What is psoriatic arthritis

[Fred]

How do they tell if it is PsA and not other types of arthritis? What if you have osteoarthritis and PsA? Can they tell the difference?

I would say a good dermatologist / rheumatologist would be able to spot the difference.

Psoriatic arthritis causes swelling around the joints and can go red, my toes went like big radishes they call it "dactylitis" Also they can tell by looking at the nails, they will show signs of psoriatic arthritis. And with psoriatic arthritis it comes and goes, and can be in one joint today and a different one tomorrow.

Osteoarthritis on the other hand gradually gets worse and rarely goes down. It also doesn't show in the nails, or cause dactylitis.

Having said that I'm no expert and that is only my thoughts.