Thoracic spine degeneration in adult spinal deformity patients: impact on baseline alignment, reciprocal changes, and proximal junctional kyphosis. - Diebo BG; Singh M; Nassar JE; Hostin R; Gupta MC; Klineberg EO; Mundis GM Jr; Okonkwo DO; Hamilton KD; Passias PG; Protopsaltis TS; Kim HJ; et al. (European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society, 2026)