Chronic lumbosacral joint strain is persistent and diffuse lumbar pain, with the lumbosacral region being the most severe, with no restriction of spinal movement and no special changes on X-ray. In acute lumbosacral joint strain, the pain is aggravated by activity and can be relieved after rest. Osteoarthritis often occurs in the elderly, characterized by degeneration and thickening of bones and cartilage, thickening of synovial membranes, and damage to joints such as the weight-bearing spine and knee joints are more common. Chronic low back pain is the main symptom of osteoarthritis involving the spine, which is easily confused with AS. In Forestier’s disease (age-related ankylosing bone hypertrophy), the spine is also affected by continuous bone hypertrophy, similar to AS, but the sacroiliac joints are normal and the intervertebral joints are not invaded. Tuberculous spondylitis Clinical symptoms such as spinal pain, pressure, stiffness, muscle atrophy, hunchback deformity, fever, and rapid blood sedimentation are similar to AS, but X-ray examination can be used to differentiate. In tuberculous spondylitis, the vertebral margins are blurred, the intervertebral space is narrowed, the anterior wedge is changed, there is no ligamentous calcification, sometimes there are shadows of paravertebral tuberculous pustules, and the sacroiliac joint is unilaterally involved. The rheumatoid arthritis is now recognized as not a specific type of RA, and there are many differences that distinguish the two; RA is more common in women, usually invades the small joints of the hands and feet first, and is bilaterally symmetrical; the sacroiliac joints are usually not involved, and if it invades the spine, it usually invades only the cervical spine, and there is no calcification of the paravertebral ligaments, there are rheumatoid subcutaneous nodules, and the serum is often positive for RF and negative for HLA-B27 antigen. Enteropathic arthropathy Ulcerative colitis, Crohn’s disease, or enterogenic lipid metabolism disorder (Whipple) can occur in spondylitis, and enteropathic arthropathy involves joints and radiographic changes similar to AS that are not easily distinguished, so it is necessary to look for intestinal signs and symptoms to differentiate. Ulcerative colitis has colonic mucosal ulceration, edema and bloody diarrhea. crohn’s disease has abdominal pain, nutritional disorders and fistula formation. whipple’s disease has steatorrhea and acute wasting. All of these contribute to the diagnosis of the primary disease. The rate of HLA-B27 positivity in enteropathic arthropathy is low. IgG is increased in the intestinal perfusion fluid of patients with Crohn’s disease, while IgG is basically normal in the intestinal perfusion fluid of patients with AS. spondylitis and sacroiliac arthritis can occur in both Reiter’s syndrome and psoriatic arthritis, but spondylitis generally occurs later and is milder, with less calcification of paravertebral tissues, and the ligamentous bones are predominantly non-marginal (calcification of fibrous tissue outside the fibrous ring) The formation of partial bone bridges between two adjacent vertebrae is different from the bamboo-like spine of AS. Sacroiliac arthritis is usually unilateral or bilateral asymmetric damage, while psoriatic arthritis can be differentiated by skin psoriasis damage. Tumors can also cause progressive pain, and a thorough examination is needed to clarify the diagnosis to avoid misdiagnosis. Acute rheumatic fever Some patients have initial clinical manifestations quite similar to acute rheumatic fever, or large joint swelling and pain, or accompanied by prolonged low-grade fever, weight loss, high fever and acute inflammation of peripheral joints as the first symptoms are not uncommon, such patients are mostly seen in adolescents, but also easy to be misdiagnosed for a long time. Individual patients with tuberculosis initially resemble tuberculosis and present with low-grade fever, night sweats, weakness, fatigue, weight loss, anemia, and sometimes unilateral hip inflammation, which can easily be misdiagnosed as tuberculosis. Relevant tuberculosis tests can be identified. Differentiation from seronegative spondyloarthropathies Reiter syndrome and psoriatic arthritis can occur with spondylitis and sacroiliitis, but spondylitis generally occurs later and is milder, with less calcification of paravertebral tissues and a non-marginal type of ligamentous osteophytes (calcification of fibrous tissue outside the fibrous ring), forming partial bony bridges between two adjacent vertebrae unlike the bamboo-like spine of ankylosing spondylitis. Sacroiliac arthritis is usually unilateral or bilateral asymmetrical, spondylolisthesis is rare, and there is no generalized osteoporosis. In addition, Reiter’s syndrome has conjunctivitis, uveitis, and mucosal skin damage, and psoriatic arthritis has skin psoriasis damage to differentiate. Enteropathic arthritis Ulcerative colitis, Crohn’s disease, and enterogenic lipid metabolism disorder (Whippe) can all occur in spondylitis, and enteropathic arthritis involves joints and radiographic changes similar to those of ankylosing spondylitis that are not easily distinguished, so it is necessary to look for intestinal signs and symptoms to differentiate them. Ulcerative colitis has colonic mucosal ulceration, edema and bloody diarrhea, Crohn’s disease has abdominal pain, nutritional disorders and impotence tube formation, and Whipple’s disease has steatorrhea and acute wasting. Enteropathic arthropathy has a low HLA-B27 positivity rate, and Crohn’s disease patients have increased IgG in intestinal perfusate, whereas IgG in intestinal perfusate is basically normal in patients with ankylosing spondylitis. Reactive arthritis often occurs secondary to infection elsewhere in the body, and foci of infection can usually be identified and antibiotics are effective. Treatment The goal of AS treatment is to control inflammation, reduce or alleviate symptoms, maintain normal posture and optimal functional position, and prevent deformity. The key to achieving these goals is early diagnosis and treatment with a combination of measures, including patient and family education, physical therapy, physiotherapy, medication, and surgical treatment. The treatment of the disease starts with education of patients and family members about the nature of the disease, its general course, possible measures and future prognosis, in order to enhance confidence and patience in fighting the disease and to obtain their understanding and close cooperation. Pay attention to maintaining normal posture and mobility in daily life, such as walking, sitting and standing with chest up and abdomen in, sleeping without pillows or with thin pillows, sleeping on hard wooden beds, taking supine or prone position, and lying prone for half an hour each morning and evening every day. Participate in labor and sports activities within your reach. Pay attention to posture at work to prevent spinal curvature deformity, etc. Maintain optimism, eliminate tension, anxiety, depression and fear; stop smoking and drinking; work and rest regularly and participate in medical physical exercise. Understand the role and side effects of drugs, learn to adjust the dose of drugs and deal with drug side effects, in order to cooperate with treatment and achieve better results. Physical therapy sports therapy is good for all kinds of chronic diseases, more important for AS. It can maintain the physiological curvature of the spine and prevent deformity. Maintain the mobility of the thorax and normal respiratory function. Maintain bone density and strength to prevent osteoporosis and limb wasting muscle atrophy, etc. Patients can adopt appropriate exercise modality and exercise amount according to their individual condition. If new pain persists for more than 2 hours without recovery, it indicates excessive exercise and the amount of exercise should be reduced or adjusted appropriately. Physiotherapy Physical therapy is generally available as heat therapy, such as hot bath, water tub bath or shower, mineral spring spa bath, etc., to increase local blood circulation, relax muscles, reduce pain, facilitate joint movement, maintain normal function and prevent deformity. Drug treatment NSAIDs: anti-inflammatory and pain relief, reduce stiffness and muscle spasm. Side effects are gastrointestinal reactions, kidney damage, and prolonged bleeding time. Pregnant and lactating women, more special attention should be paid. SSZ is an azo compound of 5-aminosalicylic acid (5-ASA) and sulfasalazine (SP), which has been used for the treatment of AS since the 1980’s. Side effects include gastrointestinal symptoms, skin rash, blood picture and liver function changes, but they are rare. It is advisable to check the blood picture and liver and kidney function regularly during the use of the drug. Methotrexate: The efficacy is reported to be similar to that of SSZ. The efficacy of oral and intravenous dosing is similar. Side effects include gastrointestinal reactions, bone marrow suppression, stomatitis, hair loss, etc. Check liver function and blood picture regularly during the drug use, and avoid drinking alcohol. Adrenocorticotropic hormone: In general, adrenocorticotropic hormone is not used to treat AS, but in acute iritis or peripheral arthritis when treatment with NSAIDs is ineffective, CS can be used for local injection or oral administration. Radix polyglycoside: The tincture of Radix et Rhizoma was initially used in China to treat AS, which has anti-inflammatory and analgesic effects and is more effective than tincture and easy to take. Side effects include gastrointestinal reactions, leukopenia, menstrual disorders and reduced sperm vitality, etc., which can be recovered after stopping the drug. Biological agents: tumor necrosis factor (TNF-α) antagonists and other (such as Yicep, adalimumab, etc.) is currently the best choice for the treatment of AS and other spinal joint diseases, those who have the conditions should try to choose. Surgical treatment Severe spinal hunchback and deformity can be corrected after the condition is stabilized, and lumbar spine deformity can be corrected by vertebral osteotomy. For cervical 7 thoracic 1 osteotomy can correct the serious deformity of cervical spine. Prognosis The disease is generally not life-threatening, but can be disabling and affect the patient’s normal life and work. Fortunately, severe spinal and joint deformities are only a minority of cases. Prevention Strong weight-bearing should be avoided, which can aggravate the lesion. Avoid maintaining one position for a long time without moving. If you have to sit for long periods of time, get up and move around for at least ten minutes every hour. Do not use low back restraints (which can reduce movement), which can worsen spondylitis. Avoid pillows and soft beds when sleeping. It is best to sleep flat on your back to keep it upright. When you wake up in the morning with a stiff back, you can take a hot bath to improve it. Hot compresses are also partially effective in relieving local pain. Do not smoke to avoid lung damage. Be careful to prevent trauma, always wear a seat belt when driving, and try not to ride a motorcycle. During the cold and wet seasons, it is important to prevent the recurrence of symptoms. Gastrointestinal and urinary tract infections often trigger spondylitis, so you should pay attention to dietary hygiene, drink more water, eat more vegetables and fruits, and avoid holding urine and constipation. Watch for symptoms of ankylosing spondylitis in other family members, such as lower back pain and morning stiffness. If so, seek medical attention as soon as possible.