Objective This study aimed to investigate how knee extensor and flexor strength change over time after anterior cruciate ligament reconstruction (ACLR). Design Systematic review with longitudinal meta-analysis. Data sources Medline, Embase, CINAHL, Scopus, Cochrane CENTRAL and SPORTDiscus to 28 February 2023. Eligibility criteria Studies of primary ACLR (n≥50), with mean participant age 18–40 years, reporting a quantitative measure of knee extensor or flexor strength were eligible. Muscle strength had to be reported for the ACL limb and compared with: (1) the contralateral limb (within-person); and/or (2) an uninjured control limb (between-person). Results We included 232 studies of 34 220 participants. Knee extensor and flexor strength showed sharp initial improvement postoperatively before tailing off at approximately 12–18 months post surgery with minimal change thereafter. Knee extensor strength was reduced by more than 10% compared with the contralateral limb and approximately 20% compared with uninjured controls at 1 year for slow concentric, fast concentric and isometric contractions. Knee flexor strength showed smaller deficits but was still 5%–7% lower than the contralateral limb at 1 year for slow concentric, fast concentric and isometric contractions. Between-person comparisons showed larger deficits than within-person comparisons. Conclusion Knee extensor muscle strength is meaningfully reduced (>10%) at 1 year, with limited improvement after this time up to and beyond 5 years post surgery. Many people likely experience persistent and potentially long-term strength deficits after ACLR. Comparison within person (to the contralateral limb) likely underestimates strength deficits in contrast to uninjured controls. Data are available in a public, open access repository. All data relevant to the study are included in the article or uploaded as supplementary information. Scripts and all data used are publicly available: [https://github.com/mgirdwood7/quadham\_acl\_sr][1]. [1]: https://github.com/mgirdwood7/quadham_acl_sr

中文翻译：

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ACL 重建后股四头肌和腘绳肌力量的故事：纵向和多变量荟萃分析的系统评价


目的 探讨前交叉韧带重建 （ACLR） 后膝伸肌和屈肌力量如何随时间变化。设计 系统评价和纵向荟萃分析。数据来源 Medline、Embase、CINAHL、Scopus、Cochrane CENTRAL 和 SPORTDiscus，截至 2023 年 2 月 28 日。资格标准 原发性 ACLR （n≥50） 的研究，平均参与者年龄为 18-40 岁，报告了膝伸肌或屈肌力量的定量测量。必须报告 ACL 肢体的肌肉力量，并与以下方面进行比较：（1） 对侧肢体（人内）;和/或 （2） 未受伤的控制肢体（人与人之间）。结果 我们纳入了 232 项研究，涉及 34 220 名参与者。膝伸肌和屈肌力量在术后最初表现出急剧改善，然后在术后约 12-18 个月逐渐减弱，此后变化很小。对于慢向心、快速向心和等长收缩，与 1 年相比，膝关节伸肌力量与对侧肢体相比降低 10% 以上，与未受伤对照组相比降低约 20%。膝屈肌力量显示出较小的缺陷，但在 1 年时，慢向心、快速向心和等长收缩仍比对侧肢体低 5%-7%。人与人之间的比较显示比人内比较的缺陷更大。结论 膝关节伸肌力量在 1 年时显著降低 （>10%），此后至术后 5 年及超过 5 年改善有限。许多人在 ACLR 后可能会出现持续且可能长期的力量不足。与未受伤的对照组相比，人内（与对侧肢体）的比较可能低估了力量不足。 数据在公共、开放访问存储库中可用。与研究相关的所有数据都包含在文章中或作为补充信息上传。脚本和所有使用的数据都是公开可用的：[https://github.com/mgirdwood7/quadham\_acl\_sr][1]。[1]：https://github。com/mgirdwood7/quadham_acl_sr