Paramore C G, Dickman C A, Sonntag V K
Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
J Neurosurg. 1996 Aug;85(2):221-4. doi: 10.3171/jns.1996.85.2.0221.
Posterior transarticular screw fixation of the C1-2 complex has become an accepted method of rigid internal fixation for patients requiring posterior C1-2 fusion. The principal limitation of this procedure is the location of the vertebral artery, because an anomalous position may prohibit screw placement. In this study, a consecutive series of computerized tomography (CT) scans was reviewed, and the suitability of each patient for transarticular screw fixation was evaluated. All of the fine-slice axial C1-2 CT scans and reconstructions performed on a spiral scanner over 2 years were reviewed. A novel screw trajectory reconstruction was designed to visualize the potential path of a transarticular screw in the plane of the reconstruction. Scans were reviewed for bone anatomy and the position of the transverse foramen. Seventeen (18%) of 94 patients had a high-riding transverse foramen on at least one side of the C-2 vertebra that would prohibit the placement of transarticular screws. The left side was involved in nine patients and the right in five. Three patients had bilateral anomalies. The mean age of the group with anomalies (35.9 years, range 10-76) was not significantly different from the overall mean age (35.7 years, range 6-94). An additional five patients (5%) were considered to have anatomy in which screw placement was feasible but risky. On the basis of these data, it is postulated that 18% to 23% of patients may not be suitable candidates for posterior C1-2 transarticular screw fixation on at least one side.
对于需要进行C1-2后路融合的患者，C1-2复合体的后路经关节螺钉固定已成为一种被认可的坚强内固定方法。该手术的主要限制因素是椎动脉的位置，因为其位置异常可能会妨碍螺钉置入。在本研究中，回顾了一系列连续的计算机断层扫描（CT），并评估了每位患者行经关节螺钉固定的适用性。回顾了在2年期间使用螺旋扫描仪进行的所有C1-2薄层轴向CT扫描及重建图像。设计了一种新颖的螺钉轨迹重建方法，以在重建平面上可视化经关节螺钉的潜在路径。对扫描图像进行骨骼解剖结构及横突孔位置的评估。94例患者中，17例（18%）在C2椎体至少一侧存在高位横突孔，这将妨碍经关节螺钉的置入。左侧有9例患者受累，右侧有5例。3例患者双侧存在异常。存在异常的患者组平均年龄（35.9岁，范围10-76岁）与总体平均年龄（35.7岁，范围6-94岁）无显著差异。另外5例患者（5%）被认为其解剖结构使螺钉置入可行但存在风险。基于这些数据，推测至少有18%至23%的患者可能不适合进行C1-2后路经关节螺钉固定。
