Intraarticular Opioids Vs Glucocorticosteroids in Gonarthritis

Inclusion Criteria: * Arthritis according to the American Rheumatism Association or osteoarthritis of the knee * age older than 18 years * active gonarthritis in the setting of a rheumatic inflammatory disease such as rheumatoid arthritis, spondyloarthropathies, undifferentiated oligoarthritis or monarthritis since at least 4 weeks with proof of joint or ostearthritis of the knee effusion in ultrasound * visual analogue scale (pain) \>30 mm * weight between 50 and 90 kg * signed informed consent * negative urine pregnancy test in women of child-bearing potential Exclusion Criteria: * pregnancy / lactation * severe infection, suspicion for opportunistic infection within the last 2 months (herpes zoster, cytomegaly-, pneumocystis carinii-infection), HIV- infection * malignant disease * severe cardiac, renal, hematologic, pulmonary, neurologic, gastrointestinal (amongst others gastric or duodenal ulcer) or hepatic (viral hepatitis, toxic liver disease etc) disease, uncontrolled high blood pressure, recurrent thrombosis/ embolism * psychiatric disease * significant bone marrow dysfunction with impaired hematopoiesis * one of the following laboratory findings: thrombocytopenia \< 100 /nl, Quick \< 50% * significant pathological findings in physical examination, especially findings indicating an infectious cause for arthritis (septic arthritis) or Lyme arthritis * participation in clinical trials within the last 30 days * intake of illegal drugs (such as cocaine, heroin...), sub…