Pelvic anteroposterior digital radiography in understanding hip joint involvement of ankylosing spondylitis

OUYANG Su-shan; WANG Gao-ya; LI Min; LIU Xu-dong; DENG Han-wen; ZHU Zi-wei; XU Feng; YANG Ping-ting; XIAO Wei-guo

doi:10.19538/j.nk2017060114

Abstract：Objective To explore the clinical features of pelvic anteroposterior digital radiography of ankylosing spondylitis (AS) and its significance in the evaluation of hip joint involvement in AS patients.Method Seventy-nine outpatients or hospitalized AS patients diagnosed in the Department of Rheumatology and Immunology,the first Affiliated Hospital of China Medical University,from January 1st,2010 to December 3 l th,2015,undertook pelvic anteroposterior digital radiography.We made detailed analysis of hip joint involvement and compared the difference in the clinical characteristics between normal and abnormal groups.The data and results were statistically analyzed.Results In this study,there were 48 (60.8％) patients whose radiograph of the pelvis showed abnormalities in the hip joint,among which enthesitis-related chronic changes and joint space narrowing were the most typical characteristics.Compared with patients with normal hip joints (normal group),the disease course was longer[(9.1±6.2)years vs(5.5±6.3)years,P=0.02],and the levels of serum C-reactive protein (CRP) increased in patients of abnormal group[(34.8±34.4)mg/L vs (19.1±16.5)mg/L,P=0.02].The proportion of patients with hip pain was also significantly higher than that of patients in abnormal group(40/48vs 13/31,P＜0.01).In addition,there were 64 patients with typical sacroiliac joint changes,including limited or diffused sacral and iliac sclerosis,erosion,with or without joint space changes.These abnormalities all should be taken seriously and given a timely assessment.Conclusion Radiography of the pelvis,the most basic means of imaging methods,can reflect the characteristics of hip joint diseases in patients with AS,and it is of great significance in helping clinicians understand hip joint diseases and optimize clinical management.We recommend that it should be taken as a clinical routine examination to screen the hip joint diseases.