Hi @Lorraine S
I was on Letrozole for 3 years before developing trigger thumbs and finger. My oncologist gave me a month break before swapping me to Tamoxifen (I was on Tamoxifen for 2 years before Letrozole). I found acupuncture seemed to help the pain.
I have no hand pain or stiffness on Tamoxifen 3 months later. The right thumb still triggers sometimes but I have full strength in it now. I could not even sign my name before I stopped Letrozole. I had other issues which made Tamoxifen the best choice for me.