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.