Quality of evidence (GRADE).

Introduction
The aims of this review was to investigate the effectiveness of closed kinetic chain exercise (CKCE) on pain, function, and proprioception in individuals with knee osteoarthritis (OA).
Methods
Nine databases were searched up to December 2023. Randomized controlled trials (RCTs) examining the effects of CKCE in individuals with knee OA were included. The methodological quality was assessed using the PEDro scale, and the level of evidence was evaluated with the GRADE system. A random-effects meta-analysis was conducted to assess differences between treatment groups for the primary outcomes (pain and function). Effect sizes were calculated using standardized mean differences (SMDs) with 95% confidence intervals (CIs).
Results
A total of 24 studies were included in the descriptive analysis, and 18 studies were included in the quantitative analysis (meta-analysis). The meta-analysis results indicated that CKCE treatment led to greater improvements in pain (SMD = −0.76; 95% CI: −1.51, −0.01) and function (SMD = −1.25; 95% CI: −1.88, −0.62) compared to no treatment. A subgroup meta-analysis showed that the combined treatment of CKCE and conventional physical therapy (CPT) resulted in greater improvements in pain (SMD = −1.18; 95% CI: −1.70, −0.67) and function (SMD = −1.27; 95% CI: −1.79, −0.75) compared to CPT alone. The risk of bias assessment revealed that two studies were of low quality, nine were of fair quality, and the remaining 13 were of high quality. The GRADE system indicated a low quality of evidence for the effects of CKCE on both pain and function.
Conclusion
While CKCE shows promise in reducing pain and improving function in individuals with knee OA, the quality of evidence is considered low according to the GRADE system. Further high-quality RCTs with larger sample sizes are needed to confirm the effectiveness of CKCE in managing knee OA.

引言
本综述旨在探究闭链运动（closed kinetic chain exercise, CKCE）对膝骨关节炎（knee osteoarthritis, OA）患者疼痛、功能与本体感觉的改善效果。
方法
本研究检索了截至2023年12月的9个数据库，纳入探究闭链运动对膝骨关节炎患者干预效果的随机对照试验（randomized controlled trials, RCTs）。采用PEDro量表评估方法学质量，使用GRADE系统评价证据等级。通过随机效应模型开展荟萃分析，以评估治疗组间主要结局指标（疼痛与功能）的差异。效应量通过标准化均数差（standardized mean differences, SMDs）结合95%置信区间（confidence intervals, CIs）进行计算。
结果
共计24项研究纳入描述性分析，18项研究纳入定量分析（荟萃分析，meta-analysis）。荟萃分析结果显示，与未接受治疗的患者相比，闭链运动干预可更显著地改善患者疼痛（SMD=−0.76；95%CI：−1.51, −0.01）与功能（SMD=−1.25；95%CI：−1.88, −0.62）。亚组荟萃分析显示，闭链运动联合常规物理治疗（conventional physical therapy, CPT）相较于单纯常规物理治疗，可更显著地改善患者疼痛（SMD=−1.18；95%CI：−1.70, −0.67）与功能（SMD=−1.27；95%CI：−1.79, −0.75）。偏倚风险评估结果显示，2项研究方法学质量为低质量，9项为中等质量，剩余13项为高质量。GRADE系统评价显示，闭链运动对膝骨关节炎患者疼痛与功能的干预证据等级均为低质量。
结论
尽管闭链运动在缓解膝骨关节炎患者疼痛、改善其功能方面展现出应用前景，但根据GRADE系统评价，相关证据质量仍为低等级。未来需开展更大样本量的高质量随机对照试验，以进一步验证闭链运动治疗膝骨关节炎的有效性。