The identification of risk factors for deep venous thrombosis (DVT) following orthopedic surgery remains unclear. We have investigated the relationship between plasma levels of D-dimer (DD), the presence or absence of microemboli 1 day after surgery, and the occurrence of DVT 7 days after total hip or knee replacement. The prevalence of DVT was 25 (13.3%) among 188 patients and was lower in 112 patients with DD < 2808 ng mL(-1) than in the 56 patients with higher DD levels: respectively, 8.0% vs. 21.4% (p < 0.05). D-dimer is not suitable for individual estimation of DVT risk. Microemboli were found in 112 (60%) of 186 subjects. The presence/absence or the frequency of the microemboli showed no relationship with the occurrence of DVT. Last, when evaluating the risk of DVT in orthopedic surgery, microemboli detection does not add to the interpretation of DD concentration.