Henry, it is an old fashioned idea that Osteo Arthritis is due to wear / hard work. Early use of the appropriate drugs will help to slow the progress. Also as CR says, diet can help. There is an interesting article
here:
I have an inflamatory arthritis (not rheumatoid, but something similar) and once it was diagnosed, the drugs have meant that I have suffered no further joint deterioration in the past 10 years as well as pretty much removing the symptoms.
Best to see a Rheumatologist, not a GP who inevitably has little in-depth knowledge.
HC