Gabriel Daniel C, Gonzalez Marcos R, Lee Sang W, Lange Jeffrey K, Chen Antonia F
Harvard Medical School, Boston, Massachusetts.
Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
J Arthroplasty. 2025 Oct;40(10):2763-2770. doi: 10.1016/j.arth.2025.04.063. Epub 2025 May 7.
Despite the growing use of computer-navigated and robotic-assisted total hip arthroplasty (THA), uncertainty remains regarding their outcomes compared with manual THA. Therefore, we implemented the concept of reverse fragility index (RFI) to assess the statistical robustness of available randomized controlled trials (RCTs) designed to study comparative revision rates between manual and technology-assisted THA.
The RCTs reporting revision rates for manual and robotic-assisted/computer-navigated THA were included in our systematic review. Our search included all RCTs published until February 2, 2025. There were nine RCTs with 894 patients analyzed. The RFI, defined as the minimum number of event reversals necessary to change a nonsignificant result to statistically significant, was calculated for each study using a threshold of P < 0.05. The reverse fragility quotient (RFQ), which adjusts the RFI relative to the study sample, was additionally calculated.
The median RFI was five (interquartile range [IQR], 4 to 5) for both computer-navigated and robotic-assisted THA subgroups, meaning that a median of five events would be needed to change the results from nonsignificant to significant. The median RFQ was 0.045 (IQR, 0.036 to 0.083), indicating that an event reversal in 4.5% of patients would be sufficient to make the results significant. The median number of patients lost to follow-up was six (IQR, 0 to 41). Of the nine studies, seven (78%) had a loss to follow-up greater than or equal to its RFI.
We observed significant statistical fragility in all included RCTs that compared revision rates of manual versus technology-assisted THA. We recommend routine reporting of RFI and RFQ metrics in future RCTs with nonsignificant findings as well as careful interpretation of P values.
II.
尽管计算机导航和机器人辅助全髋关节置换术（THA）的应用越来越广泛，但与手动THA相比，其疗效仍存在不确定性。因此，我们引入了反向脆弱性指数（RFI）的概念，以评估旨在研究手动与技术辅助THA比较翻修率的现有随机对照试验（RCT）的统计稳健性。
我们的系统评价纳入了报告手动与机器人辅助/计算机导航THA翻修率的RCT。我们的检索包括截至2025年2月2日发表的所有RCT。共分析了9项RCT中的894例患者。使用P<0.05的阈值为每项研究计算RFI，即把无统计学意义的结果转变为有统计学意义所需的最小事件反转数。此外，还计算了反向脆弱性商数（RFQ），它是相对于研究样本对RFI进行调整。
计算机导航和机器人辅助THA亚组的RFI中位数均为5（四分位间距[IQR]，4至5），这意味着中位数为5个事件才能将结果从无统计学意义转变为有统计学意义。RFQ中位数为0.045（IQR，0.036至0.083），表明4.5%的患者发生事件反转就足以使结果有统计学意义。失访患者的中位数为6例（IQR，0至41）。在9项研究中，7项（78%）的失访率大于或等于其RFI。
我们观察到，在所有比较手动与技术辅助THA翻修率的纳入RCT中，均存在显著的统计脆弱性。我们建议在未来结果无统计学意义的RCT中常规报告RFI和RFQ指标，并谨慎解读P值。
II级
