Wajanavisit Wiwat, Woratanarat Patarawan, Woratanarat Thira, Aroonjaruthum Kitti, Kulachote Noratep, Leelapatana Wajana, Laohacharoensombat Wichien
Department of Orthopedics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Thailand.
Indian J Orthop. 2010 Jan;44(1):28-34. doi: 10.4103/0019-5413.58603.
Selective thoracic fusion in type II curve has been recommended by King et al. since 1983. They suggested that care must be taken to use the vertebra that is neutral and stable so that the lower level of fusion is centered over the sacrum. Since then there has been the trend to do shorter and selective fusion of the major curve. This study was conducted to find out whether short posterior pedicle instrumentation alone could provide efficient correction and maintain trunk balance comparing to the anterior instrumentation.
A prospective study was conducted during 2005-2007 on 39 consecutive cases with idiopathic scoliosis cases King 2 and 3 (Lenke 1A, 1B), 5C and miscellaneous. Only the major curve was instrumented unless both curves were equally rigid and of the same magnitude. The level of fusion was planned as the end vertebra (EVB) to EVB fusion, although minor adjustment was modified by the surgeons intraoperatively. The most common fusion levels in major thoracic curves were T6-T12, whereas the most common fusion levels in the thoraco-lumbar curves were T10-L3. Fusion was performed from the posterior only approach and the implants utilized were uniformly plate and pedicle screw system. All the patients were followed at least 2 years till skeletal maturity. The correction of the curve were assessed according to type of curve (lenke IA, IB and 5), severity of curve (less than 450, 450-890 and more than 900), age at surgery (14 or less and 15 or more) and number of the segment involved in instrumentation (fusion level less than curve, fusion level as of the curve and fusion more than the curve)
The average long-term curve correction for the thoracic was 40.4% in Lenke 1A, 52.2% in Lenke 1B and 56.3% in Lenke 5. The factors associated with poorer outcome were younger age at surgery (<11 years or Risser 0), fusion at wrong levels (shorter than the measured end vertebra) and rigid curve identified by bending study. However, all patients had significant improved trunk balance and coronal hump at the final assessment at maturity. Two patients underwent late extension fusion because of junctional scoliosis.
With modern instrumentations, the EVB of the major curve can be used at the end of the instrumentation in most cases of idiopathic scoliosis. In those cases with either severe trunk shift, younger than 11 years old, or extreme rigid curve, an extension of one or more levels might be safer. In particular situations, the concept of centering the lowest vertebra over the sacrum should be adopted.
自1983年以来，金氏等人建议对II型曲线进行选择性胸椎融合。他们建议必须小心使用中立且稳定的椎体，以便融合的较低水平以骶骨为中心。从那时起，出现了对主要曲线进行更短和选择性融合的趋势。本研究旨在探讨单纯短节段后路椎弓根内固定与前路内固定相比，是否能提供有效的矫正并维持躯干平衡。
2005年至2007年对39例连续的特发性脊柱侧凸患者（金氏2型和3型，Lenke 1A、1B、5C及其他类型）进行了一项前瞻性研究。除非两条曲线同样僵硬且程度相同，否则仅对主要曲线进行内固定。融合水平计划为终椎（EVB）至EVB融合，不过术中外科医生会进行一些微调。主要胸椎曲线最常见的融合水平为T6 - T12，而胸腰段曲线最常见的融合水平为T10 - L3。仅通过后路进行融合，使用的植入物均为钢板和椎弓根螺钉系统。所有患者至少随访2年直至骨骼成熟。根据曲线类型（Lenke IA、IB和5）、曲线严重程度（小于45°、45° - 89°和大于90°）、手术年龄（14岁及以下和15岁及以上）以及内固定涉及的节段数（融合水平小于曲线、融合水平与曲线相同、融合水平大于曲线）评估曲线的矫正情况。
Lenke 1A组胸椎的平均长期曲线矫正率为40.4%，Lenke 1B组为52.2%，Lenke 5组为56.3%。与较差结果相关的因素包括手术年龄较小（<11岁或Risser 0级）、融合水平错误（短于测量的终椎）以及通过弯曲试验确定的僵硬曲线。然而，所有患者在成熟时的最终评估中躯干平衡和冠状面驼背均有显著改善。两名患者因交界性脊柱侧凸接受了二期延长融合。
使用现代内固定技术，在大多数特发性脊柱侧凸病例中，主要曲线的EVB可用于内固定结束时。在那些躯干严重移位、年龄小于11岁或曲线极度僵硬的病例中，延长一个或多个节段可能更安全。在特定情况下，应采用以最低椎体位于骶骨上方为中心的概念。
