Epidemiology of osteoarthritis

Osteoarthritis (OA) is the most common type of arthritis and the most common cause of disability in the elderly. It is a disease process that affects the total joint. OA may occur as the consequence of a number of different pathways that ultimately result in joint failure. It is increasingly recognized that inflammation is an important component in the pathophysiology of OA. The main clinical feature of OA is pain that tends to be transient early in the disease course but becomes persistent with disease progression. Radiographic features of OA may precede the development of pain. OA is the most common reason for joint replacement, and there have been striking increases in the rates of knee and hip replacement. Important OA risk factors include age, obesity, genetic factors and joint injury/trauma. With the aging of the population and the epidemic of obesity, there have been dramatic increases in the public health impact of OA, and the incidence, prevalence and public impact of OA are expected to rise.