Three years ago (Nov '16) I had burst fractured my T 5-7 vertebrae and ended up with about 7" of titanium rods for my fusion. When I started riding again in the summer of 2017 I really needed a more 'upright' position , mostly because it was painful to keep my head up, looking forward. For riding I used a hybrid with flat handle bars ....this was all fine, even though the surgery site with all the cut and damaged nerves hurt like hell.
Just recently I switched to a gravel bike (Trek Checkpoint) and can say that I think it has actually helped my recovery. My first couple rides hurt, but several months later I am feeling better about switching bikes.....the Checkpoint forces my head up so I can see, which makes my neck stronger. The more aggressive riding position has helped because it stretches out my back and, I assume, works on the scar tissue. It's been a long painful 3 yers, but I'm healing. Best wishes to you and recovery!