The Sagittal Alignment of the Cervical Spine in Adolescent Idiopathic Scoliosis

The purpose of this study is to examine the sagittal alignment of cervical spine in adolescent idiopathic scoliosis with lateral radiographs of cervical spine. Cervical alignment of the 110 adolescent idiopathic scoliosis patients was measured by Cobb angle from C2 to C6, and thoracic kyphosis was measured from T2 to T12 with the lateral full-spine radiographs. The average sagittal alignment was 5.7 degrees of kyphosis for cervical spine, and 22.3 degrees of lordosis for thoracic spine. Seventy-seven of the 110 patients (70%) had cervical kyphosis, which is much higher than that of the previous reports examined normal adults. The average alignment of the thoracic spine in the patients with and without cervical kyphosis was 19.8 degrees and 28.0 degrees respectively. This difference was statistically significant (p<0.001). This result suggests that loss of thoracic kyphosis in idiopathic scoliosis may interfare with the alignment of cervical spine.