Here is a link to a good article on psoriatic arthritis (PsA) at the Cleveland Clinic:
https://my.clevelandclinic.org/health/diseases/13286-psoriatic-arthritis#prevention
Have you made any diet changes? I have had psoriasis on my scalp for decades and I have been fighting PsA for a couple years. I have been avoiding red meats, dairy and tomatoes. That helped, but I found that free radicals cause inflammation at the joints and you need high amounts of anthocyanins to knock them out. Anthocyanins are what makes blueberries blue, black beans black and red cabbage red. Having a "black and blue and red" diet makes a big difference. The sharp pain in my joints are decreasing to very minimal amount. (I am not on any prescriptions.)