I’m assuming your dermatologist has prescribed many creams.
If you work with your hands those two digits are especially susceptible
to friction and wear and tear. The Koebner reaction causing flares explains this. When I used steroid at night I preferred white cotton gloves over
the steroid topical. Baby your hand with gloves at rough work with irritating
activities during the day. Frequent steroid use can cause thinning and
fragility limiting their use. Have you tried oral or topical apremilast.
Tacrolimus and calcipotriene creams are are other options. They are $$.
Do you have nail changes or arthritis? I became aware of psoriasis being an
internal system disease when I developed psoriatic arthritis in spite of
minimal skin area involved. Dermatologists may overlook it is a cardiac
risk factor in itself. Have your doctor screen you for that as well as doing
testing for inflammation.