Differences in erect sitting and natural sitting spinal alignment-insights into a new paradigm and implications in deformity correction.

Background Context: Sitting spinal alignment is increasingly recognized as a factor influencing strategy for deformity correction. Considering that most individuals sit for longer hours in a "slumped" rather than in an erect posture, greater understanding of the natural sitting posture is warranted.

Purpose: This study aimed to investigate the differences in sagittal spinal alignment between two common sitting postures: a natural, patient-preferred posture; and an erect, investigator-controlled posture that is commonly used in alignment studies.