Abstract: Objective To investigate the value of serum thrombomodulin (TM), P-selectin, and hemorheology indexes in predicting the risk of deep venous thrombosis (DVT) after surgery for femoral intertrochanteric fractures in the elderly. 
 Methods Clinical data of 98 elderly patients undergoing surgery for femoral intertrochanteric fracture were collected for retrospective study. The patients were divided into DVT group (n=30) and non-DVT group (n=68) according to whether postoperative DVT occurred. General data, TM, P-selectin and hemorheology indexes ［whole blood low shear viscosity (WBLSV), whole blood high shear viscosity (WBHSV), whole blood medium shear viscosity (WBMSV)］ of the two groups were recorded and compared. The value of TM, P-selectin and hemorheology indexes in predicting postoperative DVT was analyzed by receiver operating characteristic (ROC), and the risk factors of postoperative DVT were determined by multivariate Logistic regression analysis. 
 Results The levels of TM, P-selectin, WBLSV, WBHSV, and WBMSV in DVT group were higher than those in non-DVT group (P＜0.05). ROC analysis showed that TM, P-selectin,WBLSV, WBHSV, and WBMSV could all be used for predicting postoperative DVT in elderly patients with intertrochanteric fracture, and the areas under the ROC curve (AUC) were 0.906, 0.723, 0.674, 0.909, and 0.647, respectively (all P＜0.05). The results of multivariate Logistic regression analysis showed that TM ≥8.67 kU/L, P-selectin≥61.21 μg/L, WBLSV ≥9.035 mPa·s, WBHSV ≥4.725 mPa·s, WBMSV ≥5.665 mPa·s were risk factors for postoperative DVT in elderly patients with intertrochanteric fracture (P＜0.05). 
 Conclusion TM, P-selectin and hemorheology indexes can all be used to predict the risk of DVT in elderly patients with intertrochanteric fracture. Patients with high levels of TM, P-selectin,WBLSV, WBHSV, and WBMSV are more likely to develop DVT after surgery, suggesting that these indexes should be tested regularly and anticoagulation therapy should be given in time, to reduce the risk of postoperative DVT. 

Key words: femoral neck fractures, venous thrombosis, prediction