Bone mineral density of girls with idiopathic scoliosis: a comparative study

Several studies have suggested higher incidence of osteoporosis in patients with idiopathic scoliosis in comparison with the normal population. The aim of this study was to assess the prevalence of low bone mass among adolescent girls with idiopathic scoliosis. In this cross-sectional study performed in shafa Hospital in Tehran, Iran during 2011-2012, we recruited fifty-seven 12- to-20-year old girls with idiopathic scoliosis and compared them with 100 age-matched healthy girls. The patients had no other diseases including neuromuscular disorders, congenital vertebral anomalies or a history of spinal surgery. Bone mineral densities (BMD) of the hip and spine were evaluated and compared in all 157 participants using dual X-ray absorptiometry (DXA). Standard BMD (sBMD) was also calculated at the lumbar spine. Analysis of the data revealed that hip BMD was significantly (P=0.004) lower in patients with idiopathic scoliosis versus the controls. Moreover, BMD and sBMD of the Spine were also significantly lower in the patients (respectively, P=0.030 and P=0.030). Curve location had no effect on the values of hip BMD, spine BMD or spine sBMD (respectively, P=0.061 and P=0.274 and P=0.208).Finally, with more severe curves a lower bone mass was detected for sBMD and spine BMD (respectively, P=0.017 and P=0.016), but it was not significant for hip BMD (P=0.069). Adolescent girls with idiopathic scoliosis had lower bone mass compared with their healthy peers. The lower bone mass was correlated with the severity of the curve but not its location.