Mid upper back pain since may. had ct of chest showed arthritis in thoracic and mild scoliosis. ct was clear. what could b causing the pain?

Mid upper back: Consider muscle spasm and nerve root irritation as possible causes. Strains, sprains are common. Tumors and infectious processes are less common there.

Hard to say: It is good to know that you had a ct scan of the chest, which can rule out many potential causes. An MRI is the test of choice for evaluating the spine and can show things such as a thoracic disc herniation, for example, that would not typically show up on a ct scan of the chest. Thank you for the question.