van Royen Barend J, Scheerder Famke J, Jansen Eric, Smit Theo H
Department of Orthopaedic Surgery, VU University Medical Center, P.O. Box 7057, 1007, MB Amsterdam, The Netherlands.
Eur Spine J. 2007 Sep;16(9):1445-9. doi: 10.1007/s00586-007-0371-5. Epub 2007 Apr 18.
A closing wedge osteotomy of the lumbar spine may be considered to correct posture and spinal balance in progressive thoracolumbar kyphotic deformity caused by ankylosing spondylitis (AS). Adequate deformity planning is essential for reliable prediction of the effect of surgical correction of the spine on the sagittal balance and horizontal gaze of the patient. The effect of a spinal osteotomy on the horizontal gaze is equal to the osteotomy angle. However, the effect of a spinal osteotomy on the sagittal balance depends on both the correction angle and the level of osteotomy simultaneously. The relation between the correction angle, the level of osteotomy and the sagittal balance of the spine can be expressed by a mathematical equation. However, this mathematical equation is not easily used in daily practice. We present the computer program ASKyphoplan that analyses and visualizes the planning procedure for sagittal plane corrective osteotomies of the spine in AS. The relationship between the planned correction angle, level of osteotomy and sagittal balance are coupled into the program. The steps taken during an ASKyphoplan run are outlined, and the clinical application is discussed. The application of the program is illustrated by the analysis of the data from a patient recently treated by a lumbar osteotomy in AS. The software can be used free of charge on the internet at http://www.stega.nl under the heading "research" in the menu.
对于强直性脊柱炎（AS）所致的进行性胸腰椎后凸畸形，可考虑行腰椎闭合楔形截骨术以纠正姿势和脊柱平衡。充分的畸形规划对于可靠预测脊柱手术矫正对患者矢状面平衡和水平注视的效果至关重要。脊柱截骨术对水平注视的影响等同于截骨角度。然而，脊柱截骨术对矢状面平衡的影响同时取决于矫正角度和截骨水平。矫正角度、截骨水平与脊柱矢状面平衡之间的关系可用一个数学方程表示。然而，这个数学方程在日常实践中并不容易使用。我们展示了计算机程序ASKyphoplan，它能分析并可视化AS患者脊柱矢状面矫正截骨术的规划过程。计划的矫正角度、截骨水平与矢状面平衡之间的关系被编入该程序。概述了ASKyphoplan运行过程中的步骤，并讨论了其临床应用。通过分析一名近期接受AS腰椎截骨术治疗患者的数据来说明该程序的应用。该软件可在互联网上免费使用，网址为http://www.stega.nl，在菜单的“研究”项下。
