Knee osteoarthritis is the most common joint disorder causing knee arthritis. The incidence of knee osteoarthritis increases with age, and with an incidence of 240 out of every 100,000 person-years, which is more than twice the incidence of either hand osteoarthritis or hip osteoarthritis. Knee osteoarthritis is often comorbid with obesity, another common chronic disease; obesity can increase the risk and severity of knee osteoarthritis due to increased joint loading, less physical activity, and loss of protective muscle strength. The risk of having osteoarthritis is increased by minor trauma at a younger age, such as sports-related meniscal tear and ligamentous injuries, which can account for up to 40-50% of all knee osteoarthritis. Other diseases that can result in knee arthritis, and may require total knee arthroplasty (TKA), include inflammatory arthritis, such as spondyloarthritis, rheumatoid arthritis, and psoriatic arthritis. Knee arthritis involves degeneration of the knee, resulting in loss of articular cartilage, capsular stretching, ligament laxity, formation of osteophytes, subchondral cysts and sclerosis, weakness of the associated muscles, and pain.
Last date updated on March, 2021