Osteoarthritis is a deterioration of cartilage and overgrowth of bone often due to "wear and tear". Rheumatoid arthritis is the inflammation of a joint's connective tissues, such as the synovial membranes, which leads to the destruction of the articular cartilage.
Review Date: 10/31/2010 Reviewed By: C. Benjamin Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Dept of Orthopaedic Surgery. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.