A longitudinal study of growth velocity and development of secondary gender characteristics versus onset of idiopathic scoliosis.

This study focused on evaluating the impact of the adolescent growth spurt on the onset of idiopathic scoliosis. A total of 698 students (362 girls and 336 boys aged nine to 12 years) were followed for three years to study their growth in the pubertal period and changes in spinal status. Every six months measurements were taken of body height and the development of secondary gender characteristics was recorded. The onset of the adolescent growth spurt could thus be detected in each child. When children with and without scoliosis were compared, it became evident that scoliotic children grew faster. Girls whose scoliosis developed from a previously normal body posture showed a peak height velocity (PHV) of 8.1 cm per year, whereas girls with a normal body posture throughout the pubertal stage had a PHV of 7.1 cm per year. The most rapid growth spurt was observed in Stages 2 and 3 of breast and pubic hair development. Simultaneously, the most frequent spinal status changes occurred in Stages 2 and 3 of sexual maturity; they were twice as frequent as in Stage 1 and four times as frequent as in Stages 4 and 5. Students in whom scoliosis developed in puberty during the adolescent growth spurt grew faster than their peers who did not develop scoliosis, which need not imply that they will eventually be taller after growth is completed.