Abstract:We investigated hip joint destruction in patients with rheumatoid arthritis before and after the availability of methotrexate and biological disease-modifying anti-rheumatic drugs DMARDs in Japan. A total of 35 patients with 45 diseased joints underwent total hip arthroplasty from 1995 to 1999 Group A: 21 hips in 15 patients and from 2006 to 2010 Group B: 24 hips in 20 patients . We monitored the oral administration of therapeutic drugs and prednisolone, measured preoperative C-reactive protein CRP levels, estimated the Larsen grade and bone defects of the acetabulum oor using simple X-ray images, and calculated the bone defect rate of the femoral head. The intake of preoperative oral prednisolone was signi cantly less in Group B than in Group A P 0.05 , as were preoperative CRP levels P 0.05 .