Epidemiology of Knee Osteoarthritis

Osteoarthritis (OA) is the most common form of aging of the joints. The knee joint is the key structure in the lower extremity and has much influence on activities of daily life (ADL) and the quality of life (QOL) in elderly persons. These include standing, walking, running, jumping, stair climbing, deep knee bending, such as squatting or sitting Japanese style, and other lower extremity tasks. Approximately 10 to 15% of people aged 60 years and older have symptomatic knee OA^<1)>. Therefore, knee OA is a major source of chronic disability and is becoming a serious public health problem. In order to clarify the pathomechanics of this disease and to determine suitable preventive strategies, detailed knowledge of the prevalence, progression, and the risk factors associated with knee OA is essential. This review focuses on the epidemiology and impact of knee OA