I went on Anastrozole in October of 2020. By November of 2021 my knee pain was crippling. Literally. In December I made two changes at the same time so I can't be sure which worked. I switched to Letrozole, and I started taking collagen supplements. The improvement happened quickly. I'm 68 so I do have mild arthritis, but to date I mostly experience occasional stiffness if immobile too long. Otherwise I feel my knees are back to where they were pre-Cancer treatment. As you are on a hiatus, adding collagen would provide a clear answer.