Pro Bono plastic surger

Would a dr be likely to do a pro bono surgery for a person with a disability, I was diagnosed with severe degenerative disk disease and my doctor told me, that my weight does not help. (I am 5'5 and weight 155.) I have been on phentermine for about a year and have lost 30lbs, I have not lost anymore weight, because of the back pain i can not exercise as it is too pain-full.  I have been getting steroid injections for the back pain, although not enough for me to exercise. I have an 18 month old son that it is hard for me to take care of because of this dx. If a dr would do pro bono is there any facilities in the Chicago, IL area that would do this for a discounted rate? Please help.