Persistent osteopenia in adolescent idiopathic scoliosis: A longitudinal follow-up study

Study Design. A follow-up study assessing the bone mineral dynamics in adolescent patients with idiopathic scoliosis and associated osteopenia. Objectives. To investigate whether osteopenia in patients with adolescent idiopathic scoliosis is a transient phenomenon or a persistent problem. Summary of Background Data. Investigators have suggested a significant correlation of osteopenia with adolescent idiopathic scoliosis. Because one half of the skeletal mass is acquired during the adolescent years, it is of importance to know whether the osteopenia is transient or persistent. Methods. Using dual-energy x-ray absorptiometry, bone mineral density of bilateral proximal femurs was studied longitudinally in 70 healthy control subjects and 14 patients with adolescent idiopathic scoliosis with significant osteopenia more than 2 standard deviations below the mean normal value. Results. The 14 girls with osteopenic adolescent idiopathic scoliosis who were followed up longitudinally for up to 3 years showed persistent and significantly lower bone mineral density when compared with normal age-, sex- and maturity-matched control subjects. Conclusions. Patients with adolescent idiopathic scoliosis are at increased risk of osteoporosis than are healthy adolescents. The lower rate of increase of bone mineral density in patients with adolescent idiopathic scoliosis who have low bone mineral density could predict a significantly lower peak bone mass in adulthood with all the associated problems of osteoporosis. Further investigation is needed to define whether osteopenia-associated scoliosis has the same cause, pathogenetic mechanism, and risk of progression when compared with adolescent scoliosis without osteopenia.