The Natural History of Scheuermann's Kyphosis.

Adolescent idiopathic kyphosis, also known as Scheuermann's kyphosis (SK), is a prominent form of thoracic or thoracolumbar spine hyperkyphosis affecting up to 8% of adolescents. This condition is characterized by structural vertebral changes and a kyphotic Cobb angle greater than 45°. This review examines the long-term progression and outcomes of SK when untreated, integrating findings from multiple decades of research, including landmark studies. By engaging with this review, we hope to convey a consolidated understanding of how Scheuermann's kyphosis behaves across the lifespan when untreated; from the modest rate of post-maturity progression to the clinical signals that separate stable curves from those likely to cause functional difficulty. The information can provide clarity when advising families, planning follow-up, and determining when continued non-operative care is reasonable or when surgical intervention might be considered. Key Concepts: (1)Scheuermann's kyphosis affects roughly eight percent of adolescents and is defined by structural vertebral wedging that produces a thoracic Cobb angle greater than 45°.(2)Longitudinal cohorts show that after skeletal maturity, the curve enlarges only about a third to half a degree each year, with very few patients ever exceeding 100°.(3)Pain and everyday function are usually acceptable, yet individuals whose curves pass 75° and develop forward sagittal imbalance report noticeably greater disability.(4)Radiographic size alone does not predict symptoms; the combination of deformity and loss of global alignment is a more reliable signal for clinical vigilance.(5)Conservative measures such as physiotherapy and bracing during growth suffice for most patients, while operative consultation is reserved for those with progressive imbalance or persistent discomfort.