Mild dextroscoliosis of thoracic spine.not sure of the degree.have asymmetry in legs.have upper back pain somtimes wen doing something continuously

If mild don't worry : Mild scoliosis does not need any specific treatment as does any leg length difference under 3/4 of an inch. In terms of the upper back pain occasionally , try some core strengthening exercises or taking short breaks to avoid a a continuous load or stress on your back.

Scoliosis: You may have this. I would see a pm;r spine specialist to further evaluate your options for treatment. With asymmetry in legs, you may need a shoe insert/orthotic to address the leg length discrepancy.