Like reducing rib cage width or narrowing the shoulders?
I spoke to a senior surgeon, told me these procedures are not commonly performed, but there are well accepted procedures for similar conditions. Thoracic /orthopedic surgeons may perform these surgeries in safe methods such as:
http://healthpages.org/surgical-care/shoulder-arthroscopy/
This is very interesting, perhaps others can elaborate on such procedures and of relative safety/risks and of their availability.
Trans socialite Amanda Lapore did this. The procedure was extreme though, involved cracking lower ribs and bracing, she said it took a long time to heal, I'm sure it was worth it though. She has an hour glass figure. Sad part is to actually find a doctor willing to do it. Sounds painful :o