Mao Jennifer Z, Agyei Justice O, Ghannam Moleca M, Khan Asham, Christensen Marc, Meyers Joshua E, Pollina John, Mullin Jeffrey P
Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York.
Oper Neurosurg (Hagerstown). 2021 Mar 15;20(4):E312-E313. doi: 10.1093/ons/opaa412.
Traditionally, lateral mass screws (LMSs) have been the mainstay of posterior fixation in the subaxial spine. Although LMSs provide adequate fixation, cervical pedicle screws (CPSs) facilitate high fusion rates (90.5%) and provide for greater bone purchase, better reduction, lower rates of screw loosening or pull out, 2 times greater biomechanical advantage, superior stabilization, decreased development of pseudarthrosis, and decreased revision surgeries compared to LMSs.1-4 In addition, CPSs can be a powerful bail-out option after lateral mass construct failure. Navigation-guided CPS placement has been reported to have an accuracy of 90.3%.5 Navigation has the added advantage of mitigating screw malposition for the placement of CPS because of the smaller pedicle sizes and variability in cervical anatomy.1,3,6 The potential risks of subaxial CPS placement include the risks of vertebral artery injury, spinal cord injury, and injury to adjacent neurovasculature.2 The overall radiographic breach rate with intraoperative imaging is reported to range from 2.9% of 22.9%, with the majority of breaches occurring in the lateral direction.7,8 Despite radiographic breaches, the occurrence of nerve root injury (0.31% per screw), vertebral artery injury (0.15% per screw), and spinal cord injury (0% per screw) is rare.3,7 Here, we demonstrate navigation-assisted C1-C2 posterior fusion, with combined C1 LMSs and C2 pedicle screws with subaxial pedicle screw revision of prior failed instrumentation.3 The patient gave informed consent for surgery and video recording. Institutional review board approval was deemed unnecessary.
传统上,侧块螺钉一直是下颈椎后路固定的主要方式。尽管侧块螺钉能提供足够的固定,但颈椎椎弓根螺钉能实现更高的融合率(90.5%),且能获得更多骨质、实现更好的复位、降低螺钉松动或拔出率,相比侧块螺钉具有两倍的生物力学优势、更强的稳定性、减少假关节形成以及减少翻修手术。1-4此外,在侧块结构失败后,颈椎椎弓根螺钉可以作为一种有效的补救选择。据报道,导航引导下颈椎椎弓根螺钉置入的准确率为90.3%。5由于椎弓根尺寸较小且颈椎解剖结构存在变异性,导航在颈椎椎弓根螺钉置入时还具有减少螺钉位置不当的额外优势。1,3,6下颈椎椎弓根螺钉置入的潜在风险包括椎动脉损伤、脊髓损伤以及对相邻神经血管结构的损伤。2据报道,术中影像显示的总体影像学突破率在2.9%至22.9%之间,大多数突破发生在外侧。7,8尽管存在影像学突破,但神经根损伤(每枚螺钉0.31%)、椎动脉损伤(每枚螺钉0.15%)和脊髓损伤(每枚螺钉0%)的发生率很低。3,7在此,我们展示了导航辅助下的C1-C2后路融合术,采用C1侧块螺钉和C2椎弓根螺钉联合,并对先前失败的内固定进行下颈椎椎弓根螺钉翻修。3患者已签署手术及录像知情同意书。机构审查委员会认为无需批准。