@rjtx I would think that you would be starting at your primary care physician and depending on that evaluation, they may refer her to another doctor or for an X-ray. You may also want to ask for a physical therapy evaluation because there can be tightness in chest or neck muscles that can contribute to problems with tightness in ribs or even twisting ribs. I have thoracic outlet syndrome (TOS) which does this and my physical therapist had to loosen that up. A lot of doctors are not familiar with TOS, but if that is suspected, a neurologist may be able to diagnose it. If it is just a muscular problem, physical therapy may be able to help.
https://www.mayoclinic.org/diseases-conditions/thoracic-outlet-syndrome/symptoms-causes/syc-20353988
Do you have a list of questions to ask at the appointment?