Hello & welcome,
Sorry to hear your symptoms (sx) are getting worse , even with Alexander technique & chiropractic. Are both of those addressing overall & upper body alignment/postures?
That is one of the things that can cause sx increases, the head/shoulders forward of body mid line.
Or you could also have some other accumulating factors happening.
Work, hobbies, sports = old injuries from any of these? (scar tissue/adhesions)
Did you have any kinds of sx in your younger years? What is your age now? Sometimes @ middle age these things start to show up more.
Most likely the extra c ribs have always been there so I'm wondering if they affected you at all back then , and what may have brought out the sx recently.
Has anything changed recently before or since the sx started?
Extra c ribs can be large, small or only partially formed, so good imaging should show how that factors in.
I would guess that larger/full set would cause more problems and surgery would be needed for those cases, but small or partial, maybe not.
It all depends on the person and how it is affecting them with pain levels, other sx and overall quality of life...
In general the extra c rib removal surgery (with a qualified surgeon of course) is usually well tolerated and recovery is good.
Have you seen the self help photos on my photo page? Might be worth trying to see if they help at all.