A lot of it depends on how severe the degree of kyphosis is, your age as the curve progressed, rotational component of the curve, ect. Very possible that you have scheuermann's disease or ideopathic scoliosis which contributed to. I think the degree of neuromuscular weakness which would be required to cause a thoracic kyphosis is pretty significant (think kids with cerebral palsy, people who are chronically in wheel chairs from spinal cord injuries).
I'm doubtful that going to a chiropractor or doing a bunch of exercises is going to help the shape of your back much (especially not the former). Exercises may help prevent future back pain, but that is likely the extent of it.