Abstract
Idiopathic scoliosis is a growing spine disorder. Only a perfect knowledge of normal growth parameters such as bone age, stages of puberty, standing and sitting height, arm spam, Tanner stages, and weight allow the surgeon to plan the best treatment at the right moment. Measurements should be repeated and carefully recorded at regular intervals. Puberty is not a sudden event: it has a gradual onset and it is preceded by an incubation phase. It is not a point on a chart: it is a period that lasts two years beginning at a bone age of 11 and 13 years in girls and in boys, respectively. Two years of rapid growth ("acceleration phase") are followed by three years of steady reduction of growth rates ("deceleration phase"). Skeletal maturation needs to be evaluated carefully to evaluate the progression risk of scoliosis during the phase of accelerating growth velocity. This article explains how to identify pubertal growth spurt, both clinically and radiographically, in order to correctly monitor patients with idiopathic scoliosis.