[Tranexamic Acid Reduces the Incidence of Heterotopic Ossifications after Elective Primary Total Hip Arthroplasty].

PURPOSE OF THE STUDY Heterotopic ossification is a frequent and a well-known complication after elective primary total hip arthroplasty. Prophylaxis is crucial since once the ossification is mature, the only treatment option is its surgical removal during revision hip surgery. There are pre-, peri- and postoperative prophylactic modalities. Ranking among the perioperative possibilities is the application of tranexamic acid in blood control management. The aim of our study is to prove the positive side effect of tranexamic acid application on reducing the heterotopic ossification ratio. MATERIAL AND METHODS A cohort of 401 total hip replacements was assessed retrospectively in the period from 2012 to 2016. Particular degrees were stratified based on the Brooker classification, sex, laterality and type of implant fixation. The average follow-up period is 6.10 years (range 40 m to 113 m). The hips treated in 2012 are taken as reference and the hips treated in 2016 are exposed to tranexamic acid protocol. Other secondary prophylactic modalities (pharmacological prophylaxis or radiotherapy), tertiary modalities (revision surgery) and trauma patients were excluded from the study. The acquired data were then statistically assessed. RESULTS Tranexamic acid protocol significantly reduces the incidence of heterotopic ossification after elective primary total hip replacement. In our cohort of 401 hips, the overall incidence of HO is 40.6%. The difference between the control group - 49.7% and the exposed group - 30.2% is statistically significant. More importantly, the clinically relevant types (III and IV) were also significantly reduced (12.7% vs. 4.2%). Other associated parameters such as uncemented implant, female sex and right-sided surgery further reduced the incidence of ossifications. DISCUSSION Identification of the risk patient, risk factors and subsequent care to maintain the range of motion, analgesia or potential removal of ossifications remain to be the priority in managing heterotopic ossifications after THA. Preoperative options to reduce the incidence of this complication are limited. Moreover, both the pharmacological prophylaxis and radiotherapy are associated with major complications and strict patient compliance is fundamental. Inclusion of simple tranexamic acid protocol in surgery management significantly reduces the risk of heterotopic ossification. CONCLUSIONS Development and maturation of heterotopic ossification is still intensively explored, but the main biochemical pathways are still unclear. Therefore, there is no causal treatment option nowadays. Individualisation of prophylactic treatment modalities leads to reduction in ossification development. It has been proven that one of these effective modalities is the tranexamic acid application before and after the procedure. This reduction is statistically significant and clinically relevant. Key words: tranexamic acid, total hip replacement, heterotopic ossification, prophylaxis, fixation type.