The Effects of Intersegmental Compression on the 3-D Correction of Idiopathic Scoliosis Using Thoracoscopic Surgery

STUDY DESIGN Retrospective study. PURPOSE To investigate whether intersegmental compression can affect the results of threedimensional correction for idiopathic scoliosis. OVERVIEW OF LITERATURE Intersegmental compression is usually performed to increase the correction rate and enhance kyphosis restoration. However, it is presumed that the risk of decompensation is increased. METHODS Twenty-seven patients with idiopathic scoliosis who were corrected thoracoscopically were divided into two groups: a compression group and a non-compression group. Thoracic and lumbar scoliotic Cobb angles were measured pre-operatively, one week postoperatively, and at last follow-up. Changes in thoracic kyphosis and in sagittal and coronal balance were compared. RESULTS The average correction rates for thoracic scoliotic curves were 70.3% and 58.8% in the compression and non-compression groups, respectively (p=0.023), at 1 week postoperatively. However, these changed to 62.6% and 58.1% at the final follow-up visit (p=0.381). Thoracic kyphosis increased by 37.4% in the compression group and 20.9% in the non-compression group at 1 week postoperatively (p=0.435). Finally, thoracic kyphosis increased by 59.9% and 42.6%(p=0.473), respectively, at final follow-up. Axial rotation was corrected by 45.3% and 24.7% in the compression and non-compression groups, respectively (p=0.214). There were no significant differences in postoperative changes in coronal and sagittal balance between the two groups. CONCLUSIONS Three-dimensional correction by intersegmental compression tended to produce better results, especially during the early postoperative period. However, at final follow-up, no significant differences were observed between the two groups in terms of three-dimensional correction. Thus, we conclude that intersegmental compression is not always necessary for thoracoscopic scoliosis correction.