In structural scoliosis, what happens when an individual flexes their spine?

In structural scoliosis, the spine is characterized by a fixed lateral curvature, which is compounded by rotation of the vertebrae. When an individual with structural scoliosis flexes their spine, the primary effects observed are an increase in the curvature and the rotation of the spine. This occurs because the curvature is not merely a flexible deformity that can be corrected through movements like flexion; rather, it is a fixed deformity that persists despite changes in position. As the individual flexes at the waist, the structural integrity of the spine leads to the curvature becoming more pronounced due to the underlying anatomical changes and the fixed relationships between the vertebrae and the ribs. Therefore, the correct answer highlights the inherent nature of structural scoliosis and how it responds to movements such as spinal flexion.