If your scoliosis surgery was in your thoracic spine, there are nerves that affect gastrointestinal system (stomach, liver, gallbladder, esophagus, etc.). It is possible the stomach issues and pain may be worsened if the nerves were injured during the surgery. See attached picture of spine and nerves. Good luck with your neurologist. Spinal injections can help with inflammation and nerve pain in your spine (I have had 3-4 of them and scheduled for another in December). They have helped me reduce nerve pain and improve mobility.