Comparing Prophylactic Effect of Rivaroxaban and Enoxaparin on Thromboembolism After Total Hip or Knee Arthroplasty

Vascular thromboembolism is one of the major concerns of orthopedic surgeons after hip or knee replacement surgery. Although many thromboprophylactic drugs have been introduced, there is still no consensus over their efficacy and safety. Therefore, this study aimed to compare the efficacy and safety of oral rivaroxaban and aspirin administration and enoxaparin injections in patients undergoing knee or hip replacement.

Determination and comparison of the side effect and efficacy of Rivaroxaban and Enoxaparin after total hip or knee arthroplasty.

A total of 231 patients undergoing knee or hip replacement surgery were included in the study. Of them, 31 patients were excluded due to missing the follow-up. Of the remaining 200 patients, 42 low-risk and 158 moderate- to high-risk patients were identified, according to Caprini risk assessment model. Then, they were divided into three groups: aspirin (42 patients), enoxaparin (78 patients), and rivaroxaban (80 patients). Severe hemorrhage (hemoglobin reduction of more than 2 g/dL or requiring blood transfusion) was assessed after the first dose of medication until discharge through daily hemoglobin testing. Frequency of other side effects such as wound complications (ecchymosis, hematoma, and wound infection) and gastrointestinal or skin problems was recorded and compared by daily examination during the hospital stay and then in the future visits to the clinic up to 6 months in each group. Follow up visits were performed at weeks 6, 12, and 24.

No cases of deep vein thrombosis or pulmonary thromboembolism were observed in any of the study groups. There was no significant difference between the two groups in the number of major bleeding cases (P=0.39). Ecchymosis around the wound was significantly higher in the rivaroxaban group than in the enoxaparin group (33.8% vs. 23%). However, this difference was not statistically significant (P=0.06).

The efficacy and safety of rivaroxaban and enoxaparin drugs are comparable. Although ecchymosis was seen after using rivaroxaban rather than enoxaparin, rivaroxaban is orally administered and costs less for the patient and the health system. So, its use as a thromboprophylactic drug of choice following hip and knee arthroplasty surgery is still recommended.