ObjectiveTo assess the clinical outcome of chemical synovectomy with rifampicin in hemophilic arthropathy by using the World Federation of Hemophilia (WFH) scoring system and plain radiograph.MethodsWe performed rifampicin synovectomy (RS) on 30 joints of 28 hemophilic patients diagnosed as hemophilic arthropathy stage I–III (based on Fernandez-Palazzi clinical classification). Clinical status (bleeding frequency, pain, joint physical status) and radiological staging were evaluated as parts of the WFH scoring system before and 1 year after RS. The patients were divided into two groups by the Arnold-Hilgartner scale of the initial X-ray as stage 3 or less for the low-stage group (n=17) and over 3 for the high-stage group (n=13).ResultsTotal WFH joint physical scores were reduced after injection, and the number of bleeding episodes and pain showed especially significant improvement. For other subscores of the WFH joint physical score, only swelling, range of motion, and crepitus showed statistically significant improvement. According to the severity of the radiologic finding, the WFH joint physical score of both the low-stage and high-stage groups showed significant improvement. In the radiological aspect, the low-stage group, without joint space narrowing at the initial plain radiograph, showed no further aggravation after injection. However, in the high-stage group, radiology found aggravation regardless of the procedure.ConclusionIt is suggested that chemical synovectomy with rifampicin may prevent hemarthrosis and improve clinical symptoms. Especially in the early stage of arthropathy without joint-space narrowing, it seems to have an additional benefit that delays radiological aggravation and preserves joint status.