The result is pain, deformity, and loss of joint motion. Under normal circumstances, the joints' extremely slippery cartilage covering permits the joint surfaces to glide against each other. However, as damage to the protective cartilage covering proceeds, the sensitive bone ends are exposed and begin to wear out. Since cartilage has no blood supply, the major source of healing that other tissues of the body use for repair is eliminated. Thus, the joint becomes painful as the damaged joint surfaces progresses inexorably towards total destruction.
Age of onset varies depending on the involved joint.
OA of the hip or knee is particularly disabling because it limits ambulation, but the disease also strikes the hands, the spine and the feet with the same destructive joint process. The disease can also result from trauma. Total joint replacements of the knee and hip have been very successful in restoring near normal, pain free, mobility of the joints. However, despite the success of joint replacement surgery, we still have not been able to cure osteoarthritis or prevent the disease from progressing to the point where surgery is necessary. An exciting new area of interest among scientists and physicians is the possibility of restoring osteoarthritic joints.