Diagnosed at 29 with osteoarthritis from ortho doc. mri and xr confirmed.knees have no cartilagand hands and wrists are bad. no sports, injuries.why?

Nobody Knows: Although osteoarthritis is commonly thought of as "wear and tear, " we are learning more and more that this is also a problem of cartilage biology. We don't understand why some people develop oa without any obvious "wear" events and others seem to tolerate a lifetime of high-intensity activity.

Not sure: At this age, it is unlikely to be simple osteoarthritis. I would consult with a rheumatologist.