joint pain from Tamoxifen

I am struggling with severe joint pain since I have started taking Tamoxifen. I am baffled by the fact that despite me finding various women with the same problem, joint pain is not a recognised side effect of Tamoxifen and my oncologist claims I am the only patient she knows who is complaining about this. Been to see a rheumatologist, who has excluded this being either due to rheumatism or arthritis.

I have changed the medication from tablets to liquid Tamoxifen, because during my research I found a hint indicating that the problem has occurred since Tamoxifen was changed from patented to generic form, but so far I have not had much positive results form the change.

Diclofenac dulls the pain a little, but my walking range is still down to an hour, after that I am hopping lame as the pain is particularly affecting my feet..

Does anyone have advice what might help ?

Looking forward to hear form you.

Urte