How is osteoarthritis diagnosed?

So the diagnosis of knee osteoarthritis is based on clinical examination, usually assessment in clinic or when we take a history of other symptoms to find out if you have knee pain and then we examine for findings or signs of osteoarthritis such as swelling, tenderness or discomfort along the joint, creptus or noises in the joint, stiffness, limitation in the range of motion and then if there severe cases of deformity and other signs as well as signs of instability in the knee. Then we normally request x-rays usually weight-bearing x-rays so x-rays I call them in the dynamic fashion so the knee being exposed to the weight to be able to diagnose if there is evidence of osteoarthritis which where we look at certain factors such as narrowing of the joint space, formation of new bone, which are the osteophytes, thickening of the bone, or what we call subchondral sclerosis, and also any evidence of loose fragments or loose bodies, etc. If the arthritis is not evidenced, sometimes we request further imaging such as an MRI scan, which is a magnetic resonance imaging, which is a more detailed scan of the joint. It tells us to detect early osteoarthritis, however that's not indicated at all in severe osteoarthritis. So if the x-ray shows evidence of osteoarthritis and it's fairly obvious the MRI scan might will not change the management as such. And then we sometimes do blood tests when we think of inflammatory arthritis such as rheumatoid gout etc and that can be helpful if you suspect inflammatory and throbothy as well.