Cervical sagittal alignment in adolescent idiopathic scoliosis patients (Lenke type 1-6)

We collected the radiographic and clinical data of 129 AIS patients (Lenke type 1-6) to analyze the characteristics of cervical sagittal alignment in adolescent idiopathic scoliosis patients and the correlations between cervical sagittal alignment and global sagittal alignment, and clinical symptoms.

129 patients with AIS and 48 adolescent volunteers were included in this study. The angles of the main thoracic curve, proximal thoracic curve, thoracolumbar curve, lumbar curve, C2-7 Cobb angle, T5-12 Cobb angle, L1-5 Cobb angle, pelvic incidence, pelvic tilt, sacrum slop, C2-7 sagittal vertical axis, C7-S1 sagittal vertical axis, and T1 pelvic angle were included in radiographic measurements. In addition, a 10-cm Visual Analogue Score was used to assess neck pain. Pearson correlation coefficients and t-test were used for statistical analysis.

In the AIS group, C2-7 Cobb angle increased significantly compared with the control group, and it was significantly correlated with T5-12 Cobb angle and L1-5 Cobb angle. There was no significant correlation between C2-7 Cobb angle and coronal curvature in each Lenke type of patients. In the C2-7 SVA ≥ 3 cm group, C2-7 Cobb angle was related to T5-12 Cobb angle, L1-5 Cobb angle, pelvic incidence, and sacrum slop. In the cervical kyphosis group, T5-12 Cobb angle was significantly lower than that of the C2-7 Cobb angle ≥0 group. The C2-7 Cobb angle in the group with T5-12 Cobb angle >30° increased significantly compared with that in the group with T5-12 Cobb angle ≤30°. The Visual Analogue Score of neck pain of the cervical imbalance group was significantly higher than that of the cervical balance group.

The cervical sagittal alignment in AIS patients was related with thoracic kyphosis and lumbar lordosis, especially with thoracic kyphosis, but not with the coronal angle of thoracic and lumbar spine, and pelvic parameters.