I can breath through my stomach and breath deep no pain but when i expand my chest it hurts a little i have ankylosis spondylitis ?

A.S. often causes: inflammation of the rib cartilages. When your chest expands as you take a deep breath, the nerves that run along the ribs can send out pain signals to your brain. "Ouch!" You should talk to your doctor about this. The inability to take deep breaths & to cough when needed can interfere with normal lung function, making you winded and prone to chest infections. Best wishes. Dr. Anne

Still lung breathing: Maybe you had voice training as a youth and so you don't use move your chest wall as much when you breathe. As to your ankylosing spondylitis you might want to seek out care at Mayo Clinic or HSS in NY. Norman Cousins wrote a great book on his dealing with his AS called "Anatomy of An Illness". He was the former editor of The Atlantic. Good luck!