination in time so as to clarify the specific causes of the disease. 1. Imaging performance: the performance of undifferentiated spondyloarthritis does not have typical features and does not meet the diagnostic criteria of arthritis, while ankylosing spondylitis has obvious imaging features and clear diagnostic criteria. 2. Clinical Symptoms: Undifferentiated spondylolisthesis only manifests itself as a slight limitation of the patient’s ability to rotate the spine, and therefore has a lesser impact on the patient. Ankylosing arthritis is characterized by ankylosis of the spine, inability to straighten the spine, and inability to raise the head, which has a greater impact on the patient. 3. Difficulty of treatment: Since the symptoms of end-differentiated spondyloarthritis are not serious, patients are able to relieve their symptoms with the use of anti-rheumatic drugs and proper rest, which makes it easier to treat. Ankylosing arthritis is generally serious, usually requires hospitalization, and in severe cases, surgery may be required. For specific cases, patients can consult a doctor at a local hospital to distinguish between undifferentiated spondyloarthritis and ankylosing arthritis.