He Qiang, Sun Caihong, Ma Jianbing, Guo Jianbing
Department of Orthopaedic Surgery, Hong-Hui Hospital, Xi'an Jiaotong University Health Science Center, No. 555 East Youyi Road, Xi'an, 710054, China.
Department of Informatics, 451 Hospital of PLA, No. 269 East Youyi Road, Xi'an, 710054, China.
Arthroplasty. 2020 Jan 29;2(1):3. doi: 10.1186/s42836-020-0025-1.
Measured resection and gap balancing are two distinct methods for proper femoral component alignment in total knee arthroplasty. Decision-making between the two techniques is controversial. The aim of this systematic review and meta-analysis was to compare measured resection and gap balancing with regard to the radiological and clinical benefits, and to examine whether this change the conclusions from previous trails.
A systematic literature search of the medical literature from January 1990 to February 2015 was performed. We selected six randomized controlled trials and five prospective cohort studies comparing gap balancing and measured resection in patients undergoing primary total knee arthroplasty. Data from included studies were pooled with use of fixed-effects and random-effects models with standard mean differences and risk ratios for continuous and dichotomous variables, respectively. Heterogeneity across studies was assessed with calculation of the I statistic.
A total of 857 knees from 11 trials were included. Four hundred and forty-one knees were treated with gap balancing and 416 were treated with measured resection. In contrast to previous studies, we found that gap balancing demonstrated better patient-reported outcomes with regard to Knee Society score for pain (WMD 2.75, p = 0.004) and Knee Society score for function (WMD 5.47, p < 0.0001) at two-year follow-up. Gap balancing showed more precise limb alignment in terms of post-operative value of mechanical axis (WMD 0.40°, p = 0.01) and risk of mechanical alignment outliers (RR 0.350, p < 0.0001). However, gap balancing was associated with more joint line elevation (WMD 1.27 mm, p < 0.0001) and longer operative time (WMD 16.18 min, p < 0.0001). No significant difference was observed in rotation of the femoral component (p = 0.07).
The meta-analysis demonstrated that gap balancing was able to achieve more precise coronal alignment with better short-term patient-reported outcomes compared with measured resection. Measured resection was more desirable than gap balancing with regard to restoration of the joint line and operative time. Comparable femoral rotational alignment was observed.
在全膝关节置换术中，测量截骨和间隙平衡是两种不同的实现股骨假体正确对线的方法。在这两种技术之间进行决策存在争议。本系统评价和荟萃分析的目的是比较测量截骨和间隙平衡在影像学和临床方面的益处，并检验这是否会改变既往研究的结论。
对1990年1月至2015年2月的医学文献进行系统检索。我们选择了六项随机对照试验和五项前瞻性队列研究，比较初次全膝关节置换患者的间隙平衡和测量截骨。纳入研究的数据分别采用固定效应模型和随机效应模型进行合并，连续变量采用标准均数差，二分变量采用风险比。通过计算I统计量评估研究间的异质性。
共纳入11项试验的857个膝关节。441个膝关节采用间隙平衡治疗，416个膝关节采用测量截骨治疗。与既往研究不同，我们发现，在两年随访时，间隙平衡在膝关节协会疼痛评分（加权均数差2.75，p = 0.004）和膝关节协会功能评分（加权均数差5.47，p < 0.0001）方面显示出更好的患者报告结局。间隙平衡在机械轴术后值（加权均数差0.40°，p = 0.01）和机械对线异常值风险（风险比0.350，p < 0.0001）方面显示出更精确的肢体对线。然而，间隙平衡与更多的关节线抬高（加权均数差1.27 mm，p < 0.0001）和更长的手术时间（加权均数差16.18分钟，p < 0.0001）相关。股骨假体旋转方面未观察到显著差异（p = 0.07）。
荟萃分析表明，与测量截骨相比，间隙平衡能够实现更精确的冠状面对线，且短期患者报告结局更好。在恢复关节线和手术时间方面，测量截骨比间隙平衡更可取。观察到股骨旋转对线相当。
