From experience, how difficult is it to get insurance to cover the cost of the surgery?

I’m 5’8, 125-130, small frame and a 34DD. I have loose shoulder joints, arthritis in the shoulders, upper back/neck pain and skin irritation just to name a few of my issues. I go to the chiro weekly for adjustments, always focused on upper back/shoulders. Ive been to PT and seen an orthopedic for shoulder problems. My Gyn is also aware of my complaints and problems. I just want to sure I am fully prepared. Do insurance companies have a breast to body ratio?