Hi @redlo your experience resonates with me. I was in a similar situation when my DXA scan came back after 13mo on Forteo. The results showed good improvements in spine and TBS score; my bone markers indicated a great response to Forteo too. However, my hip bmd had a whopping 7.6% drop in just 13mo! The conflicting results did not make any sense! My DXA results ended up being re-examined. Technical errors were found and it turned out the hip bmd did not change during first 13mo on Forteo. When I finished Forteo treatment, my hips (r/l) had 5.7%/3.6% bmd increase, both "significant with 95% confidence". TBS score improved as well to a level thats within normal range.

Sometimes 6mo treatment of Forteo may not be long enough to give meanful bmd changes. You could look for LSC (least significant change) - usually in DXA report's footnote if you have them. In my report, the LSC is expressed in (numerical number) g/cm^2 for bmd. So instead of comparing T scores, we could compare the differences in bmd (before and after). If the difference is greater than the LSC, then the % change in bmd is signicant hence your Tscore too. Otherwise, there is nothing to worry about even with your slight decrease in T score which could be just variations in scan readings.

All the best to you!