Correlation Study of Overall and Apical Vertebral Bone Mineral Density With the Major Curve in Adolescent Idiopathic Scoliosis.

Abstract

Retrospective study. To investigate the correlation between overall and apical vertebral bone mineral density (BMD) concerning the severity of the major curve in patients with adolescent idiopathic scoliosis (AIS). Patients with AIS experience systemic bone metabolic issues, and reduced whole-body BMD may influence the progression of scoliosis. The relationship between local BMD and the severity of scoliosis remains unclear. Eighty-one patients with AIS were analyzed retrospectively. Demographic data, including age, sex, weight, height, and body mass index (BMI), BMD of the lumbar spine and hip, and CT Hounsfield unit (HU) values of the apical vertebra were collected. The apical vertebral translation (AVT) was measured using whole-spine posteroanterior X-rays. The HU value of the region of interest of the apical vertebra was measured in the horizontal position, scanned along the pedicle. In the apical vertebra, the HU values for both the normal bone mineral density (BMD) group and the less-than-expected BMD group, as well as those for the convex and concave sides, demonstrated statistically significant differences (P<0.05). Furthermore, significant differences in the Cobb angle of the major curve were observed between the 2 groups (P<0.05). The HU values of the apical vertebra, along with its concave and convex sides, exhibited a moderate positive correlation with the lowest Z-score. However, no significant correlation was identified between the HU values of the concave side of the apical vertebra and the Cobb angle (P>0.05). In addition, the CT HU values of the apical vertebra and its convex side displayed a weak negative correlation with the Cobb angle. The CT HU values of the convex side of the apical vertebra also indicated a weak negative correlation with the AVT. Patients with lower overall BMD exhibit more severe major curve. In addition, a significant correlation exists between the BMD of the apical vertebra and the severity of the major curve.