Objective

To evaluate effectiveness, in terms of patient-reported outcome measures, of platelet-rich plasma (PRP) injections for knee osteoarthritis compared to placebo and other intraarticular treatments.

Design

PubMed, Cochrane Library, Scopus, Embase, Web of Science, as well as the gray literature were searched on January 17, 2020. Randomized controlled trials (RCTs) comparing PRP injections with placebo or other injectable treatments, in any language, on humans, were included. Risk of bias was assessed following the Cochrane guidelines; quality of evidence was graded using the GRADE guidelines.

Results

Thirty-four RCTs, including 1403 knees in PRP groups and 1426 in control groups, were selected. WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) score favored PRP, with a statistically and clinically significant difference versus placebo at 12-month follow-up (P = 0.02) and versus HA (hyaluronic acid) at 6-month (P < 0.001) and 12-month (P < 0.001) follow-ups. A clinically significant difference favoring PRP versus steroids was documented for VAS (Visual Analogue Scale) pain (P < 0.001), KOOS (Knee Injury and Osteoarthritis Outcome Score) pain (P < 0.001), function in daily activities (P = 0.001), and quality of life (P < 0.001) at 6-month follow-up. However, superiority of PRP did not reach the minimal clinically important difference for all outcomes, and quality of evidence was low.

Conclusions

The effect of platelet concentrates goes beyond its mere placebo effect, and PRP injections provide better results than other injectable options. This benefit increases over time, being not significant at earlier follow-ups but becoming clinically significant after 6 to 12 months. However, although substantial, the improvement remains partial and supported by low level of evidence. This finding urges further research to confirm benefits and identify the best formulation and indications for PRP injections in knee OA.

中文翻译：

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PRP 注射治疗膝关节骨性关节炎：随机对照试验的荟萃分析。

客观的

为了评估与安慰剂和其他关节内治疗相比，富血小板血浆 (PRP) 注射治疗膝关节骨性关节炎的有效性，就患者报告的结果测量而言。

设计

于 2020 年 1 月 17 日对 PubMed、Cochrane Library、Scopus、Embase、Web of Science 以及灰色文献进行了检索。随机对照试验 (RCT) 比较了 PRP 注射与安慰剂或其他注射治疗，以任何语言，针对人类，被包括在内。根据 Cochrane 指南评估偏倚风险；使用 GRADE 指南对证据质量进行分级。

结果

选择了 34 项 RCT，包括 PRP 组 1403 例膝关节和对照组 1426 例膝关节。WOMAC（西安大略和麦克马斯特大学骨关节炎指数）评分有利于 PRP，在 12 个月的随访中与安慰剂相比（P = 0.02）和在 6 个月的随访中与 HA（透明质酸）相比具有统计学和临床​​显着差异（P < 0.001 ) 和 12 个月 ( P < 0.001) 的随访。在 VAS（视觉模拟量表）疼痛（P < 0.001）、KOOS（膝关节损伤和骨关节炎结果评分）疼痛（P < 0.001）、日常活动功能（P = 0.001）、和生活质量（P< 0.001) 在 6 个月的随访中。然而，PRP 的优势并未达到所有结局的最小临床重要差异，并且证据质量低。

结论

血小板浓缩物的作用超出了单纯的安慰剂作用，PRP 注射提供了比其他注射选择更好的结果。这种益处随着时间的推移而增加，在早期的随访中并不显着，但在 6 至 12 个月后变得具有临床意义。然而，虽然显着，但改善仍然是部分的，并得到低水平证据的支持。这一发现敦促进一步研究以确认益处并确定膝关节 OA 中 PRP 注射的最佳配方和适应症。