Background: Studies have shown that 27% to 38% of girls with
adolescent idiopathic scoliosis have systemic osteopenia. The aim of this
study was to investigate whether osteopenia could serve as one of the
important prognostic factors in predicting curve progression.
Methods: A prospective study was performed in 324 adolescent girls
with adolescent idiopathic scoliosis who had a mean age of thirteen and a half
years. Bone mineral density of the spine and both hips was measured at the
time of the clinical diagnosis of scoliosis. All patients were followed
longitudinally until skeletal maturity or until the curve had progressed
=6°. The univariate chi-square test and stepwise logistic regression
were used to predict the prevalence of curve progression, and a receiver
operating characteristic curve was plotted.
Results: The overall prevalence of curve progression was 50%. The
prevalence of osteopenia at the spine and hips was 27.5% and 23.1%,
respectively. A larger initial Cobb angle (odds ratio = 4.6), a lower Risser
grade (odds ratio = 4.7), premenarchal status (odds ratio = 2.5), osteopenia
in the femoral neck of the hip on the side of the concavity (odds ratio =
2.3), and a younger age at the time of diagnosis (odds ratio = 2.1) were
identified as risk factors in predicting curve progression. A predictive model
was established, and the area under the receiver operating characteristic
curve of the model was 0.80 (p < 0.01).
Conclusion: Osteopenia may be an important risk factor in curve
progression. The measurement of bone mineral density at the time of diagnosis
may serve as an additional objective measurement in predicting curve
progression in adolescent idiopathic scoliosis. The bone mineral
density-inclusive predictive model may be used in treatment planning for
patients with adolescent idiopathic scoliosis who are at high risk of curve
Level of Evidence: Prognostic Level I. See Instructions
to Authors for a complete description of levels of evidence.