Patients in this project are randomly divided into three groups , one group is a blank group and the rest two groups receive either the topical or the intravenous form of tranexamic acid during unilateral THA(total hip arthroplasty).The total blood loss(TBL) will be calculated as the primary outcome for efficacy while the events of Deep Vein Thrombosis、Pulmonary Embolism、Acute Myocardial Infarction 、 Acute Kidney Infarction and Cerebral Infarction will be recorded to assess the safety of the tranexamic acid during a six-week follow-up for each patient.