van Royen Barend J
Department of Orthopaedic Surgery, Amsterdam UMC, Vrije Universiteit and University of Amsterdam, Amsterdam Movement Sciences, Amsterdam, the Netherlands.
Orthop Res Rev. 2020 Nov 17;12:171-182. doi: 10.2147/ORR.S275860. eCollection 2020.
Ankylosing spondylitis (AS) may cause a severe rigid thoracolumbar kyphotic deformity (TLKD) that leads to considerable disturbances of posture and spinal balance. In few patients, a corrective osteotomy of the lumbar spine may be considered. Preoperative planning of a lumbar osteotomy for correction of a severe TLKD due to AS is important to correct patient's sagittal balance and view angle. There is a need for accurate preoperative planning that can be used easily in daily practice.
The basic biomechanical and mathematical principles of preoperative planning for correction of a TLKD due to AS are described. A search was performed for free available computer programs that can be used for pre-operative planning of spinal osteotomies in AS. Finally, the use of these computer programs is illustrated and described.
Sagittal balance is measured on a standing lateral full-length radiograph of the spine. The assessment of the pelvic parameters (PI, PT, SS) in conjunction with sagittal vertical axis (SVA) and chin-brow-to-vertical angle (CBVA) provides a comprehensive picture of the sagittal spinal alignment and compensatory mechanisms of the patient. The relation between the level of lumbar osteotomy and the amount of correction needed can be calculated with different elementary trigonometric equations. Two free available computer programs, ASKyphoplan and Surgimap, are illustrated and described that can be used for pre-operative planning of spinal osteotomies in AS.
Preoperative planning of the lumbar osteotomy in AS involves assessment of the combined effect of location of the osteotomy, amount of bone resection, SVA, CBVA, and pelvic parameters. Two free available computer programs, ASKyphoplan and Surgimap, are easy to use in clinical practice to predict postoperative sagittal balance of lumbar osteotomies in patients with severe TLKD due to AS.
强直性脊柱炎（AS）可能导致严重的胸腰椎后凸僵硬畸形（TLKD），进而引起姿势和脊柱平衡的显著紊乱。在少数患者中，可考虑进行腰椎截骨矫正术。对于因AS导致的严重TLKD进行腰椎截骨术前规划，对于纠正患者的矢状面平衡和视角至关重要。需要一种准确的术前规划方法，以便在日常实践中轻松使用。
描述了因AS导致的TLKD矫正术前规划的基本生物力学和数学原理。搜索了可免费获取的计算机程序，这些程序可用于AS患者脊柱截骨术的术前规划。最后，对这些计算机程序的使用进行了说明和描述。
矢状面平衡通过脊柱站立位全长侧位X线片测量。结合矢状垂直轴（SVA）和眉-垂直线角（CBVA）评估骨盆参数（PI、PT、SS），可全面了解患者的矢状面脊柱排列和代偿机制。腰椎截骨水平与所需矫正量之间的关系可用不同的基本三角方程计算。展示并描述了两个可免费获取的计算机程序ASKyphoplan和Surgimap，它们可用于AS患者脊柱截骨术的术前规划。
AS患者腰椎截骨术前规划包括评估截骨位置、骨切除量、SVA、CBVA和骨盆参数的综合影响。两个可免费获取的计算机程序ASKyphoplan和Surgimap在临床实践中易于使用，可预测因AS导致严重TLKD患者腰椎截骨术后的矢状面平衡。
