Abstract: OBJECTIVE: At present, some randomized controlled clinical studies have proved that Buyang Huanwu Decoction can effectively prevent the occurrence of deep vein thrombosis in patients after orthopedic surgery, but it still lacks evidence-based medicine support. Here, we systematically evaluate the clinical efficacy and safety of Buyang Huanwu Decoction in the prevention of deep venous thrombosis after orthopedic surgery.
METHODS: By March 2020, literatures regarding clinical randomized controlled trials on the prevention of deep vein thrombosis after orthopedic surgery by Buyang Huanwu Decoction were retrieved from PubMed, Embase, Cochrane Library, CNKI, VIP, WanFang and China Biological Literature Database. The experimental subjects were patients after orthopedic surgery. In trial group, Buyang Huanwu Decoction was given for prevention of postoperative deep vein thrombosis in patients, and in control group, routine western medicine given for prevention. The quality of the retrieved original literature was evaluated according to the evaluation criteria of Cochrane Handbook 5.1.0 and Modified Jadad scale. Meta-analysis was performed using RevMan 5.3 and Stata 16, and TSA 0.9.5.10 Beta software was used for trial sequential analysis. Postoperative incidence of deep vein thrombosis, prothrombin time, activated partial thromboplastin time, fibrinogen, D-dimer, postoperative drainage volume and incidence of adverse reactions were compared between the two groups.
RESULTS: The Jadad scores of all the included articles were 4 points or below, and the overall quality of the literatures was not high. Sixteen articles involving 1 075 patients were enrolled, including 540 in the trial group and 535 in the control group. The results of meta-analysis showed that: The incidence of deep vein thrombosis in the trial group [relative risk (RR)=0.54, 95% confidence interval (CI): 0.41-0.71, P < 0.000 1], D-dimer [weighted mean difference (WMD)=-0.13, 95%CI: -0.22 to-0.04, P=0.003] and postoperative drainage (WMD=-80.39, 95%CI: -102.14 to -58.64, P < 0.000 01) were all significantly lower than those in the control group, and the level of prolonged prothrombin time was lower than that in the control group (WMD=-0.59, 95%CI:  -1.07 to -0.01, P=0.02). There was no significant difference in the activated partial thromboplastin time (WMD=0.23, 95%CI: -1.72 to 2.17, P=0.82) and fibrinogen (WMD=-0.27, 95%CI: -0.63 to 0.09, P=0.15) between the two groups. The incidence of adverse reactions in the trial group was significantly lower than that in the control group (RR=0.31, 95%CI: 0.14-0.68, P=0.004). Sequential analysis of the trial showed that the cumulative incidence of deep vein thrombosis crossed the traditional boundary value and the boundary value of trial sequential analysis, which further confirmed the clinical efficacy of Buyang Huanwu Decoction. 
CONCLUSION: Buyang Huanwu Decoction can effectively reduce the incidence of deep vein thrombosis in patients after orthopedic surgery, and has a certain degree of safety. However, more high-quality randomized controlled trials need to be included for further verification.

Key words: bone, traditional Chinese medicine, Buyang Huanwu Decoction, orthopedics, deep venous thrombosis, prevention, randomized controlled clinical studies, meta-analysis