Cervical and Thoracic Sagittal Curves in Thoracic Adolescent Idiopathic Scoliosis

Abstract

Materials a and M Methods: The sagittal curves were analyzed in normal adolescents (N-adol group, n=23) and patients with thoracic AIS (AIS group, n=26) who had thoracic curves ≥ 45� . Lateral standing radiographs of the cervical spine with a elbow straight and the whole spine with the hands on the clavicles were taken. The sagittal curves and balance were measured in the following segments; C2-C7, T2-T5, T5-12, T2-12, T12-S1. Cervical lordosis (C2-C7) was measured in both cervical spine radiographs and whole spine radiographs. Results: In the N-adol group, the cervical lordosis was 9.2±14.6�in the cervical spine radiographs and -0.6±12.9�(‘-’ means kyphosis) in whole spine radiographs. In the AIS group, cervical lordosis was -5.0±12.9�in the cervical radiographs and -8.1± 12.7�in the whole radiographs. The AIS group had significantly less cervical lordosis than the N-adol group. Thoracic kyphosis of T5-12 and T2-12 was 24.1±10.6�and 38.9±13.1�in the N-adol group, respectively, and 17.8±9.4�and 30.1±11.8�in the AIS group, respectively. There was a significant difference between the two groups (Ps 0.05). In the AIS group, the cervical lordosis measured in the cervical spine radiograph showed a positive correlation with thoracic kyphosis of T2-5 (r=0.50, P=0.009) and T2-12 (r=0.57, P=0.003). Conclusions: AIS patients had significantly less cervical lordosis and thoracic kyphosis than normal adolescents. Decreased cervical lordosis in AIS had a significant correlation with their relative thoracic hypokyphosis.