Zhang W, et al. - In this retrospective cohort study, researchers investigated the risk factors (such as preoperative time, fracture sites, chronic diseases {hypertension, diabetes and coronary disease} and D-dimer levels) for perioperative deep vein thrombosis (DVT), a serious complication of the major orthopaedic surgery, after orthopaedic surgery in patients with traumatic fracture and their potential clinical diagnostic values. From May 1, 2016, to February 31, 2017, this investigation was conducted with surgically treated fracture patients in Honghui Hospital. The examination of the correlation between perioperative DVT and the factors of preoperative time, fracture sites, D-dimer value and chronic diseases was conducted using χ² test, independent sample t test and regression analysis. An analysis of 462 patients has been registered. Investigators found that patients with DVT had significantly longer preoperative time than patients with non-DVT. Preoperative D-dimer's sensitivity and specificity for DVT diagnosis was 71.30% and 44.83%, 63.90% and 70.51% for postoperative D-dimer. Findings revealed that the incidence of DVT was correlated with the fracture site. In patients with lower extremity traumatic fractures, prolonged preoperative time and increased D-dimer value were independent risk factors for DVT.