0: Bilateral primary osteoarthritis of knee.

What is primary arthritis?

Primary osteoarthritis is caused by the breakdown of cartilage, a rubbery material that eases the friction in your joints. It can happen in any joint but usually affects your fingers, thumbs, spine, hips, knees, or big toes.

What is degenerative changes in knee?

Degenerative joint disease of the knee is also known as osteoarthritis (OA). OA occurs when the cartilage that cushions your knee joint gradually deteriorates.