Regardless of the use of drainage, the two groups presented similar results in clinical outcomes such as functional score and complications at a mean follow up of 25 months. The most important finding of this study was disusing of drainage reduces loss of bleeding and minimizes the requirement of blood transfusions after BSTHA.
Unlike the current situation where the demand for BSTHA is increasing, there is little report about BSTHA without drainage. So this study was conducted with our expectation of the superiority of BSTHA without drainage. Blood loss was found to be less in the non-drainage group compared to that in the drainage group. In non-drainage group, this may be a consequence of the absence of blood loss into the drain and of none of the reduced effectiveness of topical TXA that was drained immediately with drainage. Many studies have described a positive correlation between non drainage and clinical outcomes after THA, which is consistent with the results of this study [13, 14].
Other strategies have been attempted to minimize blood loss recently. Among them, TXA is in the spotlight in reducing perioperative blood loss in total joint arthroplasty, recently [22]. Previous articles have demonstrated that a combined administration of TXA in THA is associated with a significantly reduced total blood loss and was safe for patients who received intravenous administration and topical application of TXA [23]. Steven BP et al. proved that it is safe to use in high risk patients with pro-thrombotic conditions. This study gives additional credence to the recent clinical guide on TXA administration in THA patients [24].
The higher the blood loss, the higher the incidence of blood transfusions. Blood transfusion requirements tended to be higher for patients in the drainage group. Kim et al. reported in a meta-analysis that allogenic blood transfusion is a significant risk factor for increasing the surgical site infection rate after total hip and knee joint arthroplasty [25]. However, in our study, we found no correlation between allogenic blood transfusion and surgical site infection. Also when drainage is not performed, blood may leak through the wound, which disrupts wound healing and may cause a surgical site infection. But in our study, there were no wound problem and significant infection cases. Furthermore, the non-drainage group generally showed higher satisfaction with easier movement during dressing of operation site and ambulation because of no drainage line. (Fig. 3).
Along with the positive aspects of without drainage, there were negative aspects as well. Higher morphine equivalent was derived in the patients without drainage, which means they felt more postoperative pain than the patients who underwent BSTHA with drainage. Rajesh and Prashant et al. proved that the presence of drainage significantly reduces opioid consumption during the first 6 hours after total knee arthroplasty [26]. Li S et al. randomly divided the patients undergoing high tibial osteotomy(HTO) into a drainage group and a no drainage group and the results showed that there was improvement of visual analogue scale (VAS) pain score in the non-drainage group until postoperative 5 days [27]. This is supported the fact that suction drainage can decrease immediate postoperative pain by draining hematoma production that results in increased pressure at the surgical site.
In this study, since TXA was used by same method in both groups, the effect could be excluded, but TXA also contributes to reducing postoperative pain. Tranexamic acid is a synthetic derivative of the amino acid lysine and binds the lysine binding sites on plasminogen, interfering with plasminogen binding to fibrin. By inactivating plasmin, TXA can prevent hyperfibrinolysis. Additionally, the coagulation-fibrinolysis process has been identified at interconnecting with inflammatory cascade [28]. Therefore TXA could play a exert an anti-inflammatory effect by inhibiting plasmin-mediated activation of complement, monocytes, and neutrophils recruitment to the implanted biomaterials, which may consequently minimize postoperative pain [29]. Administration of TXA also helps to reduce postoperative pain by reducing intra-articular hemarthrosis [30, 31]. But JW Wurtz et al. suggested an opposing opinion about role of TXA reducing postoperative pain. In this study, patients who received topical TXA reported higher mean 24-hour pain scores (P = 0.006) and requested opioid sooner (P = 0.033) compared to patients who did not receive TXA [32].
Several limitations existed in this study. Firstly, sample size is insufficient for a detailed and comprehensive analysis.
Secondly, this was a retrospective cohort study based on the database of a single institute. Thirdly, the mean follow-up period was not long enough to evaluate the long-term clinical outcomes. Fourthly, patients who undergo BSTHA usually have good physical conditions such as ASA grade 1 and 2; therefore, the result remain unknown in less healthier populations. Fifthly, if the satisfaction of patients and medical workers according to the presence of draining was investigated, it would have been a more meaningful study. Lastly, further studies are needed on the effect of TXA on postoperative pain.