THE SAGITTAL ALIGNMENT OF THE CERVICAL-SPINE IN ADOLESCENT IDIOPATHICSCOLIOSIS

To assess the sagittal orientation of the cervical and thoracolumbar s pine, 38 adolescents with idiopathic scoliosis were studied. The C7 pl umb line and Cobb angles from C2-6, T1-12, and L1-S1 were measured on preoperative films. Lateral radiographs with > 1-year follow-up after surgical correction were available for the same measurements in 28 pat ients. The preoperative curve from C2-6 was 6 +/- 11 degrees of kyphos is. There was a significant correlation between the loss of thoracic k yphosis and the development of cervical kyphosis for the entire group preoperatively (p = 0.009). Postoperatively, cervical kyphosis increas ed to 11 +/- 9 degrees at 1-year follow-up (p = 0.05). There was no pr ogression of cervical kyphosis in patients with ''thoracic hypokyphosi s'' (kyphosis <20 degrees). Cervical kyphosis increased in patients wi th ''normal'' thoracic kyphosis (20-40 degrees) and in patients with h yperkyphosis (kyphosis >40 degrees) after surgery, despite preservatio n of thoracolumbar sagittal contour. There were no significant differe nces between the sagittal contour of patients treated with Cotrel-Dubo usset or Harrington instrumentation.