Efficacy of Repair for ACL Injury: A Meta‑analysis of Randomized Controlled Trials

Abstract

We aim to compare the curative effect of primary repair for anterior cruciate ligament (ACL) injury with reconstruction and provide the reliable evidence for its clinical application. The literatures were searched in PubMed, EMBASE, Springer, and other medical literature databases published between January 1970 and June 2021. Basic characteristics, surgery technique, clinical outcome scores and physical examination results were recorded and evaluated. Seven randomized controlled trials (RCT) were eligible for inclusion. The results showed that there were no statistically significant differences between arthroscopic ACL repair and ACL reconstruction for Tegner, Lysholm, Lachman, KT-1000, range of motion (ROM), functional outcomes and reoperation rate (P>0.05), even the result of IKDC scores showed that arthroscopic repair was better than reconstruction (P=0.04). However, through the subgroup analysis, it was found that the short-term follow-up results of arthroscopic ACL repair were indeed better than those of open ACL repair. Therefore, we can assume that the arthroscopic ACL repair technique is an optional and promising surgical method to treat ACL injury.

Fig. 1

Search strategy flow diagram.

Fig. 2

a Risk of bias graph exhibiting the review of the authors’ judgments about each risk of bias item presented as percentages across all included studies. b Risk of bias summary revealing the review of the authors’ judgments about each risk of bias item for included RCTs. Minus sign represents the risk of bias present, plus sign indicates the risk of bias absent, and question mark equals the risk of bias uncertain. c The funnel plots of the included studies. RR, relative risks; SE, standard error.

Fig. 3

a Difference in the Tegner score and the subgroup analysis; b Difference in the Lysholm score and the subgroup analysis. CI, confidence interval; IV, inverse variance; SD, standard deviation. The solid squares indicate the mean difference and are proportional to the weights used in the meta-analysis. The solid vertical line indicates no effect. The horizontal lines represent the 95% CI. The diamond indicates the weighted mean difference, and the lateral tips of the diamond indicate the associated 95% CI.

Fig. 4

a Difference in the IKDC score; b Difference in the incidence of KT-1000 (≥3 mm). CI, confidence interval; IV, inverse variance; M-H, Mantel-Haenszel. The solid squares indicate the mean difference and are proportional to the weights used in the meta-analysis. The solid vertical line indicates no effect. The horizontal lines represent the 95% CI. The diamond indicates the weighted mean difference, and the lateral tips of the diamond indicate the associated 95% CI.

Fig. 5

Difference in the incidence of Lachman test (2+/3+) and the subgroup analysis; CI, confidence interval; IV, inverse variance; M-H, Mantel-Haenszel. The solid squares indicate the mean difference and are proportional to the weights used in the meta-analysis. The solid vertical line indicates no effect. The horizontal lines represent the 95% CI. The diamond indicates the weighted mean difference, and the lateral tips of the diamond indicate the associated 95% CI.

Fig. 6

a Difference in the incidence of flexion limitation (≥10°); b Difference in the incidence of extension limitation (≥5°). CI, confidence interval; IV, inverse variance; M-H, Mantel-Haenszel. The solid squares indicate the mean difference and are proportional to the weights used in the meta-analysis. The solid vertical line indicates no effect. The horizontal lines represent the 95% CI. The diamond indicates the weighted mean difference, and the lateral tips of the diamond indicate the associated 95% CI.

Fig. 7

Difference in the functional outcomes of muscle strength and the subgroup analysis. CI, confidence interval; IV, inverse variance; SD, standard deviation. The solid squares indicate the mean difference and are proportional to the weights used in the meta-analysis. The solid vertical line indicates no effect. The horizontal lines represent the 95% CI. The diamond indicates the weighted mean difference, and the lateral tips of the diamond indicate the associated 95% CI.

Fig. 8

Difference in the incidence of reoperation and the subgroup analysis. CI, confidence interval; M-H, Mantel-Haenszel. The solid squares indicate the mean difference and are proportional to the weights used in the meta-analysis. The solid vertical line indicates no effect. The horizontal lines represent the 95% CI. The diamond indicates the weighted mean difference, and the lateral tips of the diamond indicate the associated 95% CI.

Fig. 9

Difference in the continuous variable results for ACL repair and the subgroup analysis. CI, confidence interval; IV, inverse variance; SD, standard deviation; The solid squares indicate the mean difference and are proportional to the weights used in the meta-analysis. The solid vertical line indicates no effect. The horizontal lines represent the 95% CI. The diamond indicates the weighted mean difference, and the lateral tips of the diamond indicate the associated 95% CI.

Fig. 10

Difference in the categorical variable results for ACL repair and the subgroup analysis. CI, confidence interval; M-H, Mantel-Haenszel. The solid squares indicate the mean difference and are proportional to the weights used in the meta-analysis. The solid vertical line indicates no effect. The horizontal lines represent the 95% CI. The diamond indicates the weighted mean difference, and the lateral tips of the diamond indicate the associated 95% CI.