BackgroundLow-molecular-weight heparin (LMWH) and fondaparinux sodium (FPX) are routinely used to prevent deep vein thrombosis (DVT) after total knee arthroplasty (TKA). In this study, we compared the effects of these agents in preventing post-TKA DVT.MethodsClinical data of patients who underwent unilateral TKA for unicompartmental knee osteoarthritis at the Ningxia Medical University General Hospital between September 2021 and June 2022 were retrospectively analyzed. Based on the anticoagulation agent used, the patients were divided into LMWH and FPX groups (34 and 37 patients, respectively). Changes in perioperative coagulation-related indicators, d-dimer and platelet count, perioperative complete blood count, amount of blood loss, lower-limb DVT, pulmonary embolism, and allogeneic blood transfusion were determined.ResultsIntergroup differences in d-dimer or fibrinogen (FBG) levels before and 1 or 3 days after surgery were not significant (allp> 0.05); within-group pairwise comparisons indicated significant differences (all,p< 0.05). Intergroup differences in preoperative prothrombin time (PT), thrombin time, activated partial PT, and international normalized ratio were not significant (allp> 0.05), whereas significant differences were detected on postoperative days 1 and 3 (allp< 0.05). Intergroup differences in platelet counts before and 1 or 3 days after surgery were not significantly different (allp> 0.05). Pairwise comparisons of hemoglobin and hematocrit levels between patients in the same group before and 1 or 3 days after surgery revealed significant differences in both groups (allp< 0.05); however, intergroup differences were not significant (allp> 0.05). Although intergroup differences in visual analog scale (VAS) scores before and 1 or 3 days after surgery were not significant (p> 0.05), we detected significant intragroup differences in VAS scores before and 1 or 3 days after surgery (p< 0.05). The treatment cost ratio was significantly lower in the LMWH group than in the FPX group (p< 0.05).ConclusionBoth LMWH and FPX can effectively prevent DVT after TKA. There are some suggestive signals that FPX may have more beneficial pharmacological effects and clinical significance, while LMWH is cheaper and therefore more economical.