Welcome to Gaia! :: View User's Journal | Gaia Journals

2. Osteoarthritis and the knee
Osteoarthritis is a very common condition amongst older adults, but precise estimates are difficult to obtain due to differences in diagnostic criteria [6]. In the knee, evidence of ha tag is apparent on radiographs in up to 50% of the population over the age of 75, whilst up to one third have symptomatic knee OA [1]. Use of more sensitive tests such as MRI demonstrates evidence of osteoarthritis in up to 89% of people over the age of 50, irrespective of the presence of symptoms [7]. Whilst most people with osteoarthritis remain asymptomatic, end-stage osteoarthritis requiring knee replacement is increasingly common. In the USA, the incidence of TKR has increased from 402,100 in 2005 to 676,000 in 2009, and is projected to increase to 3.5 million per year by 2030 [8] and [9].
The principal symptom of osteoarthritis is pain, with varying degrees of stiffness and (usually varus) deformity. Whilst osteoarthritis is a progressive disease, the level of pain associated with it often fluctuates and can be affected by factors such as weight, activity level, climate and time of day. The level of pain experienced by patients with osteoarthritis correlates with radiological measures of disease severity, but this is inconsistent: a proportion of patients with end-stage disease on knee radiographs will remain asymptomatic and never present to a doctor [10].