What areas were x rayed? C spine ? T spine?
With your whole ribs sx, I would think a full spine or at both those mentioned, since you mention possible scoliosis too.
there is also rotational scoliosis...where the spine will twist as well as curve to the sides.
I would assume

that if anything suspicious shows up on x rays, then MRI or CT should be the follow up.
From what you have been describing neuro seems to be mainly more of your sx than vascular type. but I may have forgotten all the sx listed.
You might re list all your sx in this thread, maybe the worst first and then down to least.
might help us suggest the best testing ideas for you.
I hope some that know will answer this one.
[which test would better show inflammation and/or scar tissue, an mri or an ultrasound?]
I would like to know if any of the tests will show scar tissue, because I don't recall if it has been mentioned before.
Only thing I recall reading here is during the surgery the Dr finds it and cleans it out.