Progression Risk of Idiopathic Juvenile Scoliosis During Pubertal Growth

Study Design. A retrospective study investigated the progression risk of juvenile scoliosis until skeletal maturity or spinal fusion. Objectives. To define risk factors of curve progression during pubertal growth and analyze the timing of arthrodesis. Summary of Background Data. Juvenile scoliosis is characterized by a major, extremely variable progression risk. Peak growth velocity is the most critical period. Curve progression related to growth needs to be analyzed critically for an adequate treatment. Methods. A total of 205 patients, including 163 girls and 42 boys, with juvenile scoliosis were reviewed at skeletal maturity. The scoliosis was divided into juvenile I with an onset of 4–7 years (52 patients) and juvenile II with an onset of 8–10 years (153). Standing and sitting height, weight, Tanner signs, skeletal age, and menarche were regularly assessed. Topographies and Cobb angles of primary and secondary curves were referred to the pubertal growth diagram. Results. Of 205 patients, 99 (48.3%) were operated on. Of 109 curves ≤20° at onset of puberty, 15.6% progressed >45° and were fused. Of 56 curves of 21° to 30°, the surgical rate increased to 75.0%. It was 100% for curves >30°. Curves >20°, which increased and were operated on, progressed significantly during peak growth velocity (P = 0.0014). Curves that progressed by 6° to 10°/y were fused in 70.9%, curves which increased >10°/y in 100% of cases (P = 0.0001). This risk was highest for primary thoracic curves: King V, III, and II (P = 0.0001). There was no difference between males and females or juvenile I and II. Conclusions. Curve pattern, Cobb angle at onset of puberty, and curve progression velocity are strong predictive factors of curve progression. Juvenile scoliosis >30° increases rapidly and presents a 100% prognosis for surgery (curve >40° to 45°). Anticipation is necessary if the scoliosis progresses during the first year of puberty. The prediction is difficult for curves of 21° to 30° during the first 2 years of puberty. Curve pattern and curve progression velocity are useful to detect which curves are likely to progress. From this retrospective analysis, spinal fusion could have been indicated earlier sometimes. An earlier intervention is probably preferable to obtain better curve reduction on a supple spine, even if a perivertebral fusion is necessary. We use the 3 parameters for operative indications. If an early spinal fusion leads to better curve correction needs to be verified on prospective data.