To compare the effects of intraarticular injection, intravenous drip and combined application of tranexamic acid (TXA) on blood loss and blood transfusion in patients undergoing total knee arthroplasty (TKA).

Through computer retrieval of English databases such as PubMed, Cochrane Library and Excerpta Medica Database(Embase) and Chinese databases such as China National Knowledge Infrastructure (CNKI), WanFang, VIP and Chinese BioMedical Literature Database (CBM), the relevant literature on the use of tranexamic acid in knee arthroplasty was searched. The literatures with randomized control methods were included, and the quality of the literatures was evaluated. The extracted data were analyzed by the software StataV.15.1.

A total of 40 randomized controlled trials were included, including 5 295 patients. The results of meta analysis showed that compared with intravenous drip of tranexamic acid, intra-articular injection had similar effects on total blood loss, drainage volume, postoperative hemoglobin level, hemoglobin reduction, blood transfusion rate and incidence of thrombotic events, there was no significant difference (P>0.05). Compared with single regimen, combined intravenous and local application of TXA could significantly reduce total blood loss[weighted mean difference (WMD)=-116.39, 95% confidence interval (CI) (-149.26, -83.52), P<0.05], reduce postoperative drainage [WMD=-57.99, 95%CI (-85.92, -30.06), P=0.005], increase postoperative hemoglobin level [standardized mean difference (SMD)=0.73, 95%CI (0.49, 0.98), P=0.001], decrease hemoglobin loss[SMD=-0.66, 95%CI(-1.06, -0.28), P=0.025] and blood transfusion rate[relative risk (RR)=0.43, 95%CI(0.30, 0.61), P<0.05]. There was no statistically significant difference in thrombus events between the two groups(P>0.05).

It is recommended to use tranexamic acid locally and intravenously in total knee arthroplasty, which can significantly improve the clinical outcome.