A novel cervical MRI-vertebral bone quality score system for assessment of bone density in LenKe 5/6 type adolescent idiopathic scoliosis

Abstract

Aim

To explore the application of the cervical vertebral bone quality (C-VBQ) score based on MRI in assessing bone mineral density (BMD) in LenKe 5/6 type adolescent idiopathic scoliosis (AIS) patients.

Materials and Methods

Lenke 5/6 AIS patients were retrospectively included between January 2016 and January 2024 and then were divided into normal and low BMD groups according to quantitative computed tomography (QCT). The VBQ scores and HU values were measured from MRI and CT. Three types of C-VBQs were obtained through different calculation methods, namely C-VBQ1/2/3. The correlations between QCT Z-score and C-VBQ scores/HU value were analyzed with Pearson correlation and linear regression. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic accuracy of C-VBQs and HU.

Results

One hundred and forty patients (52 in the normal group, 88 in the low BMD group) were included. Significant differences in HU value, C-VBQ1 and C-VBQ3 were found between groups. HU value, C-VBQ1 and C-VBQ3 were all significantly correlated to QCT Z-score (correlation coefficient (r): HU: 0.704, C-VBQ1: -0.493, C-VBQ3: -0.391, P<0.001). The area-under-curve (AUC) of the ROC curve was calculated (HU: 0.816, C-VBQ1: 0.79, C-VBQ3: 0.701). The AUC of the combination of C-VBQ1 and HU value was 0.851. According to the Youden index, when a cutoff value was set at 326.37, 3.325 and 3.16 respectively, HU value, C-VBQ1 and C-VBQ3 had the best diagnosis performance in distinguishing low BMD.

Conclusion

The cervical-VBQ score was a promising tool in distinguishing low BMD in Lenke 5/6 type AIS patients and could be useful as opportunistic assessment for screening and complementary evaluation before surgery.