OARSI/OMERACT Criteria of Being Considered a Candidate for Total Joint Replacement in Knee/Hip Osteoarthritis as an Endpoint in Clinical Trials Evaluating Potential Disease Modifying Osteoarthritic Drugs

Objective. A disease-modifying osteoarthritic drug (DMOAD) should interfere with the cartilage breakdown observed and improve symptoms or prevent deterioration of the patient's clinical condition. We propose a composite index including structural and symptomatic variables of osteoarthritis (OA) as criteria for being considered a candidate for total joint replacement as an endpoint in clinical trials evaluating potential DMOAD. Methods. An OARSI/OMERACT task force conducted this study in 3 steps: (1) The 3 main domains - pain, function, structure - were revisited; (2) For each of the domains a non-acceptable state and a relevant progression for their structure were defined; and (3) a set of criteria was proposed combining the information from these 3 domains. Results. A questionnaire was elaborated for the domains pain and function. Systematic research of the literature and evaluation of different databases concluded that the domain structure should be evaluated by radiological joint space width in millimeters. An unacceptable radiographic progression was defined as a change in the joint space width over the measurement error. An international, cross-sectional study is proposing a definition of a nonacceptable symptom state. Conclusion. The objective of the ongoing OARSI/OMERACT initiative is to propose criteria for being considered a candidate for total joint replacement to be used as an endpoint in clinical trials evaluating potential DMOAD. The preliminary steps of this initiative have been completed. (J Rheumatol 2009;36:2097-9; doi:10.3899/jrheum.090365)