Comparative efficacy and safety of aspirin, low-molecular-weight heparin, and rivaroxaban for deep venous thrombosis prophylaxis after hip arthroplasty for femoral neck fracture: a single-center randomized controlled trial

OBJECTIVE: To evaluate the efficacy and safety of aspirin, low-molecular-weight heparin (LMWH), and rivaroxaban for deep vein thrombosis (DVT) prophylaxis after total hip arthroplasty (THA) or bipolar hemiarthroplasty (BHA) for femoral neck fracture, with subgroup analysis stratified by surgical type. METHODS: This single-center randomized controlled trial (RCT) was conducted between June 2024 and June 2025. A total of 217 consecutive patients with femoral neck fracture undergoing hip arthroplasty were initially screened, and 161 eligible patients were finally enrolled and randomly assigned to the aspirin group, LMWH group, or rivaroxaban group at a 1:1:1 ratio. All patients received standardized intermittent pneumatic compression (IPC) and graduated compression stockings for mechanical DVT prophylaxis, as well as a unified postoperative rehabilitation protocol. The primary outcome was the incidence of lower extremity DVT within 12 weeks postoperatively, confirmed by color Doppler ultrasound. The secondary outcome was the incidence of bleeding-related complications graded by the International Society on Thrombosis and Hemostasis (ISTH) criteria. All patients were followed up at 6, 8, and 12 weeks postoperatively, with routine bilateral lower extremity ultrasound performed at 12 weeks regardless of symptoms. Subgroup analysis was performed on the basis of surgical type (THA versus BHA). RESULTS: Among the 50 patients in the aspirin group, 5 (10.00%) developed DVT and 2 (4.00%) experienced bleeding complications. In the LMWH group (n = 58), 3 (5.17%) developed DVT and 3 (5.17%) had bleeding complications. In the rivaroxaban group (n = 53), 4 (7.55%) developed DVT and 12 (22.64%) had bleeding complications. No statistically significant difference in DVT incidence was observed among the three groups in either the overall cohort or THA/BHA subgroups (all P > 0.05). However, the incidence of bleeding complications in the rivaroxaban group was significantly higher than that in the aspirin and LMWH groups in both the overall cohort and surgical subgroups (all adjusted P < 0.0167). The baseline characteristics, surgical type distribution, operative duration, intraoperative complications, and postoperative ambulation time were well balanced among the three groups (all P > 0.05). CONCLUSIONS: Aspirin, LMWH, and rivaroxaban have comparable efficacy in reducing DVT incidence after both THA and BHA for femoral neck fracture. LMWH and aspirin exhibit more favorable safety profiles with significantly lower bleeding risk, while rivaroxaban is associated with a markedly higher incidence of bleeding complications and should be used with caution in elderly patients.