Introduction: Ankylosing spondylitis (AS) is a chronic inflammatory disease, which can deteriorate the function of spine and peripheral joints. In addition to history and examination, imagin are important in diagnosing the disease. Especially, pelvic x-ray may shows pseudowidening, erosion and sclerosis sacroiliac joint. Spinal x-rays may also identify syndesmophytes. In more advanced stages, the spine may also be involved, forming a specific type of disease called “Bamboo spine”. The New York critera are used for diagnos of AS, which included radiologic and clinical criteria. The distribution of involvement in joints and bones in AS varies, but the classically is ascending involvement form sacroiliac joint, lumbar, and thoracic region.
Case presentation: Here is a case report of undiagnosed AS for 5 years, that despite the normal-appearing of the sacroiliac joint, has a severe involvement of the spinal column in the thoracic region, which called “Bamboo spine”. The time order of bone involvement in our patients is contrary to usual.
Also, according to New York criteria for AS, our case was not included the AS definition, however, she had clinical symptome of AS, the Bamboo spine, and a dramatic respons to treatment of AS.
Conclusion: Paying attention to the course of the AS, as well as attention to the clinic and various imaging of the different parts (heart, lumbar spine, and sacroiliac joint) will help physicians to diagnose AS, accurately and timely manner. Also, radiologic manifestation in rheumatologic disease may occur without any predictable order.