Osteoarthritis is the most common form of arthritis and is associated with the aging process. Osteoarthritis is a chronic disease causing the deterioration of the cartilage within a joint.
For most people, the cause of osteoarthritis is unknown, but metabolic, genetic, chemical, and mechanical factors play a role in its development. Symptoms of osteoarthritis include loss of flexibility, limited movement, and pain and swelling within the joint. The condition results from injury to the cartilage, which normally absorbs stress and covers the bones, so they can move smoothly.
The cartilage of the affected joint is roughened and becomes worn down. As the disease progresses, the cartilage becomes completely worn down and the bone rubs on bone. Bony spurs usually develop around the margins of the joint.
Part of the pain results from these bone spurs, which can restrict the joint’s movement as well.
Update Date 8/3/2013
Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.