Seronegative spondyloarthropathy (SpA) is a general term for a group of diseases that are seronegative for rheumatoid factor and have spinal joint involvement. This group of diseases includes ankylosing spondylitis (AS), psoriatic arthritis (PsA), Reiter’s syndrome (RS), reactive arthritis (ReA), enteropathic arthritis, juvenile ankylosing spondylitis, juvenile spondyloarthropathy, and undifferentiated spondyloarthropathy (USPA). These diseases have the following clinical features in common: (1) familial aggregation; (2) close relationship with HLA-B27; (3) certain correlation with enteric gram-negative bacilli; (4) clinical manifestations may occur alone or overlapping: ocular, oral, intestinal, genital ulcers, urethritis, prostatitis and other skin mucosal changes; (5) peripheral arthritis is often the prominent manifestation of this disease (6) no rheumatoid nodules; (7) negative rheumatoid factor (RF); (8) sacroiliac arthritis, with the possibility of spinal involvement; (9) basic pathological changes are tendon telangiectasia or attachment point inflammation (common heel pain, foot pain). In the past, axial SpA was mostly detected late in the course of the disease, i.e., it had already progressed to AS, and characteristic changes of the vertebrae were visible on X-ray plain films. 2009 October 16-21, the 73rd Annual American College of Rheumatology (ACR/ARPH) was held in Philadelphia, and the participating experts announced the new classification criteria for SpA: when imaging findings are available: imaging suggestive of sacroiliac arthritis + ≥1 SpA clinical features; without imaging findings: HLA-B27 + ≥ 2 other SpA clinical features. Clinical features: 1, IBP – at least 4 of 5 should be present (1) onset before age 40; (2) insidious onset; (3) improvement with exercise; (4) failure to improve with rest; (5) nocturnal pain (improves upon waking) 2.Arthritis – synovitis that has been or is currently recommended to be diagnosed by a physician. 3.Tendonitis (heel) – there was or is spontaneous pain or pressure pain at the insertion site of the Achilles tendon or plantar fascia. 4.Uveitis —- – Previous or currently existing anterior uveitis diagnosed by an ophthalmologist. 5. Finger (toe) inflammation —- Previously or currently present with physician-confirmed finger (toe) inflammation. 6. Psoriasis —- ever or currently present with a physician’s diagnosis of psoriasis. 7, Crohn’s disease/ulcerative colitis —- ever or currently existing Crohn’s disease/ulcerative colitis. 8, Good response to treatment with NSAIDs —- Pain disappears or improves significantly 24-48 hours after treatment with adequate doses of NSAIDs. 9, Family history of SpA —- refers to one generation of relatives (parents, brothers, sisters, children) or two generations of relatives (grandparents, grandparents, uncles, aunts, uncles and nephews) with any of the following diseases: (1) AS; (2) psoriasis; (3) acute uveitis; (4) reactive arthritis; (5) inflammatory bowel disease. 10, HLA-B27 positive. 11, CRP increased —- exceeds the upper limit of normal, the patient has back pain and other causes of increased CRP have been excluded. The most significant change in the new criteria compared to the previous criteria is the inclusion of magnetic resonance imaging (MRI), which helps physicians confirm the diagnosis early and initiate treatment in a timely manner. This is because early treatment, either with non-steroidal anti-inflammatory drugs (NSAIDs) or tumor necrosis factor (TNF) inhibitors, will help patients slow the progression of spondyloarthritis (SpA). With the proven efficacy of tumor necrosis factor (TNF) alpha antagonists for early lesions, the use of new criteria facilitates patients to receive early treatment before structural damage occurs. This will have a profound impact on the treatment and further research of medial SpA.