The study of development of new simulation system for corrective surgeries for spinal defurmity

已经进行了各种脊柱侧凸的脊柱器械手术。然而，由于脊柱侧凸是一种三维畸形，因此通常难以为特定患者选择最佳手术。本研究的目的是使用具有椎间盘、椎体和肋骨架的力学特性的三维数学模型来模拟脊柱侧凸的手术矫正。术前采用双平面X线摄影测量三维测量脊柱形状。通过轴向牵引下拍摄的X线片，计算材料补偿系数。使用该模型，我们模拟了23例平均Cobb角为52 °的脊柱侧凸矫正手术。术后平均Cobb角常规X线片为28.5 °，模拟X线片为28.3 °。两者平均相差6.0度。对于脊柱后凸，常规X线片为14.2度，模拟为19.2度。两种测量方法的平均差值为7.4度。在轴向旋转中，术后旋转角度为12.3度（计算机断层扫描）和9.7度（模拟）。两种方法之间的平均差异为3.6度。内固定手术的矫正效果可以使用我们的模拟模型进行三维预测。该模型被用于器械手术的实际使用。

Various spinal instrumentation surgery for scoliosis have been carried out. However, since scoliosis is a three-dimensional deformity, it is frequently difficult to select an optimum surgery for a particular patient. The purpose of this study is to simulate surgical correction of scoliotic spine using a three-dimensional mathematical model having mechanical properties of the disc, the vertebral body, and the rib cage. Preoperative spinal shape was measured using bi-plane X-ray photogrammetry three-dimensionally. Material compensational coefficient of each patient was estimated by X-ray film taken under axial traction. Using this model, we simulated 23 corrective surgeries for scoliosis with average Cobb angle 52 degrees. Postoperative average Cobb angle was 28.5 degrees on conventional X-ray and 28.3 degrees by the simulation. The average difference of the two was 6.0 degrees. For kyphosis, 14.2 degrees on conventional X-ray and 19.2 degrees by the simulation. The average difference of two methods of measurement was 7.4 degrees. In axial rotation, postoperative rotation angle was 12.3 degrees using computed tomography and 9.7 degrees by the simulation. The average difference between two methods was 3.6 degrees. The corrective effect of the instrumentation surgery could be predicted three-dimensionally using our simulation model. The model was put to practical use for the instrumentation surgery.