Pain in the thoracic spine that has not improved after four months should be looked into. The potential structures that can cause pain are the disc, facet, rib-vertebra junction and the nerve root. There are other structures that are not spine related and although very rare, should be differentially considered such as the heart and aorta.
Whatever the injured structure is, it is unlikely that this will lead to adjacent structure failure. A good workup by a spine surgeon or knowledgeable PM&R doctor will be helpful. You might need an MRI.
Dr. Corenman