What characterizes Scheuermann's disease in terms of spinal alignment?

Scheuermann's disease is primarily characterized by a marked fixed thoracic kyphosis. This condition typically develops during adolescence and involves the wedging of vertebrae in the thoracic spine, leading to an exaggerated kyphotic deformity. In response to this thoracic kyphosis, patients often exhibit compensatory lumbar lordosis. The body naturally tries to maintain an upright posture, and the lumbar region compensates for the thoracic curvature to help stabilize the overall spinal alignment.

This combination of pronounced thoracic kyphosis and compensatory lumbar lordosis is a hallmark of Scheuermann's disease, demonstrating the body's adaptive mechanisms to structural changes in the spine caused by the disease. While the other options describe various conditions related to spinal alignment, they do not accurately reflect the specific characteristics associated with Scheuermann's disease.