Systematic review and meta-analysis. The purpose of this study was to compare the safety and accuracy of the C2 pedicle versus C2 pars screws placement and free-hand technique versus navigation for upper cervical fusion patients. Databases searched included PubMed, Scopus, Web of Science, and Cochrane Library to identify all papers published up to April 2020 that have evaluated C2 pedicle/pars screws placement accuracy. Two authors individually screened the literature according to the inclusion and exclusion criteria. The accuracy rates associated with C2 pedicle/pars were extracted. The pooled accuracy rate estimated was performed by the CMA software. A funnel plot based on accuracy rate estimate was used to evaluate publication bias. From 1123 potentially relevant studies, 142 full-text publications were screened. We analyzed data from 79 studies involving 4431 patients with 6026 C2 pedicle or pars screw placement. We used the Newcastle-Ottawa Scale (NOS) to evaluate the quality of studies included in this review. Overall, funnel plot and Begg’s test did not indicate obvious publication bias. The pooled analysis reveals that the accuracy rates were 93.8% for C2 pedicle screw free-hand, 93.7% for pars screw free-hand, 92.2% for navigated C2 pedicle screw, and 86.2% for navigated C2 pars screw (all, P value < 0.001). No statistically significant differences were observed between the accuracy of placement C2 pedicle versus C2 pars screws with the free-hand technique and the free-hand C2 pedicle group versus the navigated C2 pedicle group (all, P value > 0.05). Overall, there was no difference in the safety and accuracy between the free-hand and navigated techniques. Further well-conducted studies with detailed stratification are needed to complement our findings.

中文翻译：

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C2椎弓根或椎弓根螺钉放置的准确性和安全性：系统的回顾和荟萃分析。

系统评价和荟萃分析。这项研究的目的是比较上颈椎融合患者的C2椎弓根与C2椎弓根螺钉放置以及徒手技术与导航的安全性和准确性。搜索的数据库包括PubMed，Scopus，Web of Science和Cochrane图书馆，以识别截至2020年4月发表的所有评估C2椎弓根/ pars螺钉放置准确性的论文。两位作者根据纳入和排除标准分别筛选了文献。提取与C2蒂/ pars相关的准确率。估计的合并准确率由CMA软件执行。基于准确率估计的漏斗图用于评估发布偏差。从1123篇潜在的相关研究中，筛选了142篇全文出版物。我们分析了79项研究的数据，涉及4431例6026 C2椎弓根或椎弓根螺钉置入的患者。我们使用纽卡斯尔-渥太华量表（NOS）评估了该评价中的研究质量。总体而言，漏斗图和Begg检验均未显示明显的出版偏倚。汇总分析显示，C2椎弓根螺钉徒手的准确性为93.8％，pars螺钉徒手螺钉的为93.7％，C2椎弓根螺钉的为92.2％，C2椎弓根螺钉的为86.2％（所有，P值< 0.001）。用徒手技术放置C2椎弓根螺钉与C2椎弓根螺钉的精度以及徒手操作的C2椎弓根螺钉组相对于导航C2椎弓根螺钉组的精度均未观察到统计学差异（所有，P值> 0.05）。总体，徒手和导航技术在安全性和准确性上没有差异。需要进一步进行详细分层的良好研究，以补充我们的发现。