Physical activity and knee osteoarthritis

Knee osteoarthritis is a major cause of pain and disability in older people, and accounts for some 9000 knee arthroplasties carried out annually in England and Wales.

Although there are many pathophysiological mechanisms that may culminate in “joint failure”, the main determinants of knee osteoarthritis are thought to be constitutional predisposition to the disorder at several joint sites, combined with local biomechanical stress. Established risk factors include older age, female sex, evidence of osteoarthritis at other joint sites, obesity, and previous injury or surgery to the knee. Evidence is accumulating that certain physical activities at work and during leisure also increase the risk of knee osteoarthritis.