Główka Paweł, Politarczyk Wojciech, Janusz Piotr, Woźniak Łukasz, Kotwicki Tomasz
Department of Spine Disorders and Pediatric Orthopedics, Poznan University of Medical Sciences, 28 Czerwca 1956 135/147, 61-545, Poznan, Poland.
Institute of Mathematics, Warsaw University, Banacha 2, 02-097, Warsaw, Poland.
BMC Musculoskelet Disord. 2020 Jul 21;21(1):475. doi: 10.1186/s12891-020-03494-w.
Three-dimensional idiopathic scoliosis cannot be accurately assessed with the aid of a single plane parameter - the Cobb angle. We propose a novel method for evaluating the three-dimensional (3D) pattern of scoliosis based on two X-rays (PA and lateral). The proposed method consists of the measurements of the angles between the upper endplate of the upper-end vertebra and the lower endplate of the lower-end vertebra (3D scoliosis angle).
The 3D-angles of thirty scoliosis curves were measured with either computed tomography (CT) or digitally reconstructed radiographs (DRRs): PA and lateral. CT was used as a reference. In the case of CT, the 3D angle was calculated based on the coordinates of three points situated on the upper endplate and those of three points situated on the lower endplate of the scoliosis curve. In the case of the DRR, the 3D angle was calculated using the four-angle method: the angles formed by the endplates of the curve with the transverse plane. The results were tested with the Student's t-test, and the agreement of measurements was tested with the intraclass correlation coefficient.
There was no significant difference between the 3D-angle measurements obtained with DRRs versus CT, p > 0.05. There was, however, a significant difference between the 3D-scoliosis angle and the Cobb angle measurements performed based on the X-rays. The reproducibility and reliability of 3D angle measurements were high.
Based on two standard radiographs, PA and lateral, it is possible to calculate the 3D scoliosis angle. The proposed method facilitates 3D-scoliosis assessment without the use of sophisticated devices. Considering the 3D nature of AIS, the 3D parameters of the spine may help to apply a more effective treatment and estimate a more precise prognosis for patient with scoliosis.
借助单一平面参数—— Cobb 角无法准确评估三维特发性脊柱侧凸。我们提出一种基于两张 X 光片（正位和侧位）评估脊柱侧凸三维模式的新方法。所提出的方法包括测量上端椎上终板与下端椎下终板之间的角度（三维脊柱侧凸角）。
使用计算机断层扫描（CT）或数字重建射线照片（DRR）（正位和侧位）测量 30 条脊柱侧凸曲线的三维角度：以 CT 作为参考。对于 CT，基于位于脊柱侧凸曲线上终板的三个点和下终板的三个点的坐标计算三维角度。对于 DRR，使用四角法计算三维角度：曲线终板与横断面形成的角度。结果采用 Student's t 检验进行测试，测量的一致性采用组内相关系数进行测试。
DRR 与 CT 获得的三维角度测量值之间无显著差异，p > 0.05。然而，三维脊柱侧凸角与基于 X 光片进行的 Cobb 角测量值之间存在显著差异。三维角度测量的可重复性和可靠性很高。
基于两张标准 X 光片，正位和侧位，可以计算三维脊柱侧凸角。所提出的方法无需使用复杂设备即可促进三维脊柱侧凸评估。考虑到 AIS 的三维性质，脊柱的三维参数可能有助于为脊柱侧凸患者应用更有效的治疗方法并估计更精确的预后。
